STEMscopes Georgia Science Student Notebook Grade 6 by acceleratelearning

6 STEMscopes Georgia Student Notebook

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6th grade Notebook

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developed by Accelerate Learning, Inc. & Rice University

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GEORGIA Student Notebook – Sixth Grade ISBN: 978-1-946725-76-9

Published by Accelerate Learning Inc., 5177 Richmond Ave, Suite 800, Houston, TX 77056. Copyright © 2017, by Accelerate Learning Inc. All rights reserved. No part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without prior written consent of Accelerate Learning Inc., including, but not limited to, in any network or other electronic storage or transmission, or broadcast for distance learning. To learn more, visit us at www.acceleratelearning.com

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GEORGIA

This Student Notebook is designed to be used as a companion piece to our online curriculum. The pages of this book are organized and follow the 5E model.

Student Handout

ENGAGE

A short activity to grab students’ interest

Student Journal

EXPLORE

A hands-on activity in which students get expereince with the concept being taught

STEMscopedia

EXPLAIN

A reference material that includes parent connections, technology, and science news

Reading Science A reading passage about the concept that includes comprehension questions

ELABORATE Math Connection

A set of grade-level appropriate math problems that address the concept

Writing Science

EVALUATE

A writing prompt based on the concept studied in which the students can demonstrate what they have learned

Only student pages are included in this book and directions on how to use these pages are found in our online curriculum. Use the URL address and password provided to you by your district to access our full curriculum.

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Sixth Grade Student Notebook Table of Contents

Lesson

Page

Earth and Space Science 6E1AB

6E1CE

6E1D

6E2ABC

6E3AC

109

6E3B

131

6E3D

149

6E4A

167

Models of the Universe and Solar System

Comparing Objects in the Solar System

Motion in the Solar System

Positions of Earth, Moon, and Sun

Water on Earth

The Water Cycle

Waves, Currents, and Tides

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iii

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Sixth Grade Student Notebook Table of Contents

Lesson

Page

Earth and Space Science 6E4B

185

6E4C

213

6E4D

233

6E4E

257

6E5A

277

6E5B

295

6E5C

319

6E5DE

345

Sun’s Energy on Earth

Heat’s Effect on Wind Systems

Meteorlogical Events

Moisture and Weather Patterns

Layers of Earth

Minerals and Rock Composition

Classifying Rocks

Weathering, Erosion, and Deposition

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Sixth Grade Student Notebook Table of Contents

Lesson

Page Earth and Space Science

6E5F

375

6E5G

399

6E5H

417

6E6A

437

6E6B

459

6E6C

473

Plate Tectonics

Fossil Evidence of a Changing Earth

Soil Composition

Renewable and Nonrenewable Resources

Sustaining Natural Resources

Rising Global Temperatures

Appendix Glossary

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6th Grade Earth and Space Science

6E1AB

Models of the Universe and Solar System

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6E1AB Models of the Universe and Solar System

Student Handout

Name:

Date:

Not an Explosion 1.

Draw the rubber band (with paper clips) before you stretched it. Then draw it as it appeared while stretched out. Before Stretching

After Stretching

Explain how the paper clips moved in relation to one another.

Did the paper clips change in size?

If this model represents the universe, what does the rubber band represent? What do the paper clips represent?

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6E1AB Models of the Universe and Solar System

Student Journal Name:

Date:

Group:

Part I: Your Research and Presentation In this section, record your research. Research Topic and Question Who are the scientists involved in this work? What did they discover?

When did they discover this?

Where was the discovery made?

Why is the discovery important? How was it discovered? What scientific instruments were used? What are some interesting facts about the discovery?

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6E1AB Models of the Universe and Solar System

Student Journal Use this page to help you plan your presentation. Notify your teacher if you need any supplies. 1. What will you use for your presentation?

2. Supplies needed:

3. Who will present each section?

4. Other notes:

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6E1AB Models of the Universe and Solar System

Student Journal Part II: Student Presentation Data Collection When presentations are ready, participate in your group’s presentation. Watch and listen to the other presentations. Fill in the data tables below as the information is revealed. Question 1: Galaxy Imagery Who? What? When? Where? Why? How? Instruments? Facts Question 2: Star Formation Who? What? When? Where? Why? How? Instruments? Facts Question 3: Formation of Celestial Objects Who? What? When? Where? Why? How? Instruments? Facts © Accelerate Learning Inc. - All Rights Reserved

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6E1AB Models of the Universe and Solar System

Student Journal Part II: Student Presentation Data Collection, continued Question 4: Expansion Rate and the Redshift Who? What? When? Where? Why? How? Instruments? Facts Question 5: Telescopes Who? What? When? Where? Why? How? Instruments? Facts Question 6: Cosmic Background Radiation Who? What? When? Where? Why? How? Instruments? Facts

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6E1AB Models of the Universe and Solar System

Student Journal Part II: Student Presentation Data Collection, continued Question 7: Big Bang Model Who? What? When? Where? Why? How? Instruments? Facts Question 8: Properties of Galaxies Who? What? When? Where? Why? How? Instruments? Facts

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6E1AB Models of the Universe and Solar System

Student Journal Part III: Model It! Directions: Based on your research and the presentations from your classmates, draw a model of the Milky Way galaxy in the space below, including a zoomed-out diagram of the solar system. Criteria: 1. The Milky Way should include the basic shape. Label the section where the solar system is located. 2.

The solar system should include the Sun and planets. It does not have to be drawn to scale. However, the planets should be labeled.

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6E1AB Models of the Universe and Solar System

Student Journal Reflections and Conclusions 1.

Name some ways data is collected by astronomers.

Name some of the important astronomers.

What is the cosmic background radiation? What did we learn from this discovery?

What does redshift mean? What did we learn about the universe with this discovery?

Explain what you know about the big bang model.

Explain how astronomers have determined the location of the solar system in the Milky Way galaxy.

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STEMscopedia: MODELS OF THE UNIVERSE AND SOLAR SYSTEM

6E1AB

Reflect When you look up at the stars at night, do you think people have always understood our place in space? Sometimes we take for granted what we have learned from modern technology. To ancient Greek observers, celestial objects seem to move across the sky as though they were orbiting Earth. Telescopes had not yet been invented, so only five planets were known to them: Mercury, Venus, Mars, Jupiter, and Saturn. Stars seemed to be just beyond the clouds.

Ptolemy’s Geocentric Model (circa 100–200 AD)

Geocentric Model of the Universe The geocentric (Earth-centered) model of the universe persisted for centuries based on the false assumption that Earth stood still and was the center of the universe. The geocentric model was promoted by Ptolemy (about 100–200 AD), a Greek philosopher who studied in Egypt. He believed that Earth did not move and was at the center of the universe. He also thought other celestial bodies moved in perfect circles. To him, stars were set in a rotating sphere that turned east to west once a day; and the planets, Moon, and Sun were also set in separate spheres that moved slower. He thought planets moved in circles (called epicycles) around Earth.

Heliocentric Model of the Universe Promoted by Nicholas Copernicus, the heliocentric model revolutionized scientific thinking in the 16th century and replaced the geometric model. Heliocentric comes from the Greek word “helios,” meaning “Sun.” In this model, Earth and the other five known planets (Mercury, Venus, Mars, Jupiter, and Saturn) orbited the Sun.

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Copernicus’ Heliocentric Model (1543)

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STEMscopedia: MODELS OF THE UNIVERSE AND SOLAR SYSTEM

The Solar System Today Telescope observations revealed the seventh planet Uranus in 1781 and the eighth planet Neptune in 1846. Although Pluto, discovered in 1930, held the honor as the ninth major planet, it was reclassified as a dwarf planet in 2006. The Big Bang Theory The universe includes everything that exists: all matter, energy, space, and time. But how did the universe come into existence? It may be difficult to imagine the origins of the universe. Where did the universe and its components come from? Scientists have found solid evidence that the universe had a beginning. The big bang theory is the most widely accepted theory to explain the origin of the universe. According to this theory, the universe began as a single, tiny point—smaller than an atom—called a singularity. This singularity was infinitely hot and infinitely dense—it contained all the matter and energy currently in the universe. The big bang was the moment when all of this matter and energy suddenly expanded out from this singularity. The universe has been expanding ever since the laws of physics, including gravity, came into effect during the big bang. In the first seconds after the big bang, gravity caused matter to come together to form the particles from which all components in the universe are made: protons, neutrons, and electrons. During these seconds, the universe was too hot for these particles to form atoms. Also, the clouds of subatomic particles—these protons, neutrons, and electrons— were so dense that no light could shine through them. About three seconds after the big bang, the universe had cooled enough for protons and neutrons to come together to form simple nuclei.

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STEMscopedia: MODELS OF THE UNIVERSE AND SOLAR SYSTEM

After about 300,000 years, electrons joined with these nuclei to form atoms of the simplest elements. Hydrogen, which contains only one proton per atom, was the ﬁrst element to form. Helium, which contains two protons per atom, formed next. To this day, hydrogen and helium remain the most common elements in the universe. As atoms continued to form, the dense cloud of subatomic particles began to clear. For the ﬁrst time, light could shine through the universe.

Look Out Prior to the discovery of the big bang, many scientists thought the universe had always existed— and would always exist—in an unchanging state. This was called the steady state theory. The steady state theory was disproved in the 1920s by a scientist named Edwin Hubble. By analyzing light from distant stars, Hubble discovered the universe is actually expanding. This discovery led to the Big Bang theory. Scientists reasoned that if the universe is expanding, it must once have been compressed into a much smaller, denser space. Later discoveries have continued to support the big bang theory.

What Do You Think Since the beginning of the universe cannot be observed, how can scientists study the big bang? How can they know when the big bang happened? Take a moment to answer these questions for yourself, and then read on to learn! The Expanding Universe and Redshift The fact that the universe is expanding was one of the most important early pieces of evidence for the big bang theory. To understand how scientists know the universe is expanding, you need to know a bit about light waves. When stars give off light, the light travels in waves through space. Some waves are longer; we see longer waves as red light. Some waves are shorter; we see shorter waves as blue light. As a star moves away from Earth, light waves from the star that reach Earth seem to have stretched. As a result, the star appears redder. This is called redshift. In contrast, as a star moves toward Earth, light waves from the star that reach Earth seem to compress. As a result, the star appears bluer. This is called blueshift.

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STEMscopedia: MODELS OF THE UNIVERSE AND SOLAR SYSTEM

The stars and galaxies that Edwin Hubble observed experienced redshift. In other words, they were moving away from Earth. If galaxies are moving away from Earth (and each other), the universe cannot exist in a steady state. Hubble ultimately concluded the universe must be expanding. He also discovered that galaxies farther from Earth experience greater redshift. In other words, the farther a galaxy is from Earth, the faster it is moving away from Earth. Not only is the universe expanding, Hubble concluded that it must be expanding more quickly all the time! Scientists can now measure the intensity of a galaxy’s redshift and use this value to calculate the galaxy’s distance from Earth and the speed at which it is moving. Scientists still have not developed a way to measure the current size of the universe. The Age of the Universe Visible light is a form of electromagnetic radiation: energy that travels through space in wave-like patterns at high speeds. In fact, this energy is the fastest thing in the universe. Electromagnetic radiation travels at a constant rate of about 300,000 kilometers per second. (We call this the speed of light.) Because the universe is so vast and light moves so quickly, light gives scientists a useful tool for measuring distances in space. As you will see, scientists can also use light to measure the universe’s age. A light-year is the distance light travels in one year, which is about 9.5 trillion km. If a star is four light-years from Earth, light from that star takes four years to reach Earth. If a star is four million light-years from Earth, light from that star takes four million years to reach Earth. This means scientists are looking into the past when they observe electromagnetic radiation in space. Scientists can estimate the age of the universe by observing the universe’s oldest stars and the intensity of their redshift. Scientists can use these observations to calculate the rate of the expansion of the universe and work backward to determine when the expansion began. Using this method, scientists have estimated that the universe is about 13.7 billion years old. In other words, the big bang occurred 13.7 billion years ago.

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STEMscopedia: MODELS OF THE UNIVERSE AND SOLAR SYSTEM

Getting Technical: Remote Sensing Instruments Much of what we know about the nature and origin of the universe comes from the study of visible light through light-sensing telescopes. However, all objects in the universe emit forms of electromagnetic radiation other than visible light. Scientists can use remote sensing instruments—special telescopes and other tools—to detect these invisible forms of electromagnetic radiation and study the objects that emit them. Remote sensing instruments are essential for studying the far reaches of the universe. Many objects are too distant or dim to detect with visible light. They Scientists give off low-energy forms of electromagnetic radiation, such as radio waves, can use radio microwaves, and infrared radiation. Scientists can use large radio telescopes, telescopes similar in appearance to large satellite dishes, to detect radio waves from like this one space. These radio telescopes are located on Earth’s surface, but they allow to observe us to study distant stars that would otherwise be invisible. distant Other remote sensing instruments are launched into space. This objects in the allows scientists to observe the objects in the universe without interference universe. from man-made lights on Earth’s surface or particles in Earth’s atmosphere. One such instrument is the Wilkinson Microwave Anisotropy Probe (WMAP). WMAP is a satellite launched in 2001 to examine cosmic microwave background (CMB) radiation, which is electromagnetic radiation left over from the initial stages of the big bang. The massive explosion that started the big bang gave off a tremendous amount of energy. With the help of WMAP, scientists have been able to observe this leftover radiation throughout the universe. Having a clear picture of CMB radiation allows scientists to map out matter in the universe. CMB radiation also provides evidence for the big bang theory. Nearly all of the CMB radiation is the same temperature; this indicates the radiation was released at the same time. Some small temperature variations do exist, however, indicating different amounts of matter in different parts of the universe. Areas where the CMB radiation indicates more matter was created in the early universe correspond to areas with large clusters of galaxies in the modern universe. The WMAP is used to detect CMB radiation.

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STEMscopedia: MODELS OF THE UNIVERSE AND SOLAR SYSTEM

Where are we in space? By the 20th century, telescope observations by Edwin Hubble revealed that our solar system is in the Milky Way galaxy, but it was one of billions of galaxies in an expanding universe, grouped into clusters and superclusters. By the end of the 20th century, the structure of the visible universe emerged with superclusters forming into a vast web of filaments and voids.

What Do You Know? The following image was created by WMAP. It is an image of the CMB radiation left over from the big bang. The different colors represent differences in temperature that correspond to different densities of matter. Red and yellow areas are hotter, and dark blue areas are cooler. Take a few moments to study this image. Circle the areas in the image that you think indicate areas containing more matter. Box the areas in the image that you think indicate areas containing less matter. Notice that most of the image is the same color, meaning most of the CMB radiation is the same temperature. Write a paragraph explaining in your own words how this observation provides evidence to support the big bang theory.

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STEMscopedia: MODELS OF THE UNIVERSE AND SOLAR SYSTEM

Connecting With Your Child Visualizing the Big Bang To help your child visualize the big bang, try doing a simple demonstration together. Go outside and gather a handful of soil and clump it into a tight ball. Let your child feel the density of the soil when it is compressed. Then have your child throw the ball of soil down onto the sidewalk. You can put down a white piece of paper ﬁrst if a sidewalk is not available or will not provide enough visual contrast. Take a look at the soil together. Discuss how all of the soil expanded from a single point upon impact, and take a look at where the soil ended up after this “explosion.” Some of the soil will still be in a large clump in the middle, while some will have spread out at some distance. This can represent how matter expands at different speeds throughout the universe. The soil that is farther from the point of impact traveled more quickly than the soil that stayed in the middle. However, everything can still be traced back to that central point. This is similar to the way all matter in the universe expanded from a single point. The matter that is farther away is moving faster, but it can still be traced back to the original singularity. This is a simpliﬁed demonstration, but it may help your child visualize the expansion of the universe. Here are some questions to discuss with your child: 1. How does the density of the soil change from its original state compared to its current state after the expansion? 2.

Why is some of the soil farther away than the rest of it?

How does this demonstration relate to what you have learned about the big bang theory and the expansion of the universe?

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6E1AB Models of the Universe and Solar System

Reading Science Name:

Date:

Group:

Origins of the Universe 1

Have you ever wondered how the universe began? Where did all the planets and stars and other objects in space come from? What else could be out there? Scientists have been trying to answer these and other questions like them since the beginning of mankind. No one knows the answers for sure, but many theories and myths have been created to help explain the answers to these questions.

The most popular theory for the creation of the universe is known as the Big Bang. The Big Bang theory suggests that everything in the universe was once condensed into an incredibly small area. Because this area was extremely hot, a powerful expansion of energy was created. It sent everything that was densely packed in the small area flying out in all directions. In the blink of an eye, this microscopic area expanded into something larger than the Milky Way galaxy. Within seconds, everything began to cool down. Still expanding, the building blocks of the universe began to form. As millions of years went by, the universe’s temperature cooled enough to allow galaxies and stars to form. To this very day, the universe is still cooling and expanding.

The Big Bang theory is not the only theory that tries to explain the creation of the universe, but it is currently the most popular because of the amount of evidence that supports it. Scientists have discovered that galaxies are traveling away from Earth. Scientists know this by studying the color of light that the galaxies give off. If light from a galaxy appears to be shifted toward the red end of the electromagnetic spectrum, then this means it is traveling away from Earth. This supports the idea of a great expansion from the Big Bang.

Another piece of evidence that supports the Big Bang was found in 1992 by the Cosmic Background Explorer satellite. It precisely measured the temperature of the cosmic microwave background radiation. The temperature it found matched the predictions astronomers had made of the hot Big Bang. This radiation is believed to be caused by the energy released during the first year of the Big Bang.

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6E1AB Models of the Universe and Solar System

Reading Science Continued 5

Scientists have estimated that the universe was formed over 13 billion years ago. In 1995, scientists pointed the Hubble Space Telescope into an area of space that appeared to be empty. Over a period of 240 hours, the images that were sent back to Earth were breathtaking. Thousands upon thousands of galaxies appeared in a space as small as a grain of sand. Scientists predict that if the entire sky has this many galaxies in each little empty space, there could be over 50 billion galaxies in the universe. The farthest of these galaxies is over 13 billion light years away. This supports the Big Bang theory by telling scientists how old our universe is.

The universe’s creation is still a mystery to scientists. The Big Bang is just one theory that tries to explain the origins of the universe. Exactly how big the universe is, or where it is expanding to, continues to fascinate scientists and nonscientists alike.

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6E1AB Models of the Universe and Solar System

Reading Science 1.

What is one piece of evidence that supports the Big Bang theory? A

The rotation and revolution of Earth.

The universe formed over 13 billion years ago.

The universe is cooling down.

A weak signal of cosmic microwave background radiation.

Which of the following is the main idea in paragraph 2? A

History of the Hubble Space Telescope.

Background on the Cosmic Background Explorer satellite.

Explanation of the Big Bang theory.

Discussion of evidence that supports theories.

What does it mean if a galaxy gives off light that has been shifted toward the red end of the electromagnetic spectrum? A

The galaxy is much older than Earth.

The galaxy is moving away from Earth.

The galaxy is very hot and has not cooled down yet.

The remnants of an explosion are between the galaxy and Earth.

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6E1AB Models of the Universe and Solar System

Reading Science 4.

What is the best description of the Big Bang? A

A massive explosion that created everything in the universe

Two planets collided creating the Sun and other planets

A rapid expansion of a small, densely packed area that expanded into the universe that we know today

An explanation of how the universe is expanding and how big it is

What is the main purpose of the passage? A

To point out that good scientific evidence supports the Big Bang theory

To prove that the Big Bang never happened

To explain why scientists continue to search for evidence of the Big Bang

To describe that there are fewer galaxies than scientists had first suspected

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6E1AB Models of the Universe and Solar System

Math Connections Name:

Date:

Group:

According to the Big-Bang Theory, matter did not exist before the Big Bang occurred. Scientists believe the universe began with the Big Bang about 14 billion years ago. Before the Big Bang, space and time were set to zero. After the Big Bang, the four basic forces—gravity, electromagnetic force, strong nuclear force, weak nuclear force—began to function, and the universe started to expand rapidly. 1.

After the Big Bang, scientists believe the Earth cooled 3,000 degrees in the first 300,000 years. Write a ratio comparing those two quantities, and find the unit rate for how many years it took to cool 1 degree. Many galaxies are in space, some larger and some smaller than the Milky Way galaxy we live in. The chart below compares the diameters of several galaxies in light-years. Galaxy Name

Diameter in Light-Years

Type

Milky Way

100,000

Spiral

NGC-1569

8,000

Irregular

NGC-908

75,000

Irregular

Hoag’s Object

120,000

Elliptical

M-33

50,000

Spiral

Hercules A

1,500,000

Elliptical

M-31-Andromeda

220,000

Spiral

NG-4449

20,000

Irregular

Write a ratio to compare the spiral galaxy M-33 to the irregular galaxy NGC-908. How many times larger is the NGC-908 galaxy than the M-33 galaxy?

Compare the elliptical galaxy Hoag’s Object to the irregular galaxy NGC-1569 using a ratio. How do they compare?

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6E1AB Models of the Universe and Solar System

Math Connections 4.

The ratio of the diameter of the spiral galaxy Andromeda to the diameter of another unknown galaxy is 11:1. Use the chart above to help you figure out the unknown galaxy.

The Hercules-A elliptical galaxy is 15 times larger than the Milky Way galaxy. How much larger than NGC-1569 is the Milky Way?

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6E1AB Models of the Universe and Solar System

Writing Science Name:

Date:

Group:

LOOK

THINK Think about the scientific theories that describe the origin of the universe. WRITE Explain how scientific data can be used in developing scientific theories to describe the origin of the universe. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E1AB Models of the Universe and Solar System

Writing Science

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6th Grade Earth and Space Science

6E1CE

Comparing Objects in the Solar System

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6E1CE Comparing Objects in the Solar System

Student Handout

Name:

Date:

The Solar System

Work with your group to decide which ball in the image above would best represent the size of Jupiter if Earth were the size of a ping-pong ball. Explain your reasoning.

Now that your class has chosen which ball best represents Jupiter, form a circle with your group to represent the size of the Sun at the same scale. Explain your reasoning.

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6E1CE Comparing Objects in the Solar System

Student Journal Name:

Date:

Group:

Background Questions 1.

What was invented in the 17th century? How did this help the study of our universe?

What is a probe?

Describe the Galileo probe mission.

What are scientists who study space called?

Why is Pluto no longer considered a planet? Who determined this?

Why does our knowledge of space increase with new technology?

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6E1CE Comparing Objects in the Solar System

Student Journal Part I: Space Research Groups

Use the resources provided to learn about your group of celestial objects. Then teach your solar system team about your objects.

The Inner Planets Mercury

Venus

Earth

Size Compared to Earth

smaller

Distance From the Sun (km) Surface Features

150 million

It has a rocky surface that is covered in craters and ancient lava fields.

Atmospheric Features

Thick sulfuric clouds surround Venus. Below these clouds, the temperature is extremely high, making Venus the hottest planet.

Ability to Support Life

Interesting Fact

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Mars

Conditions are present for life (distance from the Sun, availability of water, appropriate temperature ranges). It has no moon.

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6E1CE Comparing Objects in the Solar System

Student Journal Part I: Space Research Groups, continued

Use the resources provided to learn about your group of celestial objects. Then teach your solar system team about your objects.

The Outer Planets Jupiter Size Compared to Earth

Saturn

Uranus

It is larger than Earth. (It is the largest planet in our solar system, as wide as 11 Earths lined up side by side.)

Distance From the Sun (km)

4.5 billion

Surface Features

It is a gas giant. The thick atmosphere ends at a liquid layer and there is no rocky surface.

Atmospheric Features

Ability to Support Life

Planet appears blue due to the top layer of the atmosphere being mainly methane. Below that, the atmosphere is similar to the other gas giants. It is unable to support life due to incredible pressure and heat as you descend through the atmosphere.

Interesting Fact

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Neptune

It rotates backwards on an axis that is tilted to 98 degrees.

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6E1CE Comparing Objects in the Solar System

Student Journal Part I: Space Research Groups, continued Comets, Meteors, and Asteroids Comets Location in the Solar System

Interesting Fact

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Asteroids

Varies

Atmosphere

Composition

Meteor, Meteorites, Meteoroids

None

Frozen gas, rock, and dust

They range in size from dust to dwarf planet.

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6E1CE Comparing Objects in the Solar System

Student Journal Part II: SPACE Bingo

Directions: Write the answer to each clue as your teacher calls them out. Then mark your SPACE bingo card. Clue 1: The atmosphere is mainly nitrogen and oxygen. It is a terrestrial planet. Answer:

Clue 2: This object is made of frozen gas, rock, and dust. It can have a tail when it gets close to the Sun. Answer:

Clue 3: This terrestrial planet has no moon and is 58 million kilometers from the Sun. Answer:

Clue 4: This outer planet is blue due to methane at the top of its atmosphere. It also rotates backwards. Answer:

Clue 5: This is the group of objects held together by our Sun. Answer:

Clue 6: This object is what a meteoroid is called when it burns up in Earth’s atmosphere. Answer:

Clue 7: The largest mountain and largest canyon in the solar system are found on this planet. Answer:

Clue 8: These are the gas giants. Answer:

Clue 9: This is the larger version of a small rock in space. They vary in size from dust to dwarf planet. Answer:

Clue 10: This terrestrial planet is about 228 million km from the Sun. Answer:

Clue 11: This second gas planet has an extensive ring system. Answer:

Clue 12: This object is the largest object in our solar system. All the planets orbit around it. Answer:

Clue 13: This largest gas planet has an atmosphere made of mainly hydrogen. It has 67 confirmed moons. Answer:

Clue 14: This outer planet is farthest from the Sun at 4.5 billion km. Answer:

Clue 15: This is the new name for a meteoroid that falls to Earth and lands on Earth’s surface. Answer:

Clue 16: The Great Red Spot is a storm in this planet’s atmosphere. Answer:

Clue 17: This is the only planet known to support life. Answer:

Clue 18: Atmosphere is constantly stripped and replaced by solar winds on this planet. Answer:

Clue 19: This is the hottest planet. Answer:

Clue 20: These are the terrestrial planets. Answer:

Clue 21: This object varies in mass and size. It is a smaller version of an asteroid and is found in space. Answer:

Clue 22: This is the coldest planet. Answer:

Clue 23: This is the location in the solar system between the inner and outer planets where asteroids tend to cluster. Answer:

Clue 24: This planet is closest to Earth. It has a thick atmosphere that is mainly carbon dioxide and a small bit of nitrogen. Answer:

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6E1CE Comparing Objects in the Solar System

Student Journal Reflections and Conclusions 1.

How did astronomy change in the 19th and 20th centuries?

What key inventions have helped humans learn about our solar system?

What is the difference between a comet and an asteroid?

What is the difference between meteors, meteorites, and meteoroids?

Compare and contrast the inner and outer planets in the Venn diagram below. List at least two facts for each part of the diagram.

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STEMscopedia: COMPARING OBJECTS IN THE

SOLAR SYSTEM 6E1CE

Reflect Have you ever been outside on a cloudless night away from bright city lights? The sky is filled with seemingly endless stars. If you have ever seen a large, reddish star shining brightly, you may actually be looking at the planet Mars, Earth’s planetary neighbor. Did you know an expedition is in the works to send people to Mars? What would such a voyage entail? Would the risks be worth the benefits? Would you consider going? Why or why not? What is the solar system? The solar system is the Sun and all of the objects that orbit around the Sun due to its gravitational pull. The solar system is basically divided into two parts: the inner solar system and the outer solar system. The inner solar system consists of the rocky planets and the asteroid belt. The outer solar system is composed of the gas giant planets, the Kuiper belt, and the Oort Cloud. Various smaller objects such as dwarf planets, meteoroids, asteroids, and comets are also part of the solar system.

What Do You Know? Look at the chart below. It lists the characteristics of other planets in the solar system relative to Earth’s characteristics. Examine the column that compares distances from the Sun. Construct a line graph showing the distances of planets from the Sun in astronomical units. Planets should be on the x-axis and astronomical units on the y-axis. Make sure to include the title and label each of the axes. Then answer the questions that follow. Planet Diameter Mass Distance Length of Day Length of (compared (compared from Sun (in Earth Year (in to Earth) to Earth) (AUs*) hours or Earth days days) or years) Mercury 0.38 0.06 0.39 59 days 88 days Venus Earth Mars Jupiter Saturn Uranus Neptune

0.95 1.00 0.53 11.20 9.40 4.0 3.9

0.82 1.00 0.15 318.00 95.00 15 17

0.72 1.00 1.5 5.2 9.5 19 30

243 days 1.00 days 24.6 hours 10 hours 10.7 hours 18 hours 16 hours

225 days 1.00 years 687 days 11.9 years 29.5 years 84 years 165 years

*Note: An AU is an astronomical unit (149.6 million kilometers). That is the average distance during the year from the center of Earth to the center of the Sun.

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_______________________________________________________________________

Which planet is closest to Earth? 1. What do you notice about the distances between planets the farther out you go? 2.

Can you think of a reason why this might occur?

Why do you think there is such a big gap between Mars and Jupiter?

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The Sun: The Sun is the center of our solar system. It is a medium-sized yellow star. However, even being “only” average size, the Sun is so huge that approximately a million Earths could fit inside it. Our Sun is a ball of hot gases—about 75 percent hydrogen and 25 percent helium. A reaction called nuclear fusion caused by the Sun’s gravity results in the Sun giving off large amounts of light and heat. The Sun is composed of several parts. The core is the center of the Sun where nuclear fusion occurs. Moving outward, the next layer is the radiation zone. Energy there is passed on through electromagnetic radiation. The next layer is the convection zone, which transfers heat through the convection of hot gases. The following layer is the photosphere, which means “sphere of light” and is what we think of as the surface of the Sun. It gives off immense amounts of visible light. Next comes the chromosphere, which composes the inner atmosphere of the Sun. The final and hottest layer is the corona, which is the outer atmosphere of the Sun and reaches temperatures up to 2,000,000 degrees Celsius! Sunspots and solar flares are two other features from the surface of the Sun.

Look Out Sunspots and solar flares are often confused. Although they can be connected, they are two different spectacles. Sunspots are dark areas on the surface of the Sun where the temperature is lower, which results in those regions giving off less light. Solar flares are sudden flashes of bright light that release large amounts of energy in the forms of light and heat. Solar flares often originate in the sections around sunspots because of the strong magnetic fields found there. The Inner Planets Mercury: Mercury was named for the messenger god in Roman mythology. Mercury is the closest planet to the Sun. In addition, it is the smallest planet in the solar system. (This honor used to belong to Pluto, but Pluto’s status was downgraded from planet to dwarf planet in 2006.) In fact, Mercury has only one-third of the diameter of Earth and six percent of Earth’s mass! It seems to move across the sky very rapidly because it makes a complete revolution around the Sun (a year) in only 88 Earth days. (This is probably why it was named after a speedy messenger god.) A peculiar fact about Mercury is that its day takes almost as long as its year—59 Earth days for one rotation! Mercury has no moons. In fact, Earth’s moon is 71 percent of the size of Mercury! Mercury also looks more like the Moon than Earth.

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It is a rocky, lifeless planet, covered with craters and seems to contain a lot of iron. It is very dense, second only to Earth in density in our solar system. Mercury has an extremely thin atmosphere, which, along with its slow rotation, contributes to its extreme swings in temperature. The side of Mercury that faces the Sun reaches temperatures around 425 degrees Celsius, while the surface away from the Sun drops to -170 degrees Celsius. Gravity on Mercury is only 38 percent of Earth’s, so a person who weighs 100 pounds on Earth would only weigh 38 pounds on Mercury. Venus: Venus was named for the goddess of love and beauty, probably due to its bright beautiful light in the night sky. Venus is sometimes called the “Morning Star” or the “Evening Star” because it can be so bright during those times. Venus is the second planet from the Sun. It is very similar to Earth in terms of size. Its diameter is 95 percent of Earth’s and its mass is 82 percent of Earth’s. Venus has a density that is nearly identical to Earth’s, and its gravity is about 90 percent of what you would find on Earth. A 100-pound person on Earth would weigh 90 pounds on Venus. In fact, Earth and Venus are so similar that Venus is sometimes called Earth’s twin. However, there are many differences between the two planets. Venus has no moons. Venus completes a revolution around the Sun in 225 Earth days. Venus has a very strange rotation. It completes a rotation in 243 Earth days. That means a day on Venus is longer than a year! Also, Venus rotates backwards! The atmosphere on Venus is about 90 times thicker than Earth’s atmosphere. Venus is covered in thick clouds composed of mostly carbon dioxide as well as a layer of sulfuric acid clouds. Due to the greenhouse effect, Venus has the hottest surface temperature in the solar system at close to 500 degrees Celsius! Earth: Earth is the third planet from the Sun and the only planet in our solar system that is not named after a Roman god or goddess. It means “land” or “ground” in Old English. It is a distance of one astronomical unit from the Sun. It has a diameter of 12,800 kilometers, a mass of 5.97 x 1024 kilograms, and a gravity of 9.8 newtons per kilogram. It has an average surface temperature of 15 degrees Celsius. It has a dense atmosphere composed mostly of nitrogen followed by oxygen and trace amounts of other elements. Earth rotates every 24 hours and revolves around the Sun every 365.25 days. Earth is a unique planet because it contains water in solid, liquid, and gaseous forms. Earth has one moon that orbits Earth every 27.3 days.

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STEMscopedia: COMPARING OBJECTS IN THE

SOLAR SYSTEM

Earth’s Moon: The Moon is Earth’s natural satellite. It revolves around Earth at a distance of 384,400 kilometers. It is composed of rocky material that is much less dense than Earth’s material. Its diameter is one-fourth of Earth’s, and its mass is about one percent of Earth’s mass. Its gravity is one-sixth as strong as Earth’s gravity. A 100 pound person would only weigh about 17 pounds on the Moon. Because the Moon has such a small mass, it does not have enough gravity to attract and keep an atmosphere. Therefore, it is covered with craters from meteors hitting its surface. The Moon, along with the Sun, is responsible for tides of Earth. Just as Earth orbits the Sun, the Moon revolves around Earth. An interesting fact about the Moon is that its rotation and revolution periods are exactly the same, which means the same side of the Moon always faces Earth! Mars: Mars is named for the Roman god of war, probably due to its blood red color. It is the fourth planet from the Sun. It is about 1.5 astronomical units from the Sun. Compared to Earth, Mars has 53 percent of Earth’s diameter, about 10 percent of Earth’s mass, and 38 percent of its gravity. It is the second smallest planet in the solar system, only larger than Mercury. Mars rotates every 24.6 hours, making a Martian day very comparable to an Earth day. Being farther from the Sun, Mars completes a revolution around the Sun every 687 days. Mars has two moons, Phobos and Deimos, which are very small. A prevailing theory is that the moons are asteroids captured by the gravity of Mars as they passed. Just like the other inner planets, Mars is a rocky planet. Its surface is covered in deserts, mountains, and valleys. The largest volcano in the solar system, Olympus Mons, is located on Mars. It is 25 kilometers high and approximately as wide as the state of Arizona! Mars has a very thin atmosphere that consists mostly of carbon dioxide. Temperatures on Mars are usually below freezing, averaging around -50 degrees Celsius. Mars has polar ice caps that contain some frozen water and a tilted axis that results in seasons like Earth. Scientists are planning a manned expedition to Mars in 2024 called Mars One, with the intention of starting a colony there. The Outer Planets Jupiter: Jupiter was named after the leader of the Roman gods. It is the fifth planet from the Sun and the nearest representative of the outer solar system. Jupiter is the largest planet in our solar system, and it is so massive that it is more than twice as large as the other seven planets combined! Jupiter’s diameter is 11.2 times that of Earth’s, its mass is about 318 times larger than Earth’s, and its volume is 1,321 times larger than Earth’s. In addition, Jupiter possesses 240 percent of Earth’s gravity. Interestingly, Jupiter is only about 25 percent as dense as Earth. It is about 5.2 astronomical units from the Sun. Jupiter spins extremely rapidly on its axis, making a day on Jupiter last only 10 Earth hours—the shortest day in the solar system. A year on Jupiter is 4,333 Earth days or almost 12 Earth years. Jupiter has 62 known moons! Its four largest and best known moons are Io, Ganymede, Europa, and Callisto. Unlike the four rocky inner planets, Jupiter is a gas giant. Its atmosphere is mostly composed of hydrogen and helium.

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SOLAR SYSTEM

Orange, brown, red, and white clouds cover the surface of Jupiter. The most famous feature of Jupiter is the Great Red Spot. It is a huge hurricane, so large that it could fit three Earths inside of it! Jupiter has three thin rings that surround it. It also has a very strong magnetic field. The temperature on Jupiter is very cold at the surface and very hot at the center. It is -145 degrees Celsius at the surface, and the core is 24,000 degrees Celsius! Jupiter is usually the third brightest object in the night sky, after the Moon and Venus. Saturn: Saturn was named after the Roman god of agriculture, liberation, and time. Saturn is the sixth planet from the Sun and is approximately 9.5 astronomical units from the Sun. Saturn is the second largest planet in the solar system and is about 10 times the size of Earth. Like all of the outer planets, Saturn is a gas giant with an atmosphere consisting mostly of hydrogen and a small percentage of helium. It is the least dense of all the planets. Like Jupiter, Saturn spins rapidly. A day on Saturn is equivalent to only 10 hours and 42 minutes on Earth. However, a year on Saturn is 29.5 Earth years. Saturn’s gravity is similar to Earth’s gravity. Saturn’s average surface temperature is a chilly -139 degrees Celsius. Saturn is best known for its prominent rings. The rings are composed of ice and rock pieces in varying sizes from microscopic to the size of a large house. They are 250,000 kilometers wide but only about 100 meters thick. Galileo first viewed Saturn’s rings through a telescope in 1610. Like Jupiter, Saturn possesses many moons—53 of them! Titus, Phoebe, Iapetus, Rhea, Tethys, Mimas, Enceladus, Hyperion, and Pan are just a few of them. Saturn is like its own miniature solar system! Uranus: Uranus was named for the Roman god of the sky. It is a light sky blue color. It is so far away that it was not discovered until modern times, in the year 1781. It is 19 astronomical units from the Sun. Like Jupiter and Saturn, Uranus is a gas giant, composed mainly of hydrogen and a smaller percentage of helium. It has about 90 percent of the gravity of Earth. Uranus possesses 27 moons, all of which are only a fraction of the size of Earth’s Moon. The average temperature on Uranus is about a frigid -200 degrees Celsius. An interesting fact about Uranus is that it rotates backwards. It takes 18 Earth hours for one rotation for one day. One revolution around the Sun (one year) takes 84 Earth years. Neptune: Because of Neptune’s deep blue color and because it is so far out in deep space, it was named for the Roman god of the deep blue sea. It is 30 astronomical units from the Sun! It is so far away that it was not discovered until 1846. A day on Neptune is 16 Earth hours long, and a year is 165 Earth years! Gravity on Neptune is just slightly more than on Earth. A 100-pound person from Earth would weigh about 114 pounds on Neptune. Neptune has small rings and 13 moons. Most of its moons are tiny—only a couple hundred kilometers, with the exception of Triton. The temperature of Neptune is approximately -200 degrees Celsius.

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SOLAR SYSTEM

What Do You Think? Pick three planets to compare and contrast. Then write and answer three questions about the planets you chose.

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Other Components of the Solar System Asteroids and the Asteroid Belt: Asteroids are odd-shaped bodies composed of rocky material and sometimes metals. Most asteroids are smaller than a kilometer but some are very large. For example, the most massive asteroid is called Ceres, and it is 933 kilometers in diameter. Most asteroids are found in the asteroid belt, which is located between Mars and Jupiter. However, some travel throughout the solar system and approach planets. In fact, it is believed that an asteroid hit the Yucatán Peninsula 65 million years ago and caused a mass extinction on Earth. Comets: Comets are bodies that travel throughout the solar system. Most comets originate in the Kuiper Belt near the outer edge of the solar system. Comets have four components: nucleus, coma, corona, and tail. The nucleus is in the center and is made out of ice, rocks, and dust. The coma is made from evaporated gases and dust and surrounds the nucleus. The corona is a layer of hydrogen gas surrounding the coma. The tail spreads out behind the comet. It is composed of gas ions. The solar wind pushes the ions out farther and farther behind the comet as it approaches the Sun, sometimes causing the tail to be millions of kilometers long. Comets travel in very elliptical orbits. Most comets seem to follow a random timetable, although a few, like Halley’s Comet, are predictable. Meteoroids, Meteors, and Meteorites: What are the differences among meteoroids, meteors, and meteorites? Well, one celestial body can be all three at different times along its path. Meteoroids are small pieces broken off asteroids or comets. They travel through space. When meteoroids enter Earth’s atmosphere, they become meteors. They become heated by the friction of Earth’s atmosphere and begin to glow and look like rapidly moving stars. This is why people sometimes call them “shooting stars.” Meteorites are meteors that do not burn up completely and impact Earth’s surface. The Kuiper Belt: The Kuiper Belt is a very distant region of the solar system that extends to more than 1,000 astronomical units. It has many asteroids, comets, and dwarf planets. Many celestial objects are simply classified as KBOs, or Kuiper Belt Objects.

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STEMscopedia: COMPARING OBJECTS IN THE

SOLAR SYSTEM

Connecting With Your Child The planets in the solar system are vastly different sizes. Review the chart showing characteristics of planets relative to Earth and examine the column that lists the diameters of the planets. Create a solar system with the planets constructed according to the correct ratios. You can find objects that already exist, you can make your own planets, or you can use a combination of both. (Hint: Start with extremely small objects for the smallest planets or the sizes of the larger planets can be difficult to find or create.) If you are not ready to stop after you are done creating planets, you may continue the project by creating other objects in the solar system. The asteroid belt, comets, moons, and dwarf planets are just a few ideas of celestial bodies you might enjoy adding to your solar system. Remember to keep them to scale! After you have completed your solar system, take a picture of your solar system. Then answer the following questions: 1.

Which was the most difficult planet to build or find? Why?

When you look at the representations of the planets next to one another, did anything surprise you about the size or scale of the planets? What and why?

Which was the most fun planet to construct or find? Why?

What extra features did you add to your solar system or which features would you add to your solar system if you could? Why?

Explain something you learned by working on this project.

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6E1CE Comparing Objects in the Solar System

Reading Science Name:

Date:

Group:

Asteroids, Comets, and Meteoroids 1.

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune; Most people have studied the eight planets of our solar system plus the Sun and Moon. What other objects are major components of our solar system? Comets, asteroids, and meteoroids!

What are asteroids? Asteroids are oddly shaped bodies that orbit the Sun but are too small to be planets. Asteroids are usually composed of rocky material—like the four inner planets. Sometimes they are made of metal. Where are asteroids found? The vast majority of asteroids are found in the asteroid belt, which is located between Mars and Jupiter. Most asteroids are smaller than a kilometer in diameter, but some are quite large with diameters greater than 300 km. There are millions of small asteroids and between one and two million larger asteroids that possess diameters over the size of 0.5 km. Ceres, for example, is a large object in the asteroid belt that may be a dwarf planet, an asteroid, or both. Ceres has a diameter of 975 km and a mass of 9.4 x 1020 kg. Asteroids may have had a huge influence on life on Earth since it is widely believed that 65 million years ago, a large asteroid hit the Yucatan Peninsula, creating a crater almost 200 km wide! The impact of that asteroid is the probable cause of a mass extinction here on Earth.

What are comets? Comets are bodies composed of ice, dust, and rock. Comets are thought to originate in two places—the Oort Cloud (a cold cloud of gases almost to the outside edge of the solar system) and the Kuiper Belt (an area outside the orbit of Neptune, full of rocks, ice, and small celestial bodies). There are four major parts of a comet—nucleus, coma, corona, and tail. The nucleus is made of solid ice, rock, and dust. The coma is composed of evaporated gases and dust. It surrounds the nucleus and is many times greater in size. The nucleus and the coma form the comet’s “head.” The corona is a layer of hydrogen gas that surrounds the coma. The tail is the final part of the comet. It is made of gas ions that are pushed out behind the head by solar wind. Comets have a variable size, depending upon how close they are to the Sun. They are generally less than 10 km wide, but as they approach the Sun, their tails can be millions of kilometers long. This happens because as comets approach the Sun, ice is transformed to gases that stretch out away from the core of the coma due to the solar wind. Some comets in our solar system orbit the Sun regularly (like Halley’s Comet every 75 years), but others are unpredictable.

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6E1CE Comparing Objects in the Solar System

Reading Science 4.

What are meteoroids? Many people have difficulty distinguishing between meteoroids, meteors, and meteorites. Most meteoroids are small chunks of asteroids or comets that have broken off. Meteors are meteoroids that enter Earth’s atmosphere. The friction caused by Earth’s atmosphere heats and then burns up the meteor, making them glow brightly. They have earned the nickname “shooting stars” because they glow brightly and streak across the sky. Meteorites are meteoroids that enter Earth’s atmosphere and do not completely incinerate. They survive Earth’s atmosphere and actually hit the surface of Earth. How common are meteors and meteorites? Surprisingly, if you go out to stargaze, you can see a meteor (“shooting star”) about every 10-15 minutes. Scientists believe there are approximately 5 to 10 minor meteorite strikes per year and a major meteorite strike about once every five years. Considering all of the debris in space, Earth’s atmosphere is pretty efficient at protecting Earth. Most of the meteorites that hit Earth’s surface have a mass of 10 kg or less. In addition, because 75 percent of the surface of our planet is covered in water, most of the meteorites drop into large bodies of water. However, Barringer Meteorite Crater in Arizona is over 1.5 km wide and 175 m deep. Scientists believe the huge crater was created about 50,000 years ago by a meteorite approximately 50 m in diameter.

Asteroids, comets, and meteoroids are interesting and sometimes elusive components of our solar system. Why should we study them? We can discover if they carry life from one location to another. We can investigate the composition of the Oort Cloud. We can decide if we can land a spacecraft on them. We can learn to protect Earth from them. The more questions we ask, the more we can learn.

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6E1CE Comparing Objects in the Solar System

Reading Science 1.

Which of the following is an incorrect statement regarding meteors, meteorites, and meteoroids? A.

Meteorites make impact with Earth’s surface.

The same object could be a meteoroid, a meteor, AND a meteorite—just at different times and at different locations.

Meteorites are generally larger than meteoroids.

Most meteors get burned up in Earth’s atmosphere.

Why is it difficult to accurately state how long a specific comet is? A.

Comets are very far away.

Scientists do not have capabilities for estimating comet length.

Comets travel too fast to be measured.

The length of a comet varies depending upon how close it is to the Sun.

Which of the following is a similarity among asteroids, comets, and meteoroids? A.

They are remnants of the formation of the solar system.

None of them possess atmospheres of their own.

They may be seen from Earth with a telescope.

All of the above.

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6E1CE Comparing Objects in the Solar System

Reading Science 4.

I usually form in the Oort Cloud. I have a head and a tail. As I approach the Sun, my tail gets longer. What am I? A.

Asteroid

Meteor

Comet

Meteorite

Why do you think a meteor is referred to as a “shooting star”? A.

It is as hot as a star as it burns up in Earth’s atmosphere.

It has the same composition as a star but is just smaller.

It is a streak of white light moving across the sky that looks like a shooting star.

It goes through the life cycle of a star but very rapidly.

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6E1CE Comparing Objects in Our Solar System

Math Connections Name:

Date:

Group:

The Sun is at the center of our solar system. Its strong gravitational pull holds eight planets, as well as asteroids and other celestial objects, in orbital paths around it. The planets in the solar system revolve around the Sun in an orbital path. Each planet rotates (spins) on an axis. Orbital Period and Distance from the Sun Mercury Venus Earth Mars Jupiter Saturn

Uranus

Neptune

Distance from Sun (x 106 km)

58.3

107.7

149.6

227.3

777.9

1,413.7

2,860.0

4496.9

Orbital Period (days)

224.7

365.2

687

4331

10,747

30,589

59,800

In the space provided below, create a scatterplot illustrating the relationship between the orbital period and distance from the Sun of each planet in the solar system. Planet's Distance from the Sun Versus Orbital Period 4500 4275 4050

Distance from the Sun (x 106 km)

3825 3600 3375 3150 2925 2700 2475 2250 2025 1800 1575 1350 1125 900 675 450 225 0 60,000

50,000

40,000

30,000

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20,000

10,000

5000

4000

700

600

500

400

300

200

100

Orbital Period (days)

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6E1CE Comparing Objects in Our Solar System

Math Connections 2.

Connect the points and describe the trend. Why do you think the planets’ distances from the Sun and orbital periods are related in this way?

All of the solar system’s planets, except Mercury and Venus, have moons. Moons are smaller celestial objects that orbit planets.

Mercury

Diameter of Planets and Number of Moons Venus Earth Mars Jupiter Saturn

Uranus

Neptune

Diameter 4,879 12,104 12,756 6,792 142,984 120,536 51,118 49,528 (km) Number of 0 0 1 2 67 62 27 14 Moons 3. In the grid below, create a scatterplot comparing each planet’s number of moons and that planet’s diameter. Diameter of Planets Versus Number of Moons 140,000 130,000 120,000 110,000

Diameter (km)

100,000 90,000 80,000 70,000 60,000 50,000 40,000 30,000 20,000 10,000 0 70

Number of Moons

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6E1CE Comparing Objects in Our Solar System

Math Connections 4.

What trend do you see in the data as it refers to the number of moons orbiting a planet and the diameter of that planet? Explain your observation.

List the planets in order from the one with the smallest diameter to the one with the largest diameter.

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6E1CE Components of Our Solar System

Writing Science Name:

Date:

Group:

LOOK

THINK Think about the objects that make up our solar system. WRITE Explain the ways in which planets differ from asteroids, comets, and meteoroids, and describe how gravity governs their motion. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E1CE Components of Our Solar System

Writing Science

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6th Grade Earth and Space Science

6E1D

Motion in the Solar System

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6E1D Motion in the Solar System

Student Handout

Name:

Date:

The Attraction Tango 1.

What forces are acting on the rolling ping-pong ball?

Draw a diagram of a ball on a string model. Label the direction of the forward motion and the gravitational force.

What does the model tell us about the effect of gravity on the orbit of a body in motion around the Sun?

What will happen to the ball when it is released from its circular movement? Why?

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6E1D Motion in the Solar System

Student Journal Name:

Date:

Group:

Gravity Background 1.

What two factors keep the planets in orbit?

What would happen to a planet in our solar system if the Sun’s gravitational pull suddenly stopped?

How many objects must be present in a system to demonstrate gravity as a force of attraction?

True or false (circle one): Distance between masses affects the amount of gravitational pull.

True or false (circle one): Mass affects the force of gravity.

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6E1D Motion in the Solar System

Student Journal Part I: The Bigger, The Better 1.

What is the appropriate location of the student/object when Groups A and B are of equal mass? Why?

How did having half of the students in Group A move to join Group B affect the model?

What is the appropriate location of the student/object when Group B has a greater mass than Group A? Why?

What would be the appropriate location of the student/object if Group A had a larger mass than Group B? Why?

What did this tell you about the strength of the force of the two groups?

As mass increases, the strength of gravitational force of the mass ____________________.

As mass decreases, the strength of gravitational force of the mass ___________________.

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6E1D Motion in the Solar System

Student Journal Part II: Big, Bigger, Biggest 1.

Complete the table by listing the objects in order from most gravitational force to least gravitational force using the Student Reference Sheet: Solar System Objects. Gravitational Force most

Celestial Object 1. 2. 3. 4. 5. 6. 7. 8.

least

9. 10.

What is the largest object in our solar system? __________________________________

Why does this object have the most gravitational pull?

How many objects have more gravitational pull than Earth? Explain.

If Earth’s Moon was added to this ranking, where do you think it would fit? Why?

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6E1D Motion in the Solar System

Student Journal Part III: How Far is Too Far? Background 1.

What is Newton’s universal law of gravitation?

Why are magnets used to investigate gravity?

Part IV: Plan Your Model 1.

My question of inquiry:

The hypothesis:

What is the independent variable (also known as the manipulated variable)?

What is the dependent variable (also known as the responding variable)?

What materials, equipment, and technology will be needed for this model?

List all safety precautions that must be taken.

You will carry out the investigation by following the procedures on the Student Guide.

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6E1D Motion in the Solar System

Student Journal Part IV: Plan Your Model Collect, Record, and Organize Your Data Fill in the data table below as you collect your data. Layers of Cardboard

Response to Magnet

Thickness of Cardboard (mm)

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6E1D Motion in the Solar System

Student Journal Part V: Implement Your Model Analyze Data 1.

What occurred to the distance between the paper clip and magnet as the pieces of cardboard were added to the setup?

What effect did adding the pieces of cardboard have on the force of attraction?

How was the attraction of the paper clip to the magnet affected by the increase in distance between the paper clip and the magnet?

If the magnet represents an object exerting the force of gravity and the paper clip represents an object being pulled by the gravity, what effect does distance have on the strength of the force?

How are models with magnets a good way to investigate gravitational force?

What are the limitations of using magnets to investigate gravitational force?

How does this model relate to our solar system? Give an example.

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6E1D Motion in the Solar System

Student Journal Reflections and Conclusions 1.

Is the hypothesis supported by the data? Explain.

How did the results reveal a relationship between the independent and dependent variables?

Where could errors have been made while collecting or organizing data?

What do you conclude about this model?

What would you do differently if you were to conduct this experiment again?

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STEMscopedia: MOTION IN THE SOLAR SYSTEM 6E1D Reflect As you are sitting and reading this, are you moving? Absolutely! Every organism, building, and structure on Earth is always moving. How fast, do you think? Just to be able to make one full rotation on Earth’s axis, we are all continually moving at almost 1,600 kilometers per hour! That’s roughly 1,000 miles per hour!

The Earth completes one rotation every day. This is what provides us with the day-night cycle.

Note: The orbital path around the Sun is not completely elliptical. To better represent the orbit, the Sun should not be in the exact middle as depicted above.

Earth in Motion In addition to rotating every day, Earth is also constantly in motion while orbiting the Sun. An orbital path is the gravitationally curved path of an object around a point in space. How long does it take to make one revolution around the Sun? Roughly 365 days, or one year.

Look Out Why do we have a leap year? Have you ever wondered why there is a leap year every four years? The Earth takes 365.25 days to complete its revolution around the Sun. However, we consider a year to be only 365 days. To make up for this extra quarter day, every four years an extra day is added to the calendar. (Four quarters equals one whole!) That day, February 29, is considered Leap Day. Look at the model of the solar system on the right. What is the model trying to represent? All planets in the solar system, along with other celestial objects, orbit the Sun. The distance the planet covers while orbiting the Sun is called an astronomical unit (AU). How do you think the astronomical units of all the planets compare?

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STEMscopedia: MOTION IN THE SOLAR SYSTEM The model in the picture works to illustrate the differences in each planet’s orbit. The closer the planet is to the Sun, the shorter one revolution is. Similarly, the farther the planet is from the Sun, the longer the revolution.

The Sun’s gravity is so strong that it holds all the planets in constant orbit simultaneously!

Planets in Orbit Mercury has the shortest trip around the Sun, taking about 88 Earth days to complete one orbit. Neptune, on the other hand, takes almost 165 Earth years to complete its orbit. That means that no person will ever live long enough to witness Neptune complete one revolution! Earth completes its 93-million-mile journey around the Sun every year. How fast do you think Earth has to move in order to complete its orbit? About 18.5 miles per second. That means we are currently zooming around the Sun at 66,600 miles per hour!

What Do You Think? Why do you think the planets are held in this constant motion around the Sun?

Gravity is the force that causes objects with mass to attract one another. The larger object is able to exert more gravity on the smaller object. For example, we are pulled to Earth’s surface because Earth has a larger mass than we do. 72

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STEMscopedia: MOTION IN THE SOLAR SYSTEM

The Sun’s gravity pulls more than just planets in. What other celestial objects do you think the Sun’s gravity impacts?

The Sun is so massive that its gravity pulls all the objects in the solar system toward it. Inertia is the tendency of a physical object to remain still or continue moving, unless force is applied. Since the planets are already moving along their orbital paths, it would take an incredible amount of force to stop them or to knock them out of orbit.

Look Out Though the Sun is obviously the most massive object in the solar system, it is definitely not the only object that holds others in orbit. What are some examples that you can think of? While Earth orbits the Sun, the Moon orbits Earth. Once again, the object with less mass (the Moon) orbits the object with larger mass (Earth). The orbiting of the Moon around Earth gives us the lunar phases. The lunar cycle is the Moon’s repeated pattern of movement and changes in appearance due to its position relative to Earth and the Sun.

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STEMscopedia: MOTION IN THE SOLAR SYSTEM What Do You Think? In the space below, draw the Sun, Earth, and Moon. Construct a model of the interaction of gravity and inertia by drawing dashed lines to demonstrate the gravity celestial objects display on each other.

Connecting With Your Child To help your child learn more about the interaction between gravity and inertia in the solar system, set up a few inertia models in your backyard. (Inertia is the tendency of a physical object to remain still or continue moving, unless force is applied.) Find two balls of different size and mass. Place the heavier ball in the middle and then roll the lighter ball toward it so they collide. Discuss with your child what they observed. Next, place the lighter ball in the middle and then roll the heavier ball toward it so they collide. Discuss with your child what they observed. When the lighter ball collides with the heavier ball, the heavier ball will remain still. However, when the heavier ball collides with the lighter ball, the lighter ball with move. Relate this to the planets in the solar system. In order to move a massive object like a planet, an even heavier object would have to collide with it. Here are some questions to discuss with your child: 1. What is gravity? 2. What is inertia? 3. How does gravity and inertia govern the motion of objects in the solar system?

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6E1D Motion in the Solar System

Reading Science Name:

Date:

Group:

Rotation and Revolution 1.

Have you ever wondered what it was like on the other side of the world as you were getting ready for bed? Perhaps you have wondered what season it was in Australia as you were sweating on a hot summer day. The first question can be answered by examining the tilt of Earth on its axis. The second answer comes from understanding the position of Earth during its revolution around the Sun.

First, let’s discuss what an axis is. Picture an imaginary pole running from the North Pole through Earth’s center all the way to the South Pole. This imaginary pole is called an axis. Earth rotates on its axis, taking about 24 hours to complete one entire spin. Thus, one complete rotation cycle results in 12 hours of daylight and 12 hours of night, as different parts of Earth are rotated into the Sun’s light. Have you ever stood outside and watched as the Sun sinks below the horizon? You have actually been witnessing Earth’s rotation. The Sun is not moving, although it appears to be. Earth is moving! The rotating Earth also makes the other stars in the night sky seem to glide across the sky when, in fact, it is the rotation of Earth on its axis that makes them appear to move. At any given time during the 24-hour rotation, half of Earth is in sunlight and half of Earth is in darkness. This means as you get ready for bed, somewhere on the other side of Earth, someone is just getting up.

Think of Earth as a ball with a rod through it, representing the axis. This makes it easier to visualize Earth’s orientation in space relative to other objects like the Sun. Now consider the Sun as another ball. Imagine the Sun located in the center of a disk, somewhat like a Frisbee. The planets in the solar system would be positioned on the Frisbee but at varying distances from the Sun. The area we are visualizing as a Frisbee is actually called the plane of the ecliptic. It is the plane of Earth’s orbit around the Sun. Earth’s axis is not oriented perpendicular to the plane of its orbit, but rather it is tilted at 23.5 degrees from the perpendicular. Why is this an important detail? This orientation in space, relative to the Sun, has great influence on Earth’s seasonal changes.

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6E1D Motion in the Solar System

Reading Science 4.

Now, to address our second question. What would cause it to be summer in North America and winter in Australia? We have just learned that rotation is the spinning of Earth on its axis that causes day and night. We also learned that the orientation of Earth’s axis is tilted 23.5 degrees perpendicular of the plane of the ecliptic. Now picture this: While Earth is rotating, it is also revolving around the Sun in a nearly circular path called an orbit. This revolution takes one year, or 365 days, to complete. During this one year, Earth experiences four different seasons. The seasons are summer, fall, winter, and spring, but they do not happen at the same time in the northern and southern hemispheres. In June, July, and August, Earth’s tilt positions the northern hemisphere so that sunlight hits it more directly. The northern hemisphere has a larger number of daylight hours, causing a summer season. During that period of time, the southern hemisphere is angled so the sunlight is not as direct. The number of daylight hours is less, causing the opposite winter season. This explains why the northern and southern hemispheres experience different seasons.

The next time you watch a sunset or sunrise, think about the rotation of Earth. Remember that you are experiencing the same thing that is causing day and night. On the next scorching hot summer day or frigidly cold winter day, think about the tilt of Earth on its axis. Remember how its position in Earth’s revolution around the Sun brings you the seasons.

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6E1D Motion in the Solar System

Reading Science 1.

In the third paragraph, what word or phrase gives you a clue to what the word perpendicular means? A.

Somewhat like a Frisbee

Relative to the Sun

Instead, it is tilted

Orientation in space

Which of the following effectively summarizes the second paragraph? A.

The orientation in space, relative to the Sun, is the cause of Earth’s seasonal changes.

There is an imaginary pole running through the center of Earth from the North Pole to the South Pole, which is called an axis.

We also learned that Earth’s axis is tilted 23.5 degrees perpendicular of the plane of the ecliptic.

The northern hemisphere has more daylight hours.

According to the passage, what is rotation? A.

The constant spinning of Earth on its axis

The movement of Earth through space around the Sun

An orbital path shaped more like a circle than an oval

The four seasons: summer, fall, winter, and spring

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6E1D Motion in the Solar System

Reading Science 4.

Which of the following statements best shows why it would be winter in the southern hemisphere and summer in the northern hemisphere? A.

Earth’s tilt positions the northern hemisphere to receive more of the Sun’s direct rays.

Earth’s tilt positions the southern hemisphere to receive more of the Sun’s direct rays.

Earth’s tilt exposes the northern hemisphere to longer periods of daylight.

Both A and C are correct.

The rotation of Earth takes approximately _____ to complete, and the revolution of Earth takes approximately _____ to complete. A.

1 day, 30 days

12 hours, 24 hours

365 days, 24 hours

24 hours, 365 days

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6E1D Motion in the Solar System

Math Connections Name:

Date:

Group:

Gravity is a force of attraction between two or more masses. Everything that has mass has gravity. The more mass an object has, the stronger its gravitational pull on other objects is. 1.

Use this information above to help you fill in the column labeled Gravity. (Answer options are to the right.) Think about how ordering the planets by mass will help you solve the problem. Planet Jupiter Sun Earth Saturn Mars Neptune Venus Mercury Uranus

Mass (x 1024 kg) 1,898 1,988,500 5.97 568 0.642 102 4.87 0.330 86.8

Gravity (m/s2)

Answer Bank a. 3.7 b. 11.0 c. 9.0 d. 274.0 e. 23.1 f. 9.8 g. 3.7 h. 8.9 i. 8.7

A planet’s gravitational force is affected by its proximity to other planets and the Sun. A planet’s gravity in relation to Earth’s is used to help calculate how much something weighs on that planet. Celestial Body Earth Moon Venus Mars Jupiter Saturn Uranus The Sun

Ratio of Gravity in Relation to Earth 1 0.166 0.91 0.38 2.14 0.91 0.86 28

I f the Sun has 28 times more gravity than Earth, what is your weight on the Sun? Create an equation to solve the problem.

ow much would a person weighing 150 H pounds on Earth weigh on Uranus?

he Space Shuttle weighed 165,000 pounds T on Earth. How much would it weigh on the Moon?

There is a plan to send people to Mars by the year 2030. Why would it be necessary to use a conversion like this when planning for the trip? (Answer on the back of this sheet.)

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6E1D Motion in the Solar System

Writing Science Name:

Date:

Group:

LOOK

THINK One popular ride at theme parks and carnivals is well liked because it does not require passengers to wear a seatbelt or harness. The ride is known by many different names, such as “Graviton” and “Starship,” however, the scientific principles at work remain the same. The ride starts off spinning slowly and increases in speed over time. After a while, the ride reaches a great enough speed that riders feel pressure pushing them against the walls of the ride. This allows riders to ride upside down or even sideways without falling off. The pressure felt by riders is actually referred to as inertia. WRITE Explain the role inertia and gravity play in the “Graviton” ride in relation to the solar system. Then describe a model that can be used to explain how gravity and inertia interact to govern the motion of objects in the solar system. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E1D Motion in the Solar System

Writing Science

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6th Grade Earth and Space Science

6E2ABC

Positions of the Earth, Moon, and Sun

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6E2ABC Positions of the Earth, Moon, and Sun

Student Handout

Name:

Date:

Directions: Sketch both of your objects as they appear before you. Do not move your objects! You will rotate around your objects in order to draw them from all sides.

Drawing 1

Drawing 2

Drawing 3

Drawing 4

Were all four of your drawings the same? Why not?

Did the objects change their appearance? Why not?

Relate this to the motion of the Sun, Earth, and Moon.

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6E2ABC Positions of the Earth, Moon, and Sun

Student Journal Name:

Date:

Group:

Part I: Phases of the Moon 1.

Draw the portion of the Moon that is lit when you are facing the light source. If you are Earth, where is the Sun (light source) in relation to the Moon at this phase?

Draw the portion of the Moon that is lit after you have rotated one-eighth of a turn to your left. Is the Moon moving toward or away from the Sun?

Draw the portion of the Moon that is lit when your right shoulder is pointed toward the light source. How much of the Moon is lit and seen from Earth?

Draw the portion of the Moon that is lit after you rotated a one-eighth turn to your left. Is the amount of the Moon lit getting larger or smaller?

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6E2ABC Positions of the Earth, Moon, and Sun

Student Journal 5.

Draw the portion of the Moon that is lit when you are standing with your back to the light source. How much of the Moon facing Earth is lit?

Draw the portion of the Moon that is lit after you rotated a one-eighth turn to your left. Is the Moon moving toward or away from the Sun?

Draw the portion of the Moon that is lit when your left shoulder is pointed toward the light source. How much of the Moon is lit and seen from Earth?

Draw the portion of the Moon that is lit after you rotated a one-eighth turn to your left. Is the lit portion of the Moon getting larger or smaller?

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6E2ABC Positions of the Earth, Moon, and Sun

Student Journal Part II: Eclipse 1.

Draw a diagram to show the alignment of the Earth-Sun-Moon system and the effect on Earth of a solar eclipse. Label your diagram “Solar Eclipse.”

Draw a diagram to show the alignment of the Earth-Sun-Moon system and the effect on Earth of a lunar eclipse. Label your diagram “Lunar Eclipse.”

How could you use your diagrams of the eclipses as models to describe why eclipses occur?

Do more people see a solar eclipse or a lunar eclipse? Explain.

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6E2ABC Positions of the Earth, Moon, and Sun

Student Journal Part III: Seasons Data Table

Position

Description of Light on Globe

Season in Northern Hemisphere

A B C D E F G H

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6E2ABC Positions of the Earth, Moon, and Sun

Student Journal Part III: Seasons, continued 1.

At Position C, how was the amount of light different in the two hemispheres?

Position C shows Earth in the month of December. What season would it be in December in the southern hemisphere?

Position G, how was the amount of light different in the two hemispheres?

What month is Earth in at Position G? How do you know?

Position A and Position E have Earth receiving equal amounts of sunlight in the northern and southern hemispheres. What seasons occur at these points? Why?

At which location does the south pole receive 24 hours of daylight?

At which location does the north pole receive 24 hours of darkness?

Is Earth closer to the Sun at any one point than at other points in this model?

What two things cause seasons on Earth?

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6E2ABC Positions of the Earth, Moon, and Sun

Student Journal Reflections and Conclusions 1.

How can you use the revolution motions within the Sun-Earth-Moon system to explain the predictable pattern of the lunar cycle?

Why does the illumination of the Moon’s surface appear to change when viewed from Earth even though the Sun continuously illuminates half of the Moon?

What causes a solar eclipse?

What causes a lunar eclipse?

Would you describe the seasonal pattern on Earth as cyclical or occasional?

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STEMscopedia: POSITIONS OF THE EARTH,

MOON, AND SUN 6E2ABC

Reflect If you look up at the sky on most nights, you’ll see the Moon. You may have noticed that sometimes the Moon looks like a circle. Other times it looks like a half circle. On some nights, you can’t see it at all. Even though it looks different, the Moon does not really change. It looks like it changes because it orbits Earth. The Moon orbits Earth, while Earth orbits the Sun. The different shapes we see of the Moon occur because we see different amounts of its sunlit side. orbit: to travel in a repeating path How do the Moon and Earth move through space? around an object Both the Moon and Earth are nearly spherical bodies composed primarily of metals, like iron and rock. Unlike the Moon, Earth is a planet. A planet is a large, nearly sphere-shaped object that orbits a star. Earth isn’t exactly spherical primarily because it is rotating or spinning on an axis between its north and south poles. As it rotates, it forces the equator to bulge outward compared to the poles. Earth orbits one star, the Sun. The Moon is a satellite, which is a natural object that orbits a larger body. The Moon orbits Earth about once every 28 days. That is about one month. Earth’s orbit around the Sun is much longer than the Moon’s orbit around Earth. It takes about one year for Earth to orbit the Sun.

Earth orbits the Sun as the Moon orbits Earth.

Look Out The Moon appears to rise in the east and set in the west during different times of the day or night. It can be seen as often during the day as during the night! Due to the changing angle between the Sun, Moon, and Earth, different amounts of the Moon’s sunlit side face Earth in a cycle called the lunar phases. How can we use models to represent the orbits of Earth and the Moon?

As the Moon orbits Earth, the shape of the Moon looks Understanding the size comparison of the Sun, Earth, and the Moon different to us. We can see will help you understand their movements. different parts of the lit half of the Moon. Because of their greatly different sizes, it is very hard to compare the sizes of Earth, the Sun, and the Moon together. Earth is much bigger than the Moon. About 50 Moons could fit inside Earth. The Sun is even larger. About one million Earths could fit inside the Sun.

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STEMscopedia: POSITIONS OF THE EARTH,

MOON, AND SUN

To make a good model, you need to choose objects that either show size and location or objects useful for showing their movements. Now you need to consider distance. Even though your distances will not be exact, your model will still help show the patterns of how these objects move. The Moon revolves around Earth at a distance of about 30 Earth diameters. The Moon is about one-quarter the diameter of Earth. Knowing those two dimensions should help you create a scale model inside the classroom.

Try Now Try making your own model. 1. Gather materials that you can use to make a model of the Sun, Earth, and the Moon. Consider the following ideas or come up with your own. • Foam balls • Sports balls • Clay • A lamp • Food (marshmallows, candies, etc.) • Balloons 2. Arrange the objects to represent the Sun, Earth, and the Moon. 3. Show how the objects move. Describe the model in words.

What Do You Think? This picture shows a model a student made of the Sun (yellow balloon), Earth (white ball on golf tee sticking through the hole in the ruler), and the Moon (white ball at the end of the straw attached to Earth). What are some features of the model that make it useful? What are some limitations of the model? Solar and Lunar Eclipses Sometimes, the Moon blocks sunlight and its shadow falls on Earth. Other times, Earth’s shadow falls on the Moon. For example, some ancient people thought an eclipse of the Sun represented a mythical character taking bites out of the Sun. Actually, eclipses are simply caused by one celestial body casting a shadow on another celestial body. The Moon blocking the Sun casts a shadow on a small path on Earth, which people see as a solar eclipse. When Earth’s shadow falls on the Moon, people see a lunar eclipse.

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STEMscopedia: POSITIONS OF THE EARTH, MOON, AND SUN The Sun’s Apparent Path in the Sky Earth’s rotation causes the illusion that the Sun rises in the east, moves in an arc across the sky, and sets in the west. The angle of the Sun’s apparent path as it rises and sets depends on the observer’s latitude. Its height in the sky at any time of the day depends on the season. Those living at middle latitudes see the Sun follows different paths across the sky as shown in the top left diagram below. The violet path shows the Sun’s motion during the summer. The blue path shows the Sun’s motion during the fall and spring. The red path shows the Sun’s motion during the winter. At the equator, the Sun rises straight up, goes highest in the sky, and sets straight down. This is shown in the top right figure below. In polar regions, the Sun appears to move in a horizontal circle during summer since it stays up for months at a time. This is why these regions are sometimes called the “land of the midnight Sun.” During fall and spring, the Sun circles near the horizon. During the winter, the Sun circles below the horizon, which results in months of darkness. This is summarized in the bottom figure below.

Try Now Constellations move across the sky. Just as Earth’s rotation gives us the illusion that the Sun moves across the daytime sky, its rotation also gives us the illusion that the nighttime stars move across the sky. The stars move in recognizable patterns called constellations, rising in the east and setting like the Sun in the west. Constellations also follow a pattern. As Earth rotates, they appear to move from east to west across the sky like the Sun. You will need a clear night with no light pollution to spot the Big Dipper (Ursa Major) constellation. Face north and look for a large ladle in the sky. Compare the position of the dipper’s handle with the time of night. Also, because Earth revolves around the Sun, we are pointed to a different direction in space with each season. This journey around the Sun also causes the constellations to change in a regular pattern with the season. The observer’s latitude affects which constellations are visible as well. Star charts are available on the Internet that specify the latitudes for which each chart is applicable.

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STEMscopedia: POSITIONS OF THE EARTH,

MOON, AND SUN

Climate is affected by the angle of the Sun’s rays. The angle that the Sun’s rays strike Earth changes with latitude. At the equator, the Sun’s rays are most direct, resulting in hot, tropical climates. The angle of rays becomes more shallow toward the poles. There, slanted rays spread out the heat, causing colder climate conditions.

What Do You Know? Write the letter of the explanation that best matches each observation of the day or night sky. ____Climate changes with latitude. ____The Sun appears to rise in the east and set in the west. ____The stars appear to rise in the east and set in the west. ____The Moon follows a pattern of changing monthly appearances. ____A solar eclipse occurs. ____ A lunar eclipse occurs. ____Day and night. ____Change in seasonal constellations. ____One year. ____24 hours. A. The Moon blocks the Sun. B. Earth rotates on its axis. C. Earth revolves around the Sun. D. Earth blocks the Sun. E. The angle between Earth, the Moon, and the Sun changes as the Moon orbits Earth. F. The angle of the Sun’s rays changes from direct to slanted from the equator to the poles.

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STEMscopedia: POSITIONS OF THE EARTH, MOON, AND SUN Seasons If Earth’s axis was not tilted, we would not experience different seasons. However, Earth’s axis is tilted at a 23.5 degree angle. As Earth revolves around the Sun, sometimes the northern hemisphere is tilted toward the Sun. When the northern hemisphere is tilted toward the Sun, it receives more direct rays of sunlight. It is summer. In summer, days are longer and weather is warmer in the northern hemisphere. Plants there have plenty of sunlight for photosynthesis, and animals have plenty to eat. At the same time, the southern hemisphere is tilted away from the Sun and receives fewer direct rays of sunlight. As a result, days are shorter and weather is cooler in the southern hemisphere. It is winter. Plants there grow less actively and many lose their leaves. Animals are also less active. Some animals hibernate, or sleep through the winter. When the northern hemisphere is tilted toward the Sun, it receives more direct rays of sunlight than the southern hemisphere. During this time, the northern hemisphere experiences summer and the southern hemisphere experiences winter.

Seasons are more noticeable in places that are farther from the equator, the imaginary line around the horizontal center of the planet. No matter where Earth is along its orbit, the equator is never tilted away from the Sun. It receives direct rays of sunlight year-round. This is why climates are generally warmer near the equator. While there is some variation, temperatures near the equator stay relatively constant from month to month. You can see how Earth’s orbit is elliptical in this diagram. As Earth revolves around the Sun, the planet’s tilted axis causes the seasons. When the northern hemisphere is tilted away from the Sun, it experiences winter. As the planet moves to the opposite end of its orbit, the northern hemisphere passes through spring into summer. During summer, the northern hemisphere is tilted toward the Sun. It then passes through autumn (or fall), making its way back to winter. Remember, the northern hemisphere and the southern hemisphere are opposites. When the northern hemisphere is experiencing summer in the diagram above, the southern hemisphere is experiencing the opposite season, which is winter.

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STEMscopedia: POSITIONS OF THE EARTH,

MOON, AND SUN

Look Out Looking to the Future: Changes in Earth’s Tilt Although Earth’s axis is currently tilted at 23.5 degrees, this angle is not always constant. Earth wobbles slightly over time as it revolves around the Sun. This wobble causes the angle of Earth’s tilted axis to shift between 22 degrees and 25 degrees. This does not happen fast enough to be noticed on a human time scale. Rather, the shift between 22 degrees and 25 degrees takes about 41,000 years. This process is called a Milankovitch cycle, named after the astronomer who theorized that changes in Earth’s tilted axis affect the seasons. According to Milankovitch’s theory, there is a greater difference between summer and winter when Earth’s title increases. A strong winter can lead to significant buildup of ice at the poles. This ice can reflect the Sun’s radiation, blocking it from warming Earth’s surface. This can cause temperatures to drop even more. Eventually, this can lead to an ice age. When Earth’s tilt decreases, the seasons become milder. It is important to realize that many factors contribute to climate on Earth. Although Milankovitch cycles likely play a role in climate change, scientists do not think their effects will be strong enough to produce a new ice age during the next 50,000 to 100,000 years, and possibly longer.

Connecting With Your Child A Living Model Work with your child to model the motions of Earth and the Moon. Invite another family member to join you, if possible. You won’t need to gather any materials in advance because you will be the materials for this activity! 1. Choose an open space in a room inside your home or outside. Clear any objects or furniture from the space. The space does not have to be huge, but it should be large enough so you can walk in a circle without bumping into anything or tripping. 2. Choose who will represent Earth and who will represent the Moon. Set up a lamp as the Sun in the center of the area, unless you have a family member available who can represent the Sun. 3. Whoever is Earth should stand in position in orbit around the Sun. 4. Whoever is the Moon should stand in position in orbit around Earth. 5. When everyone is in position, slowly model the motions of Earth and the Moon. Be careful not to move too quickly. You have probably seen models of the solar system made from foam balls or even candies. In this activity, you and your child are the model. The goal of this model is to represent the orbits of Earth and the Moon. To create a good representation, you should use something or someone to represent the Sun. The Sun is the star at the center of the solar system. The planets and everything in the solar system travel around the Sun, so the Sun will stay in one place in the center of your model.

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STEMscopedia: POSITIONS OF THE EARTH, MOON, AND SUN Earth travels around the Sun. To travel around another object is to orbit it, and the path traveled is also called an orbit. The person acting as Earth will have to walk slowly around the Sun. Earth orbits in a counterclockwise direction, so the person should walk that way as well. In real life, it takes Earth one year to complete this motion. The shape of Earth’s orbit is actually an ellipse, which is like a circle that has been stretched. For the purpose of the model, you can consider the orbit to be a circle. As Earth orbits the Sun, the Moon orbits Earth. The person acting as the Moon should walk slowly around the person acting as Earth. As with Earth, the Moon moves in a counterclockwise direction. The Moon takes about 28 days to complete one orbit, so the person acting as the Moon should walk a little faster than the person acting as Earth. Everyone should be careful as they walk so as not to trip over one another. Try to make one complete orbit for Earth. The Moon should make about 12 orbits around Earth in this time. Questions to discuss with your child: • How did we model the orbits of Earth and the Moon? • How are the orbits of Earth and the Moon alike? How are they different? • About how many orbits does the Moon complete during one complete orbit of Earth around the Sun? In what ways was the model a good way to represent the orbits? • What are some things we could do to improve our model? • What are some limitations of any kind of model used to represent objects in space?

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6E2ABC Positions of the Earth, Moon, and Sun

Reading Science Name:

Date:

Group:

The Lunar Cycle 1 Rising into the inky, black sky, a giant yellow Moon casts an eerie glow over sleeping Earth. Although it is not producing its own light, the bright Moon illuminates the darkness by reflecting the Sun’s light to Earth, much like a mirror would do. Gazing at this round object during a night like this, you may notice that you can see the entire face. Known as a full moon, this is just one of the eight phases of the Moon. 2 Have you ever noticed that the shape of the Moon seems to always be changing? One night, the Moon may appear like the one described above, round and full. On another night, the Moon may present itself in the shape of a clipped toenail, or a crescent moon. Sometimes there might not be a Moon visible at all. What is happening? The explanation may surprise you. The Moon, like many things on Earth, has a cycle. Think of this cycle as a continuous circle that repeats itself over and over again. Taking almost 28 days to complete its orbital path, the Moon revolves around Earth. 3 As the Moon revolves around Earth, its position relative to the Sun changes. Think back to how the Moon is not producing its own light, but it is reflecting the light of the Sun. So, why from Earth’s surface do we sometimes see a full moon and sometimes see only a portion of the illuminated moon? The following is an explanation of what is actually going on. 4 When a light shines on a sphere, half of the sphere receives light, and the other half does not. This occurs because light rays travel in a straight line, so they do not bend around to strike the back side of the sphere. The back half of the sphere remains dark, in the shadow of the front half of the sphere. Try a little experiment to demonstrate this. Shine a bright flashlight on a golf ball or small orange. You should see a distinct line between the illuminated side and the shadowed side. Now try moving around to see different viewpoints of your “Sun-Moon” model. Think about how this change in viewpoint might explain why you also see varying illuminated portions, or phases, of the Moon.

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Reading Science Continued 5

The first phase of the Moon’s cycle is called a new moon. During a new moon, the Sun’s light is not shining on the side of the Moon that is facing Earth. From Earth, you only see the shadowed side of the Moon. When this happens, it appears as if there is no Moon present in the sky at all. As the Moon continues to travel around Earth, it now seems to be growing. Lighting up like a sliver of a clipped toenail on its right side, the Moon enters its second phase, called a waxing crescent. Waxing means that the amount of the illuminated Moon’s surface seen from Earth is increasing. Keep in mind that the amount of surface being illuminated is not changing. Only Earth’s point of view changes, similar to the kind of change you were able to see by moving to a different position with your “Sun-Moon” model using the golf ball or orange.

A first quarter moon is the next phase. In this phase, the right half of the Moon is illuminated by the Sun. Continuing into its next phase, the Moon is classified as a waxing gibbous moon. Almost all of the Moon can be seen in the night sky during this phase.

At this point in the cycle, we have traveled more than halfway through the Moon’s phases. After the Moon hits the full moon phase, it appears to start shrinking. During these phases, the term “waning” is used, meaning that the portion of illuminated moon surface visible from Earth decreases with each passing phase. In the waning gibbous moon phase, almost all of the surface is visible. Then comes the last quarter moon phase, with exactly half of the left lunar face being visible. This phase is followed by a waning crescent, and then we are back to a new moon, bringing us full circle. The Moon has completed its revolution around Earth.

As you gaze up into the night sky, the Moon might not seem so mysterious any more. The changing shapes are not really changing at all. Through its revolution around Earth, the Moon appears to magically grow or shrink because of the reflected light that we are able to view. These eight phases continuously repeat to complete the lunar cycle.

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6E2ABC Positions of the Earth, Moon, and Sun

Reading Science 1.

Which statement best shows why the Moon seems to be producing light? A

The Moon is making its own light.

The Moon is reflecting light from Earth.

The Moon is reflecting light from the Sun.

The Moon goes through eight phases.

Why does the Moon seem to change shape? A

As the Moon revolves around Earth, different parts are lit by the Sun.

The viewpoint from Earth of the illuminated side of the Moon changes.

Earth’s shadow is blocking light from the Sun.

The way the Moon produces light changes, so we see different shapes.

As used in this passage, what does illuminated mean? A

To be observed

To glow with light from within

To have light from some source shine on an object

To change in a regular pattern

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Reading Science

In the diagram, which moon phase is marked with the X? A

First quarter

Waning crescent

Waning gibbous

Waxing gibbous

What is the main point of the passage? A

The changing shapes of the Moon are not really changing at all.

The Moon is the only satellite revolving around Earth.

The Moon is difficult to travel to because of the changing tilt.

The phases of the Moon are difficult to predict and understand.

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6E2ABC Positions of the Earth, Moon, and Sun

Math Connections Name:

Date:

Group:

Part I: Moon Phases The diagram below shows the position of the Sun, the Moon, and Earth at different phases during Earth’s revolution around the Sun.

First Quarter Waxing Gibbous

New Full

Earth

Sunlight

Waxing Crescent

Waning Crescent

Waning Gibbous Third Quarter

What is the ratio of full moons to the total number of moon phases?

What is the ratio of gibbous moons to non-gibbous moon phases?

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Math Connections 3.

A synodic period is the time it takes for the Moon to move to the same period as seen by an observer on Earth. The Moon’s synodic period is about 29.5 days. How many first- and thirdquarter moons should you see in 6 synodic periods?

What is the ratio of days in one synodic period per quarter?

What is the ratio of days in a year to days in a synodic period? What is the unit rate? What does this number represent? Why do you think this is not a whole number?

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6E2ABC Positions of the Earth, Moon, and Sun

Writing Science Name:

Date:

Group:

LOOK

THINK Think about the relative positions of the Sun, Earth, and Moon. WRITE Explain why moon phases occur, and describe what happens during solar and lunar eclipses. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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Writing Science

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6th Grade Earth and Space Science

6E3AC

Water on Earth

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6E3AC Water on Earth

Student Handout

Name:

Date:

Potato Percentages Activity Create a pie chart showing the percentage of total mass that water represents on Earth. Label your chart.

Describe your thoughts regarding Earth’s water supply.

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6E3AC Water on Earth

Student Journal Name:

Date:

Group:

Part I: Where is the Water? Create a pie graph that represents Earth’s fresh water. Label the graph. Title:

Where is the largest supply of freshwater? Are we able to use the freshwater that is frozen in the glaciers? Which source of freshwater is easiest for us to access?

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STEMscopedia: WATER ON EARTH 6E3AC Reflect Have you ever wondered from where your next drink of water will come? Most likely you have never thought about it. It is easy to grab a glass and fill it up at the sink or the refrigerator. Drinking fountains are found in almost every hallway of your school, and taking a shower is probably a daily task for you. Parts of our world are not as fortunate. For example, South Africa is an area of the world that is facing a water shortage crisis due to climate change and weather patterns, specifically El Niño. A shortage of freshwater can potentially lead to serious diseases and economic problems. Seventy percent of Earth’s surface is covered in water. With that much water available, it seems that no one should be facing a shortage! However, the large majority of water on Earth is non-potable. Look at the different sources that make up Earth’s water supply. Freshwater Although 3% of Earth’s water is freshwater, a large percentage of that water is actually unusable also. Study the graphs above more carefully. What do you notice about the freshwater portion of Earth’s water supply? Ice Almost 69% of freshwater on Earth is stored in the form of ice caps and glaciers. The continent of Antarctica and the island of Greenland are large land areas almost completely covered with ice. Water locked up in glaciers and ice caps cannot be utilized by humans as a drinking water supply, but that water still plays an important role in the scientific world. Scientists monitor climate change and its effects on our world by observing how global warming impacts these large areas of ice. Groundwater Thirty percent of the freshwater on Earth exists as groundwater. Groundwater is any water that lies underneath the surface of the land. Groundwater is essential to life on Earth and is a vital component of the hydrologic cycle. A great portion of precipitation that falls to Earth seeps into the soil, percolates down through porous rock, and collects in aquifers. Aquifers are used as sources of drinking water for people and animals. Farmers utilize aquifers for irrigation of crops. However, realistically, aquifers should be considered nonrenewable resources. When people remove water from an aquifer, nature may require 300 to 1,000 years to replenish the supply. Although most people think of groundwater as water that infiltrates soil and permeable rocks to collect in large aquifers, groundwater also includes permafrost, soil moisture, and geothermal moisture.

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STEMscopedia: WATER ON EARTH Surface Water The tiny remaining 0.3% of Earth’s freshwater is surface water. Surface water is any water on top of the land. Most of this water is in the form of lakes, rivers, and marshes. Lakes are bodies of water that are completely surrounded by land and not connected to an ocean. Most lakes have rivers connected to them that allow water to move in and out. Rivers are natural, flowing sources of water. Rivers move from higher elevations to lower elevations. Smaller rivers act as tributaries to larger rivers, and most sizeable rivers eventually empty into larger bodies of water like oceans or lakes. Smaller rivers may be called brooks, creeks, or streams. Marshes, or wetlands, are shallow areas where land and water meet. A wetland must be flooded the majority of the time to provide a habitat for unique organisms. Marshes filter, clean, and store water. Wetlands are vital ecosystems because they hold floodwaters and help prevent erosion during times of flooding. Salt Water Ninety-seven percent of Earth’s water is salt water. Most of Earth’s salt water is found in its oceans, all of which are connected and cover approximately 70% of Earth’s surface. Some salt water exists in the form of saltwater lakes, such as the Great Salt Lake in Utah and many lakes in China. Despite the fact that oceans cover about 70% of Earth’s surface, people know very little about the topography under the surface of the water. Ocean topography is the study of landforms on the ocean floor.

What Do You Think? Because 97% of Earth’s water is salt water and non-potable, people throughout history have attempted to find methods to rid ocean water of its salt and other minerals to make it drinkable for people and animals. Scientists call this process desalination. Look at the example below of machinery used for the desalination of water and then answer the questions about it. Questions: 1. Based on what you know about the evaporation of seawater, how do you think desalination works? 2. What are some benefits of building desalination plants like the one in the picture? 3. What are some drawbacks of building desalination plants like the one in the picture? 4. What are some behaviors we can encourage to better utilize the supply of freshwater on Earth?

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STEMscopedia: WATER ON EARTH Ocean Topography Plate Tectonics The shape of the ocean floor is largely a result of a process called plate tectonics. The outer rocky layer of Earth is divided into seven large and many smaller sections called tectonic plates. The plates are arranged like a spherical jigsaw puzzle floating on top of Earth’s hot flowing mantle. Convection currents in the molten mantle layer cause the plates to move slowly about the Earth a few centimeters each year. Many of the geographical features on the ocean floor are a result of the interactions that occur at the edges of these plates where they move over or under each other, pull apart, or push together. The resulting ocean floor structures include continental shelves and slopes, canyons, oceanic ridges, trenches, island mountains, fracture zones, abyssal hills, abyssal plains, volcanoes, and seamounts. Underwater Trenches, Island Arcs, and Mid-Ocean Ridges Shifting tectonic plates may collide (converge), move away (diverge), or slide past (transform) each other. As plates converge, one plate may submerge under another plate, triggering earthquakes, building volcanoes and/or island arcs (like the Aleutian Islands of Alaska), or creating deep ocean trenches (such as the Mariana Trench in the Pacific Ocean). Where the plates are pulled away (diverge) from each other, molten magma flows upward between the plates, forming underwater mountain ranges called mid-ocean ridges, underwater volcanoes, hydrothermal vents, and new ocean floor crust. The Mid-Atlantic Ridge is an example of this type of plate boundary.

Look Out Two Common Misconceptions • Many people mistakenly think the deepest part of the ocean is in the middle. In reality, ocean trenches are the deepest features of the ocean. They form at converging plate boundaries, not in the middle of oceans. • People also incorrectly think that the ocean floor is flat. The ocean has many of the same features as are found on land. They contain underwater plains, canyons, seamounts (isolated underwater volcanoes), mountains, and mountain ranges (mid-ocean ridges). Most ocean floor features are larger than the corresponding features on land. The Continental Margin The ocean floor is a vast area comprised of hills, mountains, and valleys—all covered with water. Ocean floor topography starts with the continental margin, made up of the continental shelf, the continental slope, and the continental rise.

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STEMscopedia: WATER ON EARTH The outer continental shelf starts right off the coast as the water begins. This zone holds shallow water that does not exceed a depth of 150 meters. The shelf slopes gradually. The width of the continental shelf varies significantly, depending upon the locality. It can range from a few kilometers to hundreds of kilometers. Continental shelves often contain barrier islands, which are low islands parallel to the shore, or banks, which are low flat regions close to the surface of the ocean. Where the continental shelf stops, the continental slope begins. The ocean floor descends steeply. The steep inclines of the continental slopes identify the border between the thick granite of the continental crust and the thinner basalt of the oceanic crust. The continental rise is constructed of sediments that have washed down from the continental shelf and then the continental slope. The continental margin along the Atlantic Ocean has virtually no plate boundary activity. However, along the Pacific coast, the continental margin experiences a tremendous amount of tectonic activity, resulting in numerous volcanoes and earthquakes. The Ocean Basin Floor The next major feature of ocean topography is the ocean basin floor. It includes the abyssal plains. Abyssal plains are flat because any features they once exhibited are blanketed with a thick layer of sediment. Seamounts are another feature of the deep ocean floor. They are single, steep mountains that start as volcanoes over hot spots on the ocean floor. Some break the surface of the water and some remain completely submerged. Mid-ocean ridges are located where tectonic plates are separating. New ocean crust is created as magma flows into the gap between the tectonic plates. The underwater ridges are large mountain ranges. Deep ocean trenches are the deepest parts of the ocean. They occur at the site of converging tectonic plates, where one plate is being subducted under another plate. The Mariana Trench is the deepest part of the world’s oceans. It is located in the western Pacific Ocean, east of the Mariana Islands. The trench is about 2,550 kilometers (1,580 miles) long and has an average width of about 69 kilometers (43 miles).

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STEMscopedia: WATER ON EARTH What Do You Know? Matching Ocean Topography Terms and Definitions Abyssal plains

A. A mountain range at a divergent tectonic plate boundary located along the floor of the Atlantic Ocean, formed by plate tectonics, typically having a valley known as a rift running along its axis.

Continental shelf

B. Large geologic basins that are below sea level.

Mid-Atlantic Ridge

C. Long, narrow, deep canyons on the seafloor; they are also the deepest parts of the ocean floor formed where one tectonic plate moves under another.

Oceanic basin

D. A single volcanic mountain rising from the ocean seafloor that does not reach to the water’s surface (sea level), and is thus not an island.

Oceanic trenches

E. Flat or very gently sloping areas of the deep ocean basin floor.

Seamount

F. The extended perimeter of each continent and associated coastal plain, which is covered by relatively shallow seas and gulfs.

Continental slope

G. The abrupt steep change between the continental shelf and the ocean basin floor.

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STEMscopedia: WATER ON EARTH Connecting With Your Child To better help your child understand the topography of the ocean floor, create a model of the ocean floor together. Materials: • Shoe box with a lid • Modeling clay or Play-Doh™ • Piece of dowel about 25 cm long • Ruler with centimeter units • Pencil • Scissors • Graph paper Procedure: 1. Study the STEMscopedia thoroughly and know the following terms: continental shelf, continental slope, continental rise, basin, trench, seamount, and mid-ocean ridge. 2. Sketch a quick plan of a side view of an ocean floor. Be sure to include the edge of a continent, a continental shelf, a continental slope, a continental rise, a basin, a trench, and a mid-ocean ridge. 3. Create the ocean floor shapes in your shoe box with the modeling clay or Play-Doh™. 4. Next, punch eight evenly spaced holes down the center of the shoebox lid. 5. Put the lid on the shoe box, thus hiding the ocean floor from view. 6. Using graph paper, create a graph with the numbers 1-8 (for the number of holes) along the bottom (x-axis) and the numbers 1-25 (for the number of centimeters) up the side (y-axis). 7. Put the dowel into hole number one until it hits “bottom” (for example, the top of a mid-ocean ridge or the bottom of a trench). Record the measurement in centimeters on the graph with a simple dot. Repeat the process for holes 2-8. 8. When all the holes have been measured and recorded, join the dots in order using a ruler. When this is done, turn the graph upside down and label the parts of the ocean floor appropriately. You should see a representation of the floor you created in the shoe box on the graph paper.

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6E3AC Water on Earth

Reading Science Name:

Date:

Group:

The Ocean Conveyor Belt 1

Water in the ocean is always moving. Waves break the surface. Currents move in the shallows and in the depths. Currents near the surface are mainly caused by the winds and tides. Deep water currents run on a different engine.

Currents run through all of the Earth’s oceans. They are important for several reasons. The currents help keep global temperatures even. They move energy around the oceans. Otherwise, the equator and tropics would get too hot. The poles would get too cold. While deep water currents do play a part in energy transfer, this is mainly done by surface currents. These are currents in the top 100 meters of the ocean. Their main driving force is the wind. They flow quickly and form giant circles. One example is the Antarctic Circumpolar Current, which forms a giant ring around the continent of Antarctica.

Currents also cycle nutrients through the ocean. Water near the surface is rich in oxygen. Deep waters are rich in nutrients. When sea creatures die, they sink to the ocean bed. They decay and release nutrients into the deep water. There must be a way to mix and exchange the two. In fact, there is—a slow global deep water current. Wallace Broecker is a noted oceanographer. Broecker named this the ocean conveyor belt.

Deep ocean currents are caused by thermohaline circulation. What does this mean? Well, “thermo-” means temperature. And “-haline” means salt. But how do temperature and salt cause currents? The linking factor is density.

Density is a physical property of all materials. It is the measure of how much mass the material has for a standard particular volume, generally 1 cm3. Whether something sinks or floats on a liquid is based on its density. A more dense substance, either liquid or solid, will sink to the bottom. A less dense substance will be found on the top. Water is more dense as a liquid than as a solid. This is why ice floats. Liquid water can vary in density. As long as it remains a liquid, water gets more dense as it gets colder. Also, water’s properties change based on how much salt is dissolved in it. The measure of salt in a water sample is called salinity. Water gets more dense as its salinity goes up.

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Reading Science Continued 6 There are three special places on Earth where conditions are right to pump the ocean conveyor belt. Two are in the North Atlantic Ocean. The other is the Weddell Sea off the coast of Antarctica. All three locations lie near either the north or south Arctic Circle. On the map at the top of this passage, these locations are labeled “deep water formation.” Conditions are right in these places to make water very, very dense. It will sink to the bottom of the ocean. But how does this happen? We will focus on the Weddell Sea for the answer. Remember that a similar process happens in the North Atlantic to form deep water. 7

During the winter months, air temperatures in Antarctica are very cold. Areas surrounding Antarctica get very little sunlight for much of the winter. Moving closer to the South Pole, some areas get no sunlight at all for weeks. Very cold winds from the interior of the Antarctic continent blow away from the South Pole. At the Weddell Sea, local geography funnels these winds over the surface of the water. The Weddell Sea is fringed year round by ice sheets. Conditions are much colder in the winter. Sheets of ice form rapidly. Much of the sea has seasonal ice coverage. This rapid ice formation is one piece of the puzzle. The strong icy winds are another.

When ice forms from salt water, an interesting thing happens. The ice that forms is pure water. The salt gets left behind. (This works as long as some of the water remains liquid.) In the Weddell Sea, there is rapid formation of lots of pack ice. Much of the salt is left behind. This leads to water with very high salinity. There is another interesting property of water. As the salinity of a water sample goes up, its freezing point goes down. This means that very salty water will stay liquid below the freezing point of fresh water. The icy winds cool the water, often to −1°C (30°F). The winds turn this high salinity water into the coldest, densest water in Earth’s oceans. It sinks. This forms the Antarctic Bottom Water. The other two locations form slightly less dense North Atlantic Deep Water.

The sinking of the newly formed deep water pushes the water from previous years. This drives the slowly moving ocean conveyor belt. The Antarctic Bottom Water forms a current that travels around the continent of Antarctica. The North Atlantic Deep Water slowly creeps south to join these currents. Portions of the giant current break off. They travel along the bottom of the Indian and the Pacific Oceans. The deep currents are shown in blue in the image at the top of this passage. Finally, they will return to the surface. These upwellings bring nutrients up to replenish surface water. Scientists think deep water may take between 600 and 1,000 years to return to the surface.

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6E3AC Water on Earth

Reading Science 1.

What is the driving force of the deep water ocean conveyor belt? A

Winds push the deep water into the Pacific and Indian Oceans.

Gravity from the Moon pulls the deep water toward the equator.

The spinning of the Earth makes the deep water current run in circular paths.

Very cold temperatures create very dense water that pushes the deep current along.

What is the meaning of circumpolar in paragraph 2? A

Circular path around the pole

Wind-blown current

Cold and salty

Sinking

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Reading Science Examine the map below. Use it to answer questions 3 and 4.

A B C

D 3.

Based on the information in the passage, which location on the map above marks the Weddell Sea? A

Which location on the map above is a source of North Atlantic Deep Water? A

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Reading Science 5.

Which of these characteristics will produce the most dense water? A

High salinity, high temperature

High salinity, low temperature

Low salinity, high temperature

Low salinity, low temperature

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6E3AC Water on Earth

Math Connections Name:

Date:

Group:

The majority of Earth’s surface is covered with water. Most of Earth’s water is salt water. Only a small amount is fresh water, including water found in many lakes, rivers, and underground streams, brooks and basins, and in the form of ice. Earth has an estimated 338,168,194 cubic miles of water. However, not all of that water is drinkable. Use the following formula to figure out just how much water is available for the human population to drink: Percent of Water Type×Total Amount of Water=Amount of Water Type Water Source

Percent of Total Water

Oceans, seas, and bays

—

96.5

Ice caps, glaciers, and permanent snow

68.7

1.74

Ground water

—

1.69

Freshwater

30.1

0.76

Saline

—

0.93

Soil moisture

0.05

0.001

Ground ice and permafrost

0.86

0.022

Lakes

—

0.013

Fresh

0.26

0.007

Saline

—

0.006

Atmosphere

0.04

0.001

Swamp water

0.03

0.0008

Rivers

0.006

0.0002

Biological water

0.003

0.0001

Chart adapted from http://water.usgs.gov/edu/earthwherewater.html

Percent of Freshwater

How much of Earth’s total water is in oceans, seas, and bays?

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Math Connections 2.

In the column Percent of Total Water, the shaded cells represent the amount of freshwater on Earth. What is the total percent of freshwater on Earth?

The people on Earth can survive only on freshwater. Based on your answer in question 2, what is the total amount of freshwater on Earth?

While a lot of freshwater seems to be available to us, much of that water is frozen in ice or located underground. Most people survive on water available in lakes and rivers. What percent of Earth’s freshwater is located in rivers and lakes?

Create an equation to determine how much total freshwater is available to us in lakes and rivers. (Use your answers from questions 3 and 4 to help you.)

Solve your equation to figure out how much total water is available to us in Earth’s lakes and rivers.

What factors can affect the cleanliness of the water in lakes and rivers? How important is it for us to keep the water in lakes and rivers clean?

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6E3AC Water on Earth

Writing Science Name:

Date:

Group:

LOOK

THINK Think about the percentage of Earth that is covered in water. WRITE Describe where Earth’s water resources are and explain what they consist of. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E3AC Water on Earth

Writing Science

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6th Grade Earth and Space Science

6E3B

The Water Cycle

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6E3B The Water Cycle

Student Journal Name:

Date:

Group:

The Water Cycle Part I: Model of the Water Cycle Amount of water_____________ Amount of salt__________________ Location of bottle___________________________________________________ 1.

Predict the changes you will observe over the next few days with your salt water in the bottle.

What does the blue water represent? ______________________________

Observations Day One: Draw and label what you see.

Day Two: Draw and label what you see.

Day Three: Draw and label what you see.

After several days, bring the water cycle bottle back to your table. On the back of your Student Journal, draw and explain the changes you observed.

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STEMscopedia: THE WATER CYCLE 6E3B Reflect Go pour yourself a glass of water and look carefully at it. Where has it journeyed before it arrived in your glass? Imagine—water molecules in that glass of water could have rained on Pangaea, been gulped by a dinosaur, been frozen in a glacier during the Ice Age, fallen from a raging hurricane, snowed onto the North Pole, floated by Antarctica as an iceberg, flowed with piranhas in the Amazon River, flooded crops at the Nile River, or traveled with the Gulf Stream in the mighty Atlantic Ocean. How is this possible? The water on our planet has been around for billions of years and is continually recycled and purified. Where will the water you drink now travel in the future? What is the water cycle? Also known as the hydrologic cycle, it is a complex process that is activated and fueled by energy from the Sun. Exchanging immense amounts of energy, water is transferred between Earth’s surface and the atmosphere. Wind, weather, and gravity also play a role in the water cycle by keeping water in constant motion. Water covers more than 70% of Earth’s surface. It is the only substance on Earth that exists naturally in all three states of matter: solid ice, liquid water, or gaseous vapor. When water moves through the hydrologic cycle, it continually changes between the three states. Why is the water cycle important? Only about 1% of all water on Earth is available for biological consumption. The water cycle continuously recycles our limited supply of available freshwater. The water cycle is composed of six processes: evaporation, condensation, precipitation, infiltration, runoff, and transpiration. Evaporation is the process of a liquid gaining energy and entering the gaseous phase. During the water cycle, liquid water enters the atmosphere as water vapor. Oceans make up 97% of water on Earth. When water at the ocean’s surface is warmed by the Sun, it gains energy, changes into water vapor, and transfers into the air, completing the process of evaporation. During evaporation, only water molecules evaporate. Salt and other particles are left behind. You may notice this on a smaller scale when you sweat. When the sweat evaporates off your skin into the air, your skin feels and tastes salty. Sources of evaporation for the water cycle are large and small bodies of water (both freshwater and salt water), plants, and animals.

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STEMscopedia: THE WATER CYCLE Condensation is the reverse process of evaporation. Water in its gaseous state loses energy and is changed back into a liquid. Often it loses energy due to a loss of temperature. For example, have you ever gotten a glass of cold water to drink on a hot day? When the water vapor molecules in the warm air come into contact with the cold glass, they condense, causing the outside of the glass to be covered with drops of water. During the water cycle, water vapor in the atmosphere cools and condenses into tiny water droplets, which form clouds. Water droplets clump together to form drops of water, which will eventually become heavy enough to fall to Earth. Precipitation is the process of condensed water vapor in the atmosphere falling back to Earth. Precipitation occurs when temperature and atmospheric conditions are right and when drops become heavy enough that gravity pulls them down toward Earth. Precipitation can fall to Earth in the form of rain, snow, sleet, hail, or freezing rain. Infiltration is another process in the water cycle during which rainwater soaks into the ground through soil and rock layers. Water percolates through soil and certain rocks that are porous. Groundwater is defined as the water beneath Earth’s surface. Rainwater is often absorbed at the surface and percolates until it reaches an aquifer, an underground area that is filled with water. Groundwater can also include permafrost, soil moisture, and geothermal moisture. Generally, groundwater flows naturally to the surface at a spring or a wetland.

Runoff describes the process in the water cycle during which some rainwater does not percolate into the soil and instead flows over the land. Runoff occurs for a variety of reasons. Soil saturation, rapid rate of rainfall, and impermeable land surfaces are a few possible causes. As surface runoff flows over land, it often dissolves minerals and transports them as it runs downhill to rivers, lakes, or oceans.

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STEMscopedia: THE WATER CYCLE Transpiration is the process that describes the role plants play in the water cycle. Water from the soil is gathered by the roots, transported by the stem, and stored by the leaves. When the water reaches the leaves, some of the water evaporates into the air from the stomata, tiny pores on the leaves. This is transpiration.

Animals also contribute to the water cycle through respiration and perspiration. In this case, respiration refers to physiological respiration rather than cellular respiration. Physiological respiration focuses on the transport of oxygen to cells and the transport of carbon dioxide from cells. Physiological respiration supplies cells with the oxygen they need to conduct the process of cellular respiration. To simplify, when animals breathe, they use carbon dioxide and glucose to gain energy, and carbon dioxide and water are created as byproducts. When animals exhale water, it becomes water vapor, supplying the water cycle with another source of evaporated water. When people or animals perspire, sweat evaporates into the air and becomes part of the water cycle.

Look Out The Sun’s energy and the water cycle are connected to many of Earth’s other processes. Some of these processes include wind, waves, ocean currents, and tides. Winds are created by the Sun’s uneven heating of Earth. In turn, ocean waves are caused by winds blowing across the surface of the water. The friction between air molecules and water molecules causes energy to be transferred from the wind to the water. Wave appearance varies during different weather patterns, from smooth and slowly rolling to choppy, towering, and crashing.

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STEMscopedia: THE WATER CYCLE The wind and the Sun also work together to form currents. An ocean current is a continuous flow of water within the ocean. Wind causes water to move, which can aid in the creation of surface currents or deep ocean currents. Currents can also be influenced by temperature changes, salt content, and water density. Ocean currents have an effect on the water cycle. As currents move water from place to place, they can cause temperature changes that can affect the rate at which water both evaporates and condenses. Tides are another of Earth’s processes that are connected to the water cycle. Tides are the regular rise and fall of Earth’s water caused by the gravitational pull between the Sun and the Moon. Tides occur twice each lunar day. Tides change season to season based on Earth’s position in its revolution around the Sun. Weather in an area can also affect the level of water during high tide and low tide. Tides can affect the evaporation rates, further influencing the water cycle.

What Do You Think? Most water molecules on Earth are combined with other compounds, ions, or particles. Pure water is rare, but pretend you are a pure water molecule. You consist of two hydrogen atoms and one oxygen atom held strongly together by covalent bonds, unlikely to be split apart. Imagine you are traveling through the water cycle. Answer the following questions and then check at the end of the STEMscopedia to see the answers. You are floating on top of a lake when the Sun shines on you and—poof!—you evaporate into the air as water vapor. How long will you float in the air before you condense and fall back to Earth as precipitation? You fall onto soil and percolate into an aquifer. How long does your journey take before you are back to the surface and ready to evaporate once again? You finally rejoin the water cycle and evaporate once again. Then you fall back to Earth as a snowflake and eventually find yourself at the bottom of a huge glacier. How long could you be stuck in the glacier before you return to active movement through the hydrologic cycle?

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STEMscopedia: THE WATER CYCLE What Do You Know? The water cycle is a very complex process that is affected by many factors, including climate. When the climate is very cold, as it is during ice ages, more (and larger) glaciers and polar ice caps form. The water that is trapped in glaciers and ice caps lessen the amount of water that remains throughout the rest of the hydrologic cycle. Additionally, due to cold temperatures, a greater percentage of precipitation is frozen precipitation, which is not as readily available for many plants and animals. The opposite is also true. Many scientists concur that the average temperature on Earth is increasing. When global warming occurs, such as during present times, glaciers and polar ice caps melt. This causes more water to be available for the hydrologic cycle. In addition, rising temperatures result in an increase in evaporation. Increased evaporation, in turn, leads to a rise in condensation in the atmosphere. Scientists predict these conditions will lead to an increase in cloud cover, humidity, and precipitation. Precipitation of warmer climates tends to be rain, rather than snow, hail, or sleet. A surge in rain rates causes a greater danger of flooding in many areas. Surprisingly, scientists predict that despite increased amounts of rain, many areas of drought will intensify. Because water evaporates more quickly and more thoroughly in higher temperatures, and due to certain landforms and atmospheric conditions, droughts will become more severe. In fact, scientists forecast that regions currently experiencing environments of plentiful rain or harsh droughts will exhibit even more extreme conditions as global warming continues. The map below illustrates the precipitation forecast for approximately 50 years in the future. It depicts the changes in precipitation as compared to current times. Look carefully at the map and then answer the following questions. 1. What do you notice about the areas of heavy precipitation? 2. What do you notice about the areas of drought? 3. Why do you think global warming intensifies the extremes such as regions inundated by precipitation and zones suffering from drought? 4. How could the changes predicted by this map affect life on Earth, especially for plants, animals, and people?

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STEMscopedia: THE WATER CYCLE Connecting With Your Child The hydrologic cycle is a continuous cycle in the world around us. To help your child better understand the concept and processes of the water cycle, create a model of the water cycle together. Materials: You will need: • Large clear bowl • Small container (such as an 8-oz clear plastic cup) • Medium-sized rock • Clear plastic wrap • Large rubber band, stretchy headband, or string Procedure: • Place the clear plastic cup inside the bowl. • Fill the bowl with about 1 inch of room temperature water. Make sure you do NOT get any water inside the clear plastic cup! • Cover the bowl with the clear plastic wrap. • Fasten the plastic wrap tightly across the bowl using the rubber band, headband, or string. • Put the rock on top of the middle of the plastic wrap. • Put the water cycle apparatus by a window in the Sun. • Observe your water cycle contraption every few hours.

Here are some questions for you to discuss with your child: 1. What happens on the inside of the plastic wrap? 2. How long does it take for water to condense? 3. What do you notice about the inside of the clear plastic cup as time passes? 4. Why do you think it is important to put the apparatus in the Sun? 5. How does this model relate to the hydrologic cycle on Earth?

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6E3B The Water Cycle

Reading Science Name:

Date:

Group:

One Percent of Earth’s Water 1.

Have you ever looked outside on a rainy day and wondered where the rain came from? Where was that water a week or a year or a hundred million years ago? It could have been in the ocean by the Galapagos Islands, in a swimming pool in Florida, or frozen in the middle of a glacier during an ice age. Where will that water be tomorrow or next month or in a thousand years? It could be evaporating into a hurricane in the Atlantic Ocean, crashing onto a Hawaiian beach, or gusting past Mount Everest as a snowflake. Wherever it might be, it will still be here on Earth. Why? That drop of water is part of the water cycle.

What is the water cycle? The water cycle is a process that recycles and filters Earth’s water. The cycle moves water back and forth between land, water, and air over and over again. It is necessary because even though about 70 percent of Earth’s surface is covered by water, only about 1 percent of that water is available freshwater! The other 99 percent of Earth’s water is salt water, frozen water, groundwater, or water vapor. The 1 percent of Earth’s usable water has to meet the needs of many of Earth’s organisms. The water cycle makes that possible by recycling and purifying Earth’s existing water supply.

The water cycle consists of six main processes. Evaporation happens when liquid water gains energy and becomes water vapor. Condensation occurs when water vapor loses energy and turns into liquid water. Precipitation takes place when water in any liquid or solid form falls from the sky to the ground. Infiltration is when water soaks into the soil. It slowly flows through porous rock and moves underground. Runoff means precipitation that cannot be absorbed into the ground. Instead, it flows over the surface of the land.

Finally, transpiration is a biological process in which plants contribute to the water cycle. Plant roots take water from the soil, pass it up through stems, and store it in leaves. While water is in the leaves, some of it is released into the atmosphere as water vapor. Animals contribute to the water cycle through respiration and perspiration. When animals breathe, they inhale oxygen and use sugar from food to create usable energy. Then animals exhale carbon dioxide and water vapor. Perspiration contributes to the water cycle when animals sweat and the sweat evaporates.

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6E3B The Water Cycle

Reading Science 5.

How does the water cycle have enough energy to continuously cycle Earth’s water? The Sun is the energy source. The Sun causes evaporation. Evaporated water vapor eventually condenses, precipitates, and either infiltrates or runs off Earth’s surface. If water enters a plant’s roots or is consumed by an animal, it might experience transpiration, respiration, or perspiration. In addition, the Sun causes melting ice, winds, ocean currents, tides, and seasons. All of those factors affect the water cycle. The water cycle would not be possible without the Sun. And without the water cycle, life on Earth would not exist.

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6E3B The Water Cycle

Reading Science 1.

The purpose of this passage is to __________. A

encourage readers to conserve the limited supply of freshwater

explain how the water cycle works

explain the difference between transpiration and respiration

explain what the world would be like without the Sun

Which of the following is the best definition for cycle as used in this passage? A

A process that helps organisms survive on Earth

To ride a bike

Sequences of events that repeat themselves

Actions related to water that take place

Which of these sequences could NOT take place during the water cycle? A

evaporation --> condensation --> precipitation --> runoff

condensation --> precipitation --> runoff --> evaporation

precipitation --> infiltration --> transpiration

evaporation --> precipitation --> condensation --> runoff

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6E3B The Water Cycle

Reading Science 4.

Which statement might be used to convince scientists of the necessity of inventing a way to convert saltwater to freshwater? A

More than 70 percent of Earth’s surface is covered in water.

The water cycle continually recycles and purifies Earth’s water.

Even though Earth possesses a large supply of water, most of it is ocean water, and only 1 percent of it is available freshwater.

When water from the ocean evaporates, the salt remains behind and only water vapor enters the air.

Which statement is true of the processes involved in the water cycle? A

Water must precipitate before it can condense.

Evaporation only occurs when the sun is shining.

Transpiration, respiration, and infiltration are biological processes that are part of the water cycle.

The Sun provides the necessary energy for the water cycle.

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6E3B The Water Cycle

Math Connections Name:

Date:

Group:

Water evaporates from Earth’s surface, rises and cools, condenses into rain or snow, and falls again to Earth’s surface. The water falling on land collects in rivers and lakes, soil, and porous layers of rock, and much of it flows back into the oceans. The cycling of water in and out of the atmosphere is a significant aspect of Earth’s weather patterns. Earth’s Water Supply 1. Oceans circulate heat around Earth in the form of ocean currents, and 96.5% of Earth’s water supply is the salt water that makes up oceans, seas, and bays. Write an equation used to represent the total volume of saltwater in oceans, seas, and bays. Let (x) in your equation represent Earth’s total volume of water.

Earth’s total water supply is 326,000,000 cubic miles. Use the expression from question 1 to calculate the volume of Earth’s water supply in oceans, seas, and bays.

Evaporation/Condensation 3. Clouds form as water evaporates from the ocean. When clouds enlarge enough, rain falls from them. If the temperature is cold enough, they may emit snow. The water found in Earth’s atmosphere is 0.00095% of Earth’s total volume of water. Create and evaluate an equation to calculate the amount of water in Earth’s atmosphere. Let (x) in your equation represent Earth’s total volume of water.

Precipitation 4. A local gardener collects rainwater to water her garden in the hot summer months. She has 36 gallons of water left after the summer is over (August 31), and she needs a total of 612 gallons of water by May 1. Create and solve a number sentence to calculate the average number of gallons it needs to rain each month from September to April.

Each month, a flower gardener collects ¾ of the water he uses for irrigation from rain barrels and ¼ of his rain water from a neighbor. Write an equation to calculate the amount of water he collects from rain barrels (y), given the total amount of water he collects (x).

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6E3B The Water Cycle

Writing Science Name:

Date:

Group:

LOOK

THINK Water on Earth can be found as a solid, liquid, or gas. The Sun’s energy fuels atmospheric conditions that affect the cycling of such water in order to move it from place to place. Some of these processes include evaporation, condensation, precipitation, runoff, and transpiration. Consider how water found in a glacier can make its way into a glass of water that started from the energy of the Sun. WRITE Describe the process in which the Sun’s effect on the atmosphere leads to the cycling of water from a glacier to a glass of water. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E3B The Water Cycle

Writing Science

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6th Grade Earth and Space Science

6E3D

Waves, Currents, and Ties

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6E3D Waves, Currents, and Tides

Student Journal Name:

Date:

Group:

Part I: Motion of the Ocean 1.

Explain the cause and effect relationship between the waves and the bobber

What natural force generates surface ocean waves?

Draw a picture comparing the waves near the beach before and after you added the toy boat. Before (blowing gently through the straw)

After (blowing harder through the straw)

Explain the cause and effect relationship between the straw and the waves created in your model. ___________________________________________________________________

Explain the cause and effect relationship between the waves and the “beach” in your model.

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6E3D Waves, Currents, and Tides

Student Journal Part II: Deep Ocean Currents 1.

Complete the data table below once the demonstration is complete.

Initial salt water temperature: ________ Thermometer One

Thermometer Two

Thermometer Three

Before salt water is added After salt water is added Time in sec for thermometer reading to start dropping 2.

Write a description of the observed water movement.

Using the Teacher Reference Sheet: Deep Ocean Currents, answer the following questions. 3.

Deep ocean currents occur when sea ice melts. Why does the melting of sea ice cause currents to flow deep in the ocean instead of on the surface?

If the chilled saltwater mixture represents melting sea ice and the room temperature aquarium water represents the ocean, what does this model show about the formation of deep ocean currents?

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6E3D Waves, Currents, and Tides

Student Journal Part II: Deep Ocean Currents, continued 5.

Deep ocean currents are often called the conveyor belt of the ocean, redistributing cold ocean water and bringing rich nutrients from the deep ocean to the surface. Using red and blue map pencils, color in the warm and cold deep ocean current flow on the map below.

Using data and observations, write a scientific explanation describing how deep ocean currents redistribute thermal energy around the globe.

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6E3D Waves, Currents, and Tides

Student Journal Part III: Tidal Force 1.

Which parts of the model represent a high tide?

How many times do the continental lands on Earth rotate into a “high tide” each day?

How many times do the continental lands on Earth rotate into a “low tide” each day?

Times for daily high tides and low tides change by a few minutes each day for all coastal communities. What causes the time of daily tides to change as shown by your model?

A limitation of this model is that it looks as if the Moon holds water in place while the solid Earth spins on its axis. What is really happening?

The images below shows the same area during high tide (left) and low tide (right). What effect does the tide have on the land area?

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STEMscopedia: WAVES, CURRENTS, AND TIDES 6E3D Reflect Have you ever been to the beach and noticed the waves come up higher on shore than at other times? Have you been swimming in the ocean or in a lake and felt areas of the water that are noticeably colder or warmer? What makes ocean waves bigger on one day than on another? Water currents, waves, and tides are caused by different events and can impact Earth’s systems in many ways. Objects in space affect Earth’s systems. Throughout the day, water levels in oceans and lakes around the planet rise and fall. These regular movements, or tides, are made by the motions and positions of three objects in space. These objects are Earth, the Moon, and the Sun. Each day, Earth makes one rotation on its axis. (Earth’s axis is an imaginary line that runs through the planet’s center, between its north and south geographic poles.) The Moon revolves, or moves, around Earth. One revolution of the Moon around Earth takes about 28 days, or one month. Meanwhile, Earth revolves around the Sun. One revolution of Earth around the Sun takes about 365 days, or one year.

The Moon revolves around Earth as Earth revolves As they move through space, the Moon, Earth, and the Sun exert forces around the Sun. Although on one another. The force of gravity is affected by two variables: the the Sun is much larger than masses of the objects and the distance between them. Although the the Moon, the Moon is nearMoon is much less massive than the Sun, the Moon is much closer ly 400 times closer to Earth. to Earth than Earth is to the Sun. As a result, the force of the Moon’s (This diagram is not drawn gravity on Earth is more than double the force of the Sun’s gravity on to scale.) Earth. Substances that are free to move on Earth’s surface, such as ocean water, are more greatly affected by the Moon’s gravity than by the Sun’s. This is important for Earth’s tides. As the Moon revolves around Earth, it pulls water in oceans and lakes toward it. This causes water levels to rise in some places and to fall in others.

Look Out All things in the universe that have mass have gravity and pull on each other. We can see the effect of the Moon’s gravity as tides rise and fall. As the Moon’s gravity pulls on Earth, Earth pulls back on the Moon. If the Moon had any oceans or lakes, the water in those bodies would also experience tides. Gravity affects ocean tides. Each day, tides on Earth rise and fall between two extremes. A high tide is the highest point on a shore that water will reach, mainly due to the gravitational pull of the Moon. At any given time of day, high tides are produced on whichever shores are facing the position of the Moon relative to Earth. At the same time, high tides are also produced on the shores opposite the position of the Moon relative to Earth. In other words, at any given time on Earth, one tidal bulge faces the Moon, and one tidal bulge faces the opposite direction.

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STEMscopedia: WAVES, CURRENTS, AND TIDES What causes this second tidal bulge? A combination of gravity and inertia. Inertia is the tendency for something to remain at rest or in motion unless acted on by an unbalanced force. Water on Earth has inertia. It tends to stay in place unless acted on by an unbalanced force. For example, forces from winds cause waves as air moves across the surfaces of oceans and lakes. Another force that overcomes water’s inertia is gravity. Look at the diagram on the right. On the side of Earth facing the Moon, the pull of the Moon’s gravity is greater than the water’s inertia—that is, its tendency to stay in place. So the water on that shore bulges toward the Moon. At the same time, the Moon’s gravity pulls Earth slightly toward the Moon. The Moon’s gravity doesn’t affect water on the side of Earth opposite the Moon. Therefore, as the planet is pulled in one direction toward the Moon, the water on the opposite side of the planet remains in place. The result is a second tidal bulge due to inertia. As Earth rotates, the bulges move around the planet. However, they are always opposite each other.

The Moon’s gravity and the inertia of water create two high tides on opposite sides A low tide is the lowest point on a shore that water will reach. Low tides of Earth. Two low tides hapalways happen at places on Earth that are at right angles to the tidal pen at right angles to the bulges. Like high tides, two low tides occur at the same time on opposite tidal bulges. sides of Earth. At any given place on Earth, high tides occur twice most days and low tides occur twice most days. For example, suppose a beach in New Jersey faces the Moon at noon. That beach will experience a high tide at noon (as will a beach on the opposite side of the planet). Approximately 12 hours later, that beach will face away from the Moon. This will produce another high tide around midnight. Low tides on the same beach will occur at approximately 6:00 p.m. and 6:00 a.m.

Look Out Tides don’t occur at the same times every day. At any beach, high tides are separated by approximately 12 hours and 25 minutes. The same is true of low tides. Therefore, each day, high tides and low tides happen slightly later than they happened the previous day.

What Do You Think? Find Georgia’s Atlantic coast on a globe of Earth. (If you do not have a physical globe, you can find many globes online. Enter the term “virtual globe” in a search engine.) When it is high tide in Georgia, where on Earth is another place that is also experiencing a high tide? Where is it low tide? Choose one other location on another part of the globe. When it is high tide in this location, where on Earth is it also high tide? Where is it low tide?

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STEMscopedia: WAVES, CURRENTS, AND TIDES Density affects ocean currents. Liquids are affected by differences in density. When a liquid is less dense than another liquid, the less dense liquid floats in the denser liquid. For example, olive oil, vegetable oil, and mineral oil are all less dense than freshwater, so they all float on the water’s surface. You can try this at home by pouring one of these oils into a container of tap water. Warm water is less dense than cold water because warm water particles have more energy. As a result, warm water floats on cold water. The surfaces of Earth’s oceans are more exposed to winds than the deeper oceans. Wind can push the surface water, causing the water to flow and creating surface currents. The gravitational pull of the Moon also influences surface currents by driving the tides. Deeper ocean currents are driven by differential heating of sea water, which leads to convection cycles. The surface of the ocean is open to the sky, allowing it to absorb more solar radiation than the deeper oceans. This means surface water is typically warmer than deeper water. As the surface currents flow away from Earth’s equator toward colder regions, the water cools and sinks. When it reaches warmer depths, it rises again. The following diagram shows how deep ocean currents carry warmer and colder water throughout the Atlantic Ocean. What makes waves? Think about the times you have been to the beach or been swimming in a lake. Waves, whether large or small, are never-ending. How is this possible? Sometimes, waves have man-made causes, but in nature, there are other forces that cause waves. Read on to find out how waves form in the ocean. Waves form in different ways. When you see waves in the ocean, you are watching energy pass through the water, and that energy can have a variety of sources. Waves tend to be categorized by the way in which they form. The most common waves are surface waves and are caused by wind blowing along the surface of the water. Wind pushes the ocean water ahead of it and transfers potential energy to kinetic energy, causing the water to crest and “break” as it comes ashore. These are the waves you might see at the beach on a sunny day. Hazardous weather conditions and geological events create dangerous waves that can be quite destructive. Unlike surface waves, which gradually alter a coastline through weathering and erosion, waves from severe storms or earthquakes in the deep ocean basin create massive waves that destroy coastline and structures built there. Hurricanes, which vary in size and intensity, create a storm surge, which may seem insignificant in deep ocean waters, but its intensity increases as it moves into shallow water. Storm surge is water that travels several hundred miles from swirling hurricane winds and is pushed to shore when the storm reaches land. A surge from a hurricane, along with normal tides and waves, can increase water level 30 feet or more.

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STEMscopedia: WAVES, CURRENTS, AND TIDES Tsunamis are waves caused by deep ocean earthquakes, landslides, or other submarine instabilities. Like storm surges from hurricanes, the height of a tsunami in the deep ocean doesn’t dramatically increase until it reaches shore. Traveling across the ocean at up to 500 miles an hour, tsunamis can be up to 60 miles long and 100 feet high. Reaching as far inland at 1,000 feet, tsunamis can be strong enough to cause mass destruction.

Look Out For years, people thought tidal waves and tsunamis were one and the same. Unlike tsunamis, which form from geological events, tidal waves form as a result of gravitational forces between Earth, the Moon, and the Sun. Tidal waves lack the intensity and devastation of tsunamis.

What Do You Know? October 29, 2012, was a record-breaking day for weather forecasters and citizens living along the East Coast of the United States. Dubbed “Frankenstorm,” Hurricane Sandy was truly a monster storm that moved through the Caribbean and up the East Coast. It was considered an unusual event with high wind speed and flooding from a tidal surge and broke many records, including the largest Atlantic hurricane and highest New York City storm surge. Making conditions more extreme, the Moon was full as Sandy made landfall. How did the full moon contribute to Sandy’s devastating effects?

Connecting With Your Child Charting the Tides You can relate the discussion of tides to the phase and position of the Moon in the night sky. Find a tide table for a nearby location (or a distant location of your choice, if you do not live near an ocean or a large lake). You can find this information online or in some newspapers. Have your child review the data for several months, noting when high and low tides happen and how great or small the tidal range is each day. If your child has already learned about the lunar cycle and the Moon’s phases, you may combine your study of tides with observations of the Moon. Take your child outdoors in the evening, bringing a notebook of unlined paper and a pencil. Have your child sketch the Moon each night and identify its phase (e.g., new moon, waxing crescent, first quarter moon, etc.), then connect this information to what they have learned about tides. Here are some questions to discuss with your child: 1. How do tidal patterns relate to the positions of the Moon and the Sun relative to Earth? 2. How do the positions of the Moon and the Sun relative to Earth affect their gravitational pulls on Earth? What does this have to do with tides? 158

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6E3D Waves, Currents, and Tides

Reading Science Name:

Date:

Group:

Ocean Tides 1

The gritty sand oozes between your toes as you stroll along the beach. The gentle lapping of the waves lulls you into a peaceful state. The ocean water appears to stretch its cool fingers farther up onto the shore than it did earlier in the day. Is it your imagination or is the water level rising?

Well, you may feel better knowing that it is not your mind playing tricks on you. Throughout each day, the ocean water rises and falls at different times. This movement of water is known as a tide. A tide is a change in water level at the shoreline; it is being caused by the pull of gravity between Earth and the Moon and Earth and the Sun. During each 24-hour period, the beach will experience two high tides and two low tides in most places around the world. Periodically, the beach will also experience a spring tide and a neap tide.

How does the gravity between the Moon and Earth cause a tide? Each day, the beach can expect a high tide, a low tide, another high tide, and then another low tide. Between each of these tides is approximately six hours. This is important to know because each quarter turn of Earth takes six hours. Earth will make four quarter turns in a 24-hour period. With each turn, the Earth and the Moon will be in different positions. These positions determine if it is a high or low tide. These tides are a direct effect of the Moon’s gravity tugging on the water on Earth.

The Moon’s gravity has a powerful effect on Earth’s waters. In fact, it is far more powerful than the Sun’s effect. Why, you ask? It is because the Moon is closer to Earth than the Sun. The Moon pulls the water that is on the side of Earth facing the Moon toward itself in a big bulge. At the exact same time, on the side of Earth that is facing away from the Moon, another bulge is forming. These two places will experience high tides. The opposite places on Earth, which are not facing toward or away from the Moon, will experience low tides. As Earth keeps making quarter turns, the tides change from high to low and low to high.

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Reading Science Continued 5

How does the Sun affect the ocean tides? As mentioned before, the Sun has less of an effect on the tides. However, the gravitational tug of the Sun can increase a high tide by making it rise higher than normal. This is known as a spring tide. A spring tide has absolutely nothing to do with the season spring. A spring tide happens when the Moon is either in its new moon or full moon phase. The Moon, Sun, and Earth line up perfectly with one another. This allows their gravitational pull on the ocean to work together making the high tide rise higher.

A neap tide is the opposite of a spring tide. A neap tide is a lower than normal high tide. At the same time, there is also a higher than normal low tide. This happens as the Moon enters a first and last quarter moon phase. At this time, the Sun and the Moon are in positions that form a right angle to one another. The gravitational pull of the Sun pulls water away from the bulge formed by the Moon at high tide. The water moves toward the places that are having low tides. This results in a low high tide and a high low tide.

In a 24-hour period, a beach will have two high tides and two low tides. When the Moon is new or full, it will line up with the Sun and Earth causing a spring tide. When the Moon and the Sun form a right angle to one another, there will be a neap tide. The next time you visit a beach, pay attention to the water level on the shoreline. You might just experience a high or low tide yourself. As you do, remember that the gravitational pull of the Moon is what is causing the ocean tides.

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Reading Science 1.

Which statement best describes what an ocean tide is? A

A change in water level that makes a high tide higher

A change in water level at the shoreline that is being caused by the gravitational pull of the Moon

A change in water level at the shoreline that is being caused by the gravitational pull of the Sun

A change in water level that makes a low tide lower

What effect does the Sun have on the ocean tides? A

The Sun does not have an effect on the ocean tides because it is too far away.

The Sun warms the water causing it to rise.

The gravitational pull of the Sun causes spring and neap tides.

The gravitational pull of the Sun’s gravity is more powerful than the Moon’s.

During a spring tide, the Moon is either in its new moon or full moon phase. What effect does this have on an ocean tide? A

The Moon, Sun, and Earth line up perfectly with one another, allowing their gravitational pulls to work together and making the high tide rise higher.

The Moon and Sun are positioned at a right angle to one another causing a lower than normal high tide. The Sun warms the water causing it to rise.

In most places, the beach will experience two high tides and two low tides.

A spring tide only happens during the springtime.

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Reading Science 4.

How does the gravity between the Moon and Earth cause the tides to rise and fall? A

The position of the Sun interferes with the Moon’s gravity.

During each quarter turn that Earth makes, the Moon and Earth line up in different positions allowing for the high and low tides.

Earth makes four quarter turns each day causing spring and neap tides.

The gravity of the Moon is stronger at night than during the day.

What is the main point of paragraph 3? A

Solar flares affect the tides.

Tides are not affected by the Moon’s orbit.

The neap tide is the opposite of the spring tide.

Gravity between the Moon and Earth causes different tide levels.

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6E3D Waves, Currents, and Tides

Math Connections Name:

Date:

Group:

Waves are most commonly caused by wind. The greater the wind speed and duration, the larger the wave created. Wind-driven waves, or surface waves, are created by the friction between wind and surface water. As wind blows across the surface of the ocean or a lake, the continual disturbance creates a wave crest. The Beaufort Scale is used to make predictions about wave height based on the wind speeds over the water. Use the scale below to answer questions on the following page. Description

Beaufort Number

Wind

Wave

Calm

Wind Speed (m/s)

Probable Wave Height (m)

0–0.2

Light Air

Ripples

0.3–1.5

0.1

Light Breeze

Small Wavelets

1.6–3.3

0.2

Gentle Breeze

Large Wavelets

3.4–5.4

0.6

Moderate Breeze

Small Waves

5.5–7.9

1.0

Fresh Breeze

Moderate Waves

8.0–10.7

2.0

Strong Breeze

Large Waves

10.8–13.8

3.0

Near Gale

Large Waves

13.9–17.1

4.0

Gale

Moderately High Waves

17.2–20.7

6.0

Strong Gale

High Waves

20.8–24.4

7.0

Storm

Very High Waves

24.5–28.4

9.0

Violent Storm

28.5–32.6

11.5

12-17

Hurricate

32.7–61.2

> 14.0

Exceptionally High Waves Exceptionally High Waves

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Math Connections The graph below shows the wind speed over St. Andrew Sound, Georgia from March 17–20, 2016. Use the graph below and the Beaufort Scale on page 1 to answer the questions below.

Use the Beaufort scale to predict the swell height for the wind speeds shown on the graph. Plot the corresponding swell heights on the graph above and connect the points with a blue pencil. 1.

According to the Beaufort Scale, how would you describe the wind on March 18 at 8 a.m.? ___________________

According to the Beaufort Scale, what type of waves would you expect to see on March 18 at 8 p.m.? _______________________

Use the Beaufort Scale to predict the swell height on March 20 at 2 p.m. _______________m

How much greater will the predicted swell height be on March 20 at 2 p.m. than 2 a.m.? _____________ m

Based on the data in the graph, what day is the wind transferring the most energy to the surface water? How do you know? _______________________________________________ ___________________________________________________________________________ ___________________________________________________________________________

Write a short four-day forecast for fishermen on the water. What can they expect the winds and waves to be like? What would be the optimal time to fish in calm water? __________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________

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6E3D Waves, Currents, and Tides

Writing Science Name:

Date:

Group:

LOOK

THINK Think about how the sun’s energy powers the water cycle. WRITE Explain how the convection currents in fluids (air and water) influence our weather as well as ocean currents. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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Writing Science

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6th Grade Earth and Space Science

6E4A

Composition of Earth’s Atmosphere

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6E4A Composition of Earth’s Atmosphere

Student Journal Name:

Date:

Group:

Atmospheric Layer Puzzles Use the information from the atmosphere layer puzzles to complete the chart below.

Atmospheric Layers (in order)

Distance Above Earth

Temperature Range

Air Pressure

Does weather occur here?

Exosphere (closest to space)

Thermosphere

Mesosphere

Stratosphere

Troposphere (closest to Earth)

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Student Journal Use the information from the atmosphere layer puzzles to complete the chart below.

Atmospheric Layers (in order)

Other Interesting Facts

Exosphere (closest to space)

Thermosphere

Mesosphere

Stratosphere

Troposphere (closest to Earth)

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Student Journal Reflections and Conclusions 1.

Which layer of the atmosphere is the thickest? Explain your answer.

How does air pressure change as you travel higher above Earth’s surface?

Which layer of the atmosphere contains ozone?

How does ozone protect us?

Does the temperature consistently increase or decrease as you move through the layers of the atmosphere? Why do you think that is?

The gases thin out as you travel up from Earth toward space. Because of this, where are most of the greenhouse gases found?

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Student Journal 7.

Using your data table, complete the following Venn diagram to compare and contrast the listed atmospheric layers.

Stratosphere

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Mesosphere

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STEMscopedia: COMPOSITION OF EARTH’S ATMOSPHERE

6E4A

Reflect What do you know about Earth’s atmosphere? Let’s begin by first defining atmosphere. Earth’s atmosphere is the combination of gases that surround our planet. Our atmosphere is a mixture of approximately 78% nitrogen, 21% oxygen, and 1% other various gases. Without our atmosphere, life would not be supported here on Earth. Earth’s atmosphere has five layers. The higher you go above our planet, the thinner our air becomes. Eventually, you will leave our atmosphere and enter space. Each atmospheric layer has unique characteristics to make it different from the rest of the layers. Look at the image to see where each layer is located. troposphere: The troposphere is the closest layer to Earth, and it is about 4 to 12 miles thick. This is where most weather and clouds occur. It is the most dense layer and makes up almost four-fifths of Earth’s air. The air in this layer gets colder the higher you go. stratosphere: The stratosphere is the layer directly above the troposphere. It ends about 31 miles above our ground. This is where Earth’s atmospheric layers the ozone layer is found. The ozone layer is important because it helps create a blanket of air block some of the most harmful radiation from the Sun. Because of this, surrounding our planet. The the stratosphere is warmer than the troposphere. Aircrafts usually fly in atmosphere is held in place this layer. by Earth’s gravity. mesosphere: The mesosphere sits on top of the stratosphere. It is about 23 miles thick. The temperature in this layer drops significantly to almost -180 degrees Fahrenheit. This is where meteors typically burn up as soon as they enter our atmosphere. thermosphere: This is the second highest layer in our atmosphere. The temperature in this layer slowly increases with height. The density of this layer remains low due to the low density of its air molecules. There are no clouds or water vapor in this layer. The International Space Station orbits within the thermosphere. exosphere: This is the uppermost layer of Earth’s atmosphere. This layer merges with outer space. It is made up of hydrogen and helium, which are gases with extremely low densities, and some heavier molecules, such as nitrogen, oxygen, and carbon dioxide. This is where most satellites orbit Earth.

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What Do You Think? A factor that allows Earth to support life is the planet’s ozone layer. Although heat and light from the Sun make life possible on Earth, other forms of energy from the Sun threaten life on Earth. These include charged particles, positively charged protons and negatively charged electrons. They also include ultraviolet (UV) radiation. Two characteristics of Earth help protect its living things from the Sun’s harmful radiation. These characteristics are Earth’s magnetic field and its ozone layer. Ozone is a molecule of oxygen made up of three atoms of the gas (O3). Most molecules of oxygen found in Earth’s atmosphere consist of two atoms of oxygen (O2). The ozone layer is a thin concentration of ozone high in Earth’s atmosphere. The ozone layer is most concentrated about 23 kilometers above Earth’s surface. Ozone protects life on Earth by absorbing ultraviolet radiation, especially a form called UVB. UVB causes sunburn, skin cancer, and cataracts in humans. UVB can also harm some crops and forms of ocean life. As anyone who has suffered from sunburn knows, a lot of UVB radiation does get through the ozone layer. Without the ozone layer, however, even more harmful radiation would reach Earth’s surface. Has our ozone changed over the years? The ozone layer is definitely changing on a daily basis. The release of harmful chemicals into the air causes a breakdown of molecules in the ozone layer, which results in the ozone layer being less capable of protecting us from harmful ultraviolet rays from the Sun. Look at this image of the Arctic ozone layer in 2010 compared to 2011. Look at the scale at the bottom of the image. The ozone layer’s thickness is measured in Dobson units. A normal range is anywhere between 300 and 500 Dobson units. As you can see from this image, the ozone layer in 2011 is much thinner than in 2010. What do you think will happen to the ozone layer in 50 years if we continue to pollute our air?

Look Out Earth’s atmosphere serves many purposes besides helping support life on our planet. The atmosphere protects us from celestial objects, such as meteorites, crashing into our planet. In addition, if there was no atmosphere, we would face deadly radiation from the Sun. Our atmosphere acts as a barrier to prevent these harmful things from affecting our planet and causing danger to people, animals, and all other living organisms. It is our job to protect our atmosphere the best way we can, so that it, in turn, can continue to protect us. Humans have created dangerous air pollution with harmful gases from factories and vehicles. It is important that we stay mindful of what we are releasing into our air. Once it is released, we cannot undo the damage that has been done.

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Using cleaner fuels, driving our cars less, and making sure our factories have devices to control what enters the air are all ways we can help protect our atmosphere. What are some other ways we can protect the blanket of air surrounding our planet? Factories can reduce pollution by “pollution control” and switching from coal to natural gas. Pollution control involves putting a cap on the end of a pipe to help trap harmful gases from escaping into the air.

What Do You Know? How does our planet stay at the “perfect” temperature to support life? The answer comes from the greenhouse effect. This process uses radiation from our atmosphere to warm Earth’s surface. Without an atmosphere, our planet would be too cold to support life. The process begins with solar radiation entering Earth’s atmosphere. From there, some radiation is reflected back into space, while the rest is absorbed by Earth’s surface. Infrared radiation (heat) is then emitted from Earth’s surface back into the atmosphere where it is then trapped by greenhouse gases.

Earth’s atmosphere traps some of the Sun’s energy at the planet’s surface.

Try Now Read the following statements and label them with the correct atmospheric layer. The layer where most weather occurs. ____________________________ The layer that contains ozone. ____________________________ The layer where most satellites orbit Earth. __________________________________ The layer with the highest temperatures. _______________________________ They layer where aircrafts can fly. ________________________________ The layer that touches Earth’s surface. ______________________________ The layer that protects Earth from meteorites. ________________________________ The layer where temperatures drop as low as -180 degrees Fahrenheit. _______________________ The layer where the International Space Station orbits. _________________________________

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Connecting With Your Child To create a deeper understanding of the relative size of the atmospheric layers, you and your child will create a visual representation of the first four layers (troposphere, stratosphere, mesosphere, and thermosphere). You will need the following materials: • • •

2 1,000-mL graduated cylinders (You might be able to borrow this from your child’s classroom teacher.) 1 100-mL graduated cylinder (You might be able to borrow this from your child’s classroom teacher.) 4 different colors of sand

Set the 1,000-mL graduated cylinder on a table. Explain that the table represents Earth and the air above the table represents the atmosphere. Use the 100-mL graduated cylinder to measure out the first three sand amounts. Pour 15 milliliters of one color of sand into the large graduated cylinder. Pour 45 milliliters of a different color of sand on top of the first color. Pour 45 milliliters of a third color of sand on top of the second color of sand. Use the other 1,000-mL graduated cylinder to pour the last sand amount. Pour 895 milliliters of the last color of sand on top of the third color. Discuss what each of the sand colors represents in terms of Earth’s atmospheric layers. Use the following questions to guide your discussion: 1. Which atmospheric layer is represented by each color? 2. How much thicker is the second layer compared to the first layer? 3. How much thicker is the fourth layer compared to all the other layers combined? 4. Where in this model would you find weather occurring? 5. Where in this model do satellites orbit Earth?

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6E4A Composition of Earth’s Atmosphere

Reading Science Name:

Date:

Group:

Few Elements, Many Compounds 1

Think of the English alphabet. Millions of words can be made from only 26 letters! The same thing is true of elements and compounds. It takes a few common elements (the basic form of matter that cannot be broken down any further) to make most of the planet’s many compounds, including rocks (solid earth), air, water, and even people.

Let’s take a trip to Maui in the Hawaiian Islands. When you cross the Pacific Ocean, you are traveling across seawater that is made of hydrogen, oxygen, sodium, chlorine, and traces of other elements. Pure water has only hydrogen and oxygen. When you first get to the island, you will probably walk on sand, which is actually tiny bits of worn-out rock composed largely of oxygen and silicon. A nice tropical breeze hits your face; it consists of nitrogen, oxygen, a little argon and carbon dioxide, and small amounts of other gases.

As you walk around, you will notice volcanic rocks and mountains on the island that are made up of mixtures of oxygen and silicon with magnesium, aluminum, potassium, iron, and small amounts of other elements. Green volcanic rock, which is also in abundance on the island, has a heavy concentration of iron and magnesium.

You are sure to notice all the plants and animals. The Hawaiian Islands contain much diversity, and your focus rests on the beautiful trees, bushes, and flowers. A Hawaiian tree, a beautiful purple orchid on that tree, and a beetle crawling on the ground—these are all examples of living matter composed of the elements hydrogen, oxygen, carbon, and nitrogen, with hydrogen being the most abundant.

As you leave Hawaii, you marvel at what you’ve seen and how so many compounds can be made from so few elements. Through chemical changes, a few simple elements can be turned into many different things.

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Reading Science 1.

What is the basic form of matter that cannot be broken down any further? A

A compound

An element

A chemical reaction

An organism

Which of the following elements do living things have that volcanic rocks do not have? A

Oxygen

Silicon

Magnesium

Carbon

Which of the following best summarizes the passage? A

Volcanic rocks and mountains are on Hawaiian islands.

Green volcanic rock has a heavy concentration of iron and magnesium.

Sand is tiny bits of worn-out rock made mostly of oxygen and silicon.

A few common elements make most of the planet’s many compounds.

What is the main point of the reading? A

A few elements combine to make many compounds.

Many elements combine to make a few compounds.

Elements cannot be combined except by artificial means.

Hawaii is made up of only a few types of compounds.

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Reading Science

This chart shows the compounds that make up the air. The rectangle on the right is an expanded view of the smallest wedge of the pie chart. What percentage of air is oxygen? A

0.07%

0.93%

21%

78%

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6E4A Composition of Earth's Atmosphere

Math Connections Name:

Date:

Group:

Earth’s atmosphere is made up of many elements. The table below includes a few of those elements and the portion of Earth’s atmosphere they represent. Complete the data table below for 1–5. Element Name 1. Nitrogen 2. Oxygen 3. Argon 4. Carbon Dioxide 5. Trace gases and water vapor

Percent

Fraction 39/50

Decimal 0.21

0.93% 1/2500 0.0003

The atmosphere includes the air that surrounds Earth. It is comprised of five layers: troposphere, stratosphere, mesosphere, thermosphere, and exosphere. Use the measurements of the radius of each layer from the center of Earth to calculate the surface area and volume for each layer. Use scientific notation to help record and compare the sizes of the layers. π = 3.14 Radius from Thickness of Center of Layer Earth

Surface Area 4πr2

Earth

6,378 km

5.11 x 108 km2 1.08 x 1012 km3

6. Troposphere

6,392 km

14 km

7. Tropopause

6,396 km

4 km

8. Stratosphere

6,428 km

32 km

9. Mesosphere

6,468 km

40 km

10. Thermosphere

6,778 km

310 km

11. Exosphere

16,378 km

10,000 km

Atmospheric Layer

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Volume 4πr3/3

Volume Previous Layer --

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6E4A Composition of Earth’s Atmosphere

Writing Science Name:

Date:

Group:

Look

Think Think about the different layers that compose the atmosphere. Think of the temperature, pressure, and mixture of gases that make up each layer.

Write Compare the composition and properties of each layer of Earth’s atmosphere.

Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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Writing Science

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6th Grade Earth and Space Science

6E4B

Sun’s Energy on Earth

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6E4B Sun’s Energy on Earth

Student Journal Name:

Date:

Group:

Thermal Energy Part I: Temperature and Thermal Energy Transfer 1.

What is temperature?

What is thermal energy?

How does the temperature of the ice chip compare to the temperature of your hand?

In the example of holding ice, what evidence indicates that thermal energy transfers?

In the example of holding ice, where does the thermal energy come from?

In the example of holding ice, where does the thermal energy go?

Using the example of holding ice, explain when the thermal energy transfer stops.

Can you summarize how thermal energy moves from one object to another?

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6E4B Sun’s Energy on Earth

Student Journal Part II: Conduction 1.

Data Table: Melting Wax Chips by Conduction

Chip

Time 2.

Use the drawing below to illustrate what you observed. Use labels and arrows to identify the transfer of energy.

What type of heat transfer occurs along the aluminum foil?

What pattern was evident in the movement of thermal energy?

What evidence did you observe that showed heat transfer?

In your own words, define conduction.

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6E4B Sun’s Energy on Earth

Student Journal Part III: Convection 1.

Draw a lava lamp and show what happens to the blob you observe. Use arrows and labels to identify the parts of the lamp and the heat transfer.

Draw the can of cooking fuel and what you observed on the wall or board. Use arrows and labels to identity the set up and the heat transfer. Be sure to show where the heat near the ceiling went.

In which state of matter did the transfer of thermal energy occur in the lava lamp?

In which state of matter did the transfer of thermal energy occur when you observed the cooking fuel?

When observing the cooking fuel demonstration, the shadow eventually disappeared. What happened to the heat in this system?

In your own words, define convection.

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6E4B Sun’s Energy on Earth

Student Journal Part IV: Radiation 1.

Record your data in the boxes below Radiometer at 20 cm

Radiometer at 15 cm

Radiometer at 10 cm

Did the vane move?

Beginning temperature

Temperature after 3 min

Graph the ending temperatures for each location of the radiometer.

Fill in the blanks using the data you recorded: a. As the distance increased, the temperature__________________________. b. As the distance decreased, the temperature __________________________.

In your own words, define radiation.

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6E4B Sun’s Energy on Earth

Student Journal Reflections and Conclusions 1.

Identify the type of energy transfer (conduction, convection, or radiation) for each description below. Example of Heat Transfer

Conduction, Convection, or Radiation

Hot chocolate is stirred with a spoon, and the spoon gets hot. The Sun warms your skin on a cold day. Macaroni rises and falls in a pot of heated water. You burn your hand by touching a hot stove. You warm your feet in front of a fire. Hot air balloon rises. The air near the ceiling in a room is warmer than the air near the floor. The material in a lava lamp rises and falls. The sidewalk increases in temperature on a sunny day. The sidewalk burns your bare feet in the summer time.

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6E4B Sun’s Energy on Earth

Student Journal Reflections and Conclusions, continued 2.

When particles of matter are in direct contact, conduction of thermal energy occurs in which states of matter?

When particles of matter are in direct contact and movement occurs in the substance due to convection, thermal energy transfers in which states of matter?

Which states of matter are required for energy transfer to occur when radiant energy is the source?

Use your data from Part II to draw a conclusion. In thermal energy transfer by conduction, how does heat move between objects that are touching?

Use your data from Part III to draw a conclusion. In thermal energy transfer by convection, what is the pattern of heat transfer through fluids?

Use your data from Part IV to draw a conclusion. In thermal energy transfer by radiation, how does distance from the thermal energy source affect the amount of thermal energy transfer occurring in a substance?

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Student Journal Name:

Date:

Group:

Explore 2: Heat Transfer in Earth’s Systems Thermal Energy Transfer Problem: Design an investigation that will model how Earth’s air, water, and soil heat at different rates. Question: Write a question that you are trying to answer in this investigation. ______________________________________________________________________________ Hypothesis: Write a sentence that describes what you think will happen in this investigation. ______________________________________________________________________________ Materials: In the space below, list the materials you plan to use in your investigation.

Independent variable: ____________________________________________________________ Dependent variable: _____________________________________________________________ Controlled variables (list at least three): _____________________________________________ _______________________________________________________________________________

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Student Journal Procedures: 1.

In the space below, draw a picture of how you plan to set up this experiment. Label your drawing.

Steps I will complete in this investigation:

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6E4B Sun’s Energy on Earth

Student Journal Data Table: Trial 1

Trial 2

Trial 3

Average Temperature

Soil Air Water

Graph:

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Student Journal Reflections and Conclusions 1.

What are three ways that heat is transferred on Earth?

In which direction does heat travel?

The Sun’s energy heating Earth is an example of what type of heat transfer?

In your investigation, were other types of heat transfer possible? If so, what and where?

Did you get the results you expected? Explain your answer.

In this investigation, you created a model of the Sun’s energy heating systems on Earth. How could you make your model better?

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STEMscopedia: SUN’S ENERGY ON EARTH 6E4B

Reflect Have you ever been to the beach on a hot summer day and tried to walk across the sand on your bare feet? It can be so hot that you run to the water and step in the ocean to cool off your burning feet. If the sand and water are exposed to the same heat source, why is there a difference in the way they feel? Have you ever taken a walk on that same beach later that night? The sand feels chilly and refreshing on your feet, while the water feels warm in comparison. How can this be explained?

Heat vs. Temperature Before investigating heat transfer from the Sun to Earth, you must understand what is meant by heat. Heat and temperature are often used interchangeably, but the two terms have different meanings. Heat is a form of energy caused by the motion of atoms. The faster atoms move, the more heat energy they contain. Heat is a measure of all the kinetic energy of all atoms in a sample of matter.

Temperature is a measure of the average speed of atoms, and it is measured in units called degrees. The faster the atoms are moving, the higher the temperature is.

What Do You Think? Which contains more heat: a large pot full of boiling water or a small mug full of boiling water? Which contains more heat: a 25-yard swimming pool heated to 75°F or a large pot of boiling water heated to 212°F? Which has a higher temperature: a large pot of boiling water or a small mug of boiling water? Which has a higher temperature: a 25-yard swimming pool heated to 75°F or a large pot of boiling water (212°F)?

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STEMscopedia: SUN’S ENERGY ON EARTH Look Out Many people do not understand how heat energy is transferred. Have you ever heard someone say, “Quick, shut the door. Don’t let the cold air in.”? In reality, they should say, “Quick, shut the door. Don’t let the heat out.” Heat energy is transferred between objects with differences in temperature. Heat energy moves from objects with higher temperatures to objects with lower temperatures in an effort to reach equilibrium. Think back to the scenario from the Reflect section. Since the Sun is the main source of energy for Earth, how does the Sun transfer its heat energy to Earth? And why does it appear to transfer heat unevenly or at different rates? Heat is transferred between bodies in three different manners: radiation, conduction, and convection. Radiation Radiation refers to heat energy transfer that occurs through electromagnetic radiation. Radiation travels in waves. An example of heat transfer from radiation is the heat you feel from a fire. If you stand near a campfire, you feel the heat radiating from it, even though you are not actually touching it. How does radiation affect how the Sun warms Earth? Radiation is the method by which the Sun’s heat reaches Earth. It travels through outer space in waves. Radiant heat from the Sun is the source of most of Earth’s heat energy. Conduction Conduction refers to the transfer of heat energy from one object to another through physical contact. Heat is passed from one object to another when objects are touching and there is a temperature difference between objects. Heat energy passes from an object with a higher temperature to an object with a lower temperature until the objects are the same temperature. Conduction is an especially effective method for heating solids because atoms in solids are packed close together and solids have a fixed structure that keeps atoms contained. An example of conduction is a metal frying pan placed on an electric burner. The atoms of the pan are heated by conduction. First, the atoms touching the burner heat up and begin to vibrate faster. Then the heated atoms touch atoms next to them, which heats those atoms and cause them to vibrate faster. This action is repeated over and over until all of the atoms in the metal are the same hot temperature—like a crowd at a football game doing the wave. The Sun heats Earth by conduction in this same manner. Although sunlight travels through space as radiant energy, once sunlight falls on the surface of Earth and heats it, heating by conduction begins. Once an atom has been heated, it speeds up and heats the atoms that touch it, and they heat the atoms they touch.

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STEMscopedia: SUN’S ENERGY ON EARTH How could the method of conduction result in uneven heating for solids versus liquids or gases? The answer lies in the density and the structure of the atoms in each substance. Because atoms of solids are packed so closely together and are fixed in place, it is easier for atoms to become heated, vibrate more rapidly, touch the atoms next to them, transfer heat energy, and repeat this process quickly, furthering the heating process. Properties of liquids mean the atoms in liquids are not confined to a certain shape or structure and are not packed as closely together as solids. As liquids flow, it takes longer for them to “bump into” an atom that is a heat source and gain heat through direct contact. This is even more apparent with gases, in which the atoms are spread even farther apart since gases have no fixed shape or volume. Therefore, the heat transfer of conduction works fastest to heat solids; liquids are heated more slowly; and gases are heated the most slowly by conduction. The same is true in reverse as well. Solids lose heat rapidly when a heat source is removed. When we apply what we know about conduction to the Sun’s heating of Earth, the same principles about the rates of heating solids, liquids, and gases apply. For instance, sand (a solid) is heated more rapidly than water (a liquid), and water is heated more rapidly than air (a gas) when exposed to direct sunlight. The heating of Earth’s environment is not that simple, however, because conduction typically does not happen in isolation. It is usually one aspect of heat transfer that occurs in tandem with convection and radiation. Convection Convection refers to the transfer of heat energy through the motion of fluids, such as air and water. For example, to boil a pot of water, conduction is used to heat the pot, but the water in the pot is heated by convection. The water molecules at the bottom of the pot receive heat energy, move faster, and expand. When the heated water expands, it becomes less dense because it has the same number of molecules (or mass) but takes up a larger space (or volume). Since density is mass per volume, the density of heated water is less than the density of cooler water. Because the heated water becomes less dense than the cooler water at the top of the pan, the heated water rises, causing the cooler water at the surface to sink because it is denser. The cooler water that sinks to the bottom then becomes heated and rises, resulting in convection currents that circle in the pot and heat the water. How does convection relate to the Sun’s heating of Earth? Even though the Sun’s energy travels to Earth as radiant energy, convection plays a major role in the heating and cooling of Earth, due to Earth’s atmosphere being composed of gases and Earth’s surface being largely covered with water. Both air and water are good candidates for heat transfer through convection since they both flow.

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STEMscopedia: SUN’S ENERGY ON EARTH The Sun heats the surface of Earth, and the air near the surface of Earth is heated by conduction. This air warms, expands, and rises, taking the place of cooler air. Where warm air is rising, air pressure is lessened, allowing for cooler air from an area of higher pressure to rush into the vacated spot. Eventually, the warm air that rose cools (because it is away from the heated surface of Earth), and the cool air that sank is heated (because it is close to Earth’s heated surface). The newly heated air rises, while the risen air that has cooled sinks, repeating the convection process and causing convection currents. The surface of the ocean is warmed by radiant heat from the Sun, causing water molecules to heat and evaporate into the air as water vapor, joining in the process of convection with the air. This also activates the water cycle. In addition, the heating of the oceans causes convection to occur, which is one of the causes of ocean currents that help regulate Earth’s climate. Heat transfer through convection is not successful with solids because molecules in solids are fixed in place and cannot rise and fall when heated and cooled. Because solids do not flow, they cannot experience heating through the convection process. Methods of heat transfer work together. Radiation, conduction, and convection often work together to efficiently heat matter. Think of how sap is boiled to make maple syrup. A fire is built, and the pot is hung over the fire. Radiation from the fire heats the pot. The liquid at the bottom of the pot is heated by conduction. The rest of the liquid is then heated by convection until it is boiling and uniformly heated. The same “cooperation” happens with heat transfer from the Sun to Earth, involving radiation, conduction, and convection. Radiation transports the Sun’s heat energy to Earth and heats the surface of Earth. Conduction then transfers heat energy through atoms that make physical contact. Conduction is most effective with solids, such as sand at the beach or sidewalks or streets, because atoms are close together. Once the surface of a solid or liquid is heated, other matter (solid, liquid, or gas) that comes into contact with it is also heated. Convection then occurs with liquids and gases as changes in density happen due to uneven heating. This, in turn, results in such phenomena as the water cycle, winds, ocean currents, and other processes here on Earth.

What Do You Know? Look at the images below. Convection near coastlines causes “sea breezes” to occur during the day and “land breezes” to occur at night. Write a paragraph to explain your reasoning behind this phenomenon. Hint: Think of unequal heating of liquids and solids caused by conduction.

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STEMscopedia: SUN’S ENERGY ON EARTH Connecting With Your Child Also, remember that when air rises, air pressure in that area drops, allowing for air from an area of higher pressure to rush in. Heat Transfer by Conduction in Action To help your child comprehend the process of conduction, try doing a simple experiment together to witness conduction in action. You will need the following materials: a candle, a metal ruler (or flat metal object of a similar shape), a small birthday cake candle divided into four pieces, and an oven mitt. Procedure: On top of the ruler, place a small piece of a candle at the following locations: 4 inches away of one end of the ruler, another 4 inches farther, and at the other end of the ruler. Light the candle. Wearing the oven mitt, carefully hold one end of the ruler over the candle flame, keeping the ruler level so the bits of candle do not fall off. Observe what happens to the bits of birthday candle. After each bit of birthday candle has experienced a change, carefully set the ruler down and blow out the candle. Be careful not to touch the ruler for a few minutes, as it will still be hot. Here are a few questions to discuss with your child: 1. What happened to the bits of birthday candle? 2. What did you notice about the order in which the candle bits melted? Why do you think they melted in that particular order? 3. What do you think would have happened to the small areas of liquid wax if you had put the end of the metal ruler into a cup of ice water right after the last bit of birthday candle melted? Why? 4. How does this experiment demonstrate what you have learned about conduction from the Sun’s energy on Earth?

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6E4B Sun’s Energy on Earth

Reading Science Name:

Date:

Group:

What Does Calorimetry Tell Us? 1.

There is nothing like living in hot, windy West Texas. A warm, spring day can bring gusts of 20 miles per hour or more. Hold on to your hat, because it may blow away! The constant wind is just a way of life. The wind does not blow just in Texas. It blows all around the world. As the wind grabs your hat, have you ever wondered what makes it blow? Where does the wind come from? Wind is air in motion. Energy from the Sun heats up the surface of Earth. Heat energy then transfers to the air.

Think about what the surface of Earth is like. With mountains, hills, rivers, and oceans, the surface is uneven. Every landform or body of water absorbs heat from the Sun at different rates. As a result, the air above these locations warms at different rates, too. This causes movement in the air. As warm air rises and expands, cool air rushes in to take its place. The Sun is not only the source of energy for all living things. It is also the driving factor in creating the wind.

Wind can be a powerful form of solar energy—energy that comes from the Sun. Wind is known as a renewable energy source. There is an endless supply. Therefore, wind may be a good alternative to use instead of fossil fuels. Businessmen have been taking advantage of this. Maybe you have noticed giant windmills starting to pop up on the landscape. Harvesting wind energy is a rapidly growing industry.

Wind farms are groups of windmills that are used to harness the wind. There are many wind farms all over the world. The largest one is in Texas. The Horse Hollow Wind Energy Center is located in Taylor and Nolan Counties. It has 421 windmills. It can produce enough electricity to power 220,000 homes per year.

Windmills work when the wind blows around the blades. This makes them turn. The windmill captures kinetic energy, the energy of motion, from the wind. The windmill converts the kinetic energy into mechanical power. A generator converts the mechanical power into electricity for homes and businesses. Windmills come in different sizes. The largest windmill’s blades are longer than the length of a football field. They can stretch 20 stories high. This size can generate electricity to power 1,400 homes. The smallest windmill’s blades are between 8 and 25 feet and only reach 30 feet high. This size can easily power a single home or business.

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Reading Science 6.

Wind farms affect the environment in both positive and negative ways. Windmills cause little to no pollution. All anyone needs to harness the wind’s power is a windmill and the wind. Windmills can be set up in remote locations, as long as the area has a consistent wind. We want to use more energy that comes from renewable sources like wind. That way we will need less energy from fossil fuel resources. This is good because burning of fossil fuels is bad for the environment. It causes pollution and produces greenhouse gases.

For the most part, windmills have a positive impact on Earth. There are still a few negative ones, however. One problem of wind energy is that the wind doesn’t always blow when electricity is needed. Wind cannot be stored. Therefore, alternative power plants must sometimes be used for electricity. Another negative is that sometimes birds and bats fly into the blades of windmills. They can be injured or killed. Large fields of windmills also change the habitat of all the animals in the area. Most of the large wind farms are built in remote locations. Some of these regions are known for their natural beauty. Some people have objected because they don’t like the way the windmills look. They complain that windmills are big and ugly. They feel these wind farms ruin the beauty of the landscape.

All in all, it is worth considering turning wind energy into electricity. It could be a good option to power homes and businesses. Scientists are looking for ways to reduce the negative impacts of windmills on the environment. The positive impacts of wind energy make it an attractive energy source for the future. After all, the Sun provides energy for all living things in many ways. The Sun helps plants grow, warms Earth’s surface, provides light, and makes the wind blow. The next time you feel a breeze, think about how that gust could power your house.

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Reading Science 1.

What causes the wind to blow? A

The solar energy from the Sun pushes the air into the atmosphere.

As warm air rises, it rushes sideways past you, making the air move.

Warmer temperatures in the spring cause the wind to blow.

The uneven heating of Earth’s surface causes warm air in some locations to rise and expand. Cool air rushes in to take its place.

Why is wind known as a renewable energy source? A

Wind energy comes from the Sun.

Wind is not recyclable. There is a limited supply of it on Earth.

There is an endless supply of wind.

Windmills can be placed anywhere that the wind blows.

Which statement best describes one positive impact that wind energy has on Earth? A

Windmills provide a constant source of inexpensive energy.

Some people do not like the appearance of the windmills.

By using wind energy in place of fossil fuels, the amount of pollution is reduced.

Windmills can alter an animal’s natural habitat.

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Reading Science 4.

How does a day that is not windy affect the production of electricity? A

It doesn’t have an effect. The wind is endless.

Houses or businesses would not be able to use as much electricity on that day.

The windmill would produce electricity anyway because it doesn’t need the wind to make it turn.

Wind cannot be stored. Alternative power sources would have to be used.

Which statement most likely matches the author’s opinion of the future of wind power? A

Wind energy is an alternative energy source which should be used more in the future.

The negative and positive aspects of wind energy are closely matched. It is debatable whether it can ever be a useful energy source.

Wind energy is the only workable solution to an energy crisis.

Wind is not a good energy alternative.

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6E4B Sun's Energy On Earth

Math Connections Name:

Date:

Group:

Heating Earth’s Surface Radiant (solar) energy from the Sun heats Earth’s surface. However, Earth does not absorb all of that energy. The chart below represents the outcome of radiant energy as it travels through the atmosphere. Outcome of Radiant (Solar) Energy Reflected back to space by clouds, atmospheric particles, or ice and snow Absorbed in the atmosphere by water vapor, dust, and ozone Passed through the atmosphere and absorbed by Earth’s surface

Percentage of Solar Radiation 29 23 48

Solar energy falls to Earth at approximately 340 watts per square meter. Based on the percentages above, how much of that energy is absorbed into Earth’s surface?

How much of that energy is absorbed into the atmosphere?

For Earth’s temperature to remain stable, its atmosphere and surface must radiate an equivalent amount of thermal energy back into space. What percentage of the Sun’s energy does Earth’s surface and atmosphere absorb?

Based on your calculations and the data in the table, where does most of the solar heating happen? Where does most of the radiative cooling happen?

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6E4B Sun's Energy On Earth

Math Connections 5.

If Earth’s surface were to absorb only heat, Earth’s temperature would infinitely rise. Fortunately, Earth’s surface radiates back a large amount of heat. The amount of heat it radiates is represented by the equation y = t4, where t = Earth’s temperature.

If Earth’s temperature doubles, by how much does the thermal energy radiated by the Earth’s surface increase?

•

Consider Earth’s temperature at 10 degrees and at 20 degrees.

•

Write and simplify the ratio of the amount of energy Earth’s surface radiates at 10 degrees to the amount of energy it radiates at 20 degrees.

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6E4B Sun’s Energy on Earth

Writing Science Name:

Date:

Group:

LOOK

THINK Think about how the Sun transfers heat energy over Earth. This heat transfers through air, land, and water at different rates and uses the processes of conduction, convection, and radiation. Now think about the heat transfer occurring in the campfire pictured above. WRITE Explain how the processes used to heat hot dogs over a campfire are similar to those seen in the heat transfer from the Sun to Earth. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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Writing Science

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6th Grade Earth and Space Science

6E4C

Heat’s Effect on Wind Systems

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6E4C Heat’s Effects on Wind Systems

Student Journal Name:

Date:

Group:

Activity 1: Earth’s Uneven Heating Answer the following questions. 1.

What was the surface area in cm2 that the main beam covered when the flashlight was held at a 90-degree angle?

What was the surface area in cm2 that the main beam covered when the flashlight was held at a 70-degree angle?

What happened to the surface area covered by the main beam of the flashlight when the angle changed from 90 to 70 degrees?

Did the total amount of energy produced by the flashlight change when it was held at different angles?

Explain how the intensity of light received by each individual cm2 changed when the flashlight was held at different angles by filling in the blanks of the following sentence. If the same amount of energy spreads out over a ____________________ surface area, then the intensity of the light energy ____________________.

If you placed a thermometer flat on the graph paper and held the flashlight in position for five minutes at a 90-degree angle and then again for 5 min at a 70-degree angle, which flashlight position would most likely result in a higher temperature reading on the thermometer? Explain your prediction.

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Student Journal Activity I: Earth’s Uneven Heating, continued 7.

Which flashlight position is the best model for the light energy received at Earth’s equator, the 90 degree position or the 70-degree position? Which flashlight position is the best model for the light energy received closer to Earth’s poles, the 90-degree position or the 70-degree position?

Use what you learned in this activity to explain why the temperatures of equatorial regions are higher than those of polar regions.

Activity II: Earth’s Rotation and Wind Patterns Draw a diagram of your model below

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6E4C Heat’s Effects on Wind Systems

Student Journal Activity II: Earth’s Rotation and Wind Patterns, continued Answer the following questions. 1.

How is wind formed?

Explain what the activity is modeling.

What were some limitations of your models?

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Student Journal Reflections and Conclusions Answer the following questions. 1.

What system does this model represent? _________________________________

Now we know air rises and falls along certain latitudes of Earth due to a combination of convection currents and the uneven heating of Earth. Does the air fall straight down on our heads? _______________________________________

How would you describe the movement of wind?

What makes wind blow across the surface and not straight down?

What happened to your straight lines?

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6E4C Heat’s Effects on Wind Systems

Student Journal Reflections and Conclusions, continued 6.

What natural movement of Earth was modeled in the second activity?

This phenomenon is called the Coriolis effect. It deflects winds to the right in the northern hemisphere and to the left in the southern hemisphere. How do you think the Coriolis effect changes the direction of the wind on Earth?

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STEMscopedia: HEAT’S EFFECT ON WIND SYSTEMS

Reflect

6E4C

What do you know about wind? What causes it? Is it the same all around the world? Let’s find out! What causes wind? Wind is caused by differences in air pressure. Air moves from areas of ligher pressure to areas of lower pressure. Differences in air pressure are caused by the uneven heating of Earth’s surface. The Sun is the major cause of wind because it is the only heat source. As the warm, moist air rises, it creates a low-pressure zone, clouds, and precipitation along the equator. That warm air will eventually reach a point where it cannot rise any higher, and it spreads back out and cools off as it sinks back down. This sinking air produces areas of higher pressure with drier conditions. convection: transfer of thermal energy in a fluid such as air or water; warm How does unequal heating affect wind patterns? air and water rise, while The Sun is the driving force behind our You can see convection cold air and water sink weather, but our oceans play a major role in happening in a lava lamp. Earth’s weather patterns. Earth absorbs energy called solar radiation from Material at the bottom of the the Sun. Some of the energy is transferred from Earth’s surface to the lamp rises as it heats up, gases in Earth’s atmosphere through convection. As the gas molecules and then sinks back down warm up, they become less dense and rise farther into the atmosphere, as it cools. helping to distribute heat. The gas molecules higher in the atmosphere cool, becoming denser. These molecules sink toward Earth’s surface. This rising and sinking of warm and cool air create convection currents in the atmosphere. These convection currents cause air to rise and sink and move across Earth’s surface as winds. For example, during the day, land heats up faster than water. So above land, warm air is less dense and rises while the cooler air over oceans sinks, creating convection currents in the air. The wind blows toward the coast, forming a sea breeze. In contrast, during the night, land cools faster than water. Therefore, the warmer air above oceans rises, while cooler air over land sinks. This sets up a convection current that is opposite to the one during the day. Winds blow away from land, forming a land breeze.

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STEMscopedia: HEAT’S EFFECT ON WIND SYSTEMS

How does Earth’s rotation affect wind patterns? Earth rotates on its axis once each day. At the equator, Earth’s circumference is 40,079 kilometers. The day is 24 hours long, so the rotational speed is 1,670 kilometers per hour. Near the poles, Earth’s circumference is much smaller, so the speed also decreases, to about 290 kilometers per hour. Rotational speed affects air circulation. Air moves from an area of high pressure to an area of low pressure. High pressure comes from cooler air sinking toward the ground. Low pressure comes from warm air rising from the ground. The movement of air from high to low pressure is known as wind. The rotation of Earth deflects the wind from a straight line. In the northern hemisphere, wind is deflected to the right. In the southern hemisphere, wind is deflected to the left. Strong winds are deflected more than weak winds. The force responsible for the deflection is called the Coriolis effect.

Try Now Try this experiment to see how the Coriolis effect works: Materials • Piece of cardboard • Scissors • Ruler • Marker Directions • Cut a large circle from the cardboard. This represents Earth. Make a dot in the center of the circle to represent the North Pole. • Using a ruler and a marker, draw a straight line from the center of the cardboard to one edge. • This will represent wind direction unaffected by Earth’s rotation. • Slowly turn the cardboard counterclockwise. • While turning the cardboard, use the ruler and marker and try to draw a straight line from the center of the cardboard to the edge. This will represent the winds moving from the North Pole to the equator. Examine the line you have drawn. Questions: 1. Is the first line you drew straight? 2. Is the second line you drew straight? 3. What does this show about the wind’s path? 4. Does the wind’s path really change?

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STEMscopedia: HEAT’S EFFECT ON WIND SYSTEMS

What Do You Know? There are two types of wind systems: global and local. Global wind systems are created as a result of Earth’s rotation, the Sun’s heat, and Earth’s shape. They are large air masses. Local wind systems are those that are created from water bodies, mountains, vegetation, or other scenery. They change frequently and drive our weather forecasts. They differ from global wind systems because they cover short distances. Look at the examples below. Write either “global” or “local” next to the example of wind.

Sea breeze ______________

Mountain breeze ______________

Polar easterlies ______________

Ocean breeze ______________

Tropical easterlies _______________

Doldrums _______________

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STEMscopedia: HEAT’S EFFECT ON WIND SYSTEMS

Connecting With Your Child Your child has learned that heat and sources of heat affect weather patterns. All storms are formed from unequal heating of land and water with unstable air masses. When conditions change, it is usually due to the Sun and how it affects wind and water energy. To test temperature as it relates to air pressure, try this experiment. What do you think will happen when one balloon is cooled, one is kept at room temperature, and one is placed in a warm area? Materials • Balloons • Tape measures • Ice • Heat source Directions 1. Blow up the three balloons to the same size and tie them shut. 2. Measure the circumference of the balloons using a tape measure and record the measurements. The circumference is the distance around the outside of the balloon. 3. Use a marker and label the balloons 1, 2, and 3. Mark the balloons where they were measured and be sure to measure in the same place later. 4. Put balloon 1 in an ice bath for 10 minutes. Put a thermometer in the ice with the balloon. Record the temperature after 10 minutes. 5. Keep balloon 2 at room temperature. Record the room temperature after 10 minutes. 6. Balloon 3 should be put in a warmer area, like a sunny window, for 10 minutes. What other places can you think of to warm a balloon? A heat lamp? A small heater? Record the temperature in the area you choose after 10 minutes. 7. After 10 minutes, record the temperature and measure each balloon again. Measure each balloon at the same spot as originally measured. Be sure to measure right after removing the balloons from the ice bath and the warm area. Record the information. 8. Let all the balloons stay at room temperature for 5 minutes. 9. Measure the circumference of each balloon again. Record the measurements. • • • • • • •

What happened to the circumference of the balloon in the ice bath? The balloon in heat? Did any air escape from any of the balloons? What do you think happened to the air inside the balloons in each case? What does this experiment tell you about warm and cold air masses? Which type of air mass is denser (warm air or cool air)? Which type of air mass takes up more space (warm air or cool air)? Which has the greatest air pressure (warm air or cool air)?

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6E4C Heat’s Effect on Wind Systems

Reading Science Name:

Date:

Group:

Windy World “Listen closely to the wind … It is the sound of leaves in the trees, dancing and writing beautiful poetry across the sky.” 1.

A scientific definition may not be as romantic as a poetic definition, but it helps clarify what wind is. Wind is defined simply as the horizontal movement of air over Earth’s surface. There are different types of winds—a variety of local wind patterns and global wind patterns. What creates wind? Air moves as a result of differences in pressure between neighboring air masses. The greater the difference in pressure, the faster the wind speed will be. How does unequal heating of Earth’s surface create areas of high pressure and low pressure? Different matter on Earth’s surface absorbs the Sun’s radiation differently and heats up at varying rates. For example, a black tar street heats up more rapidly than a lake. When air is heated, the particles speed up and expand, causing warm air to be less dense than surrounding air. Less dense air rises. Where air is rising, the air pressure pushing down lessens, causing it to be a low-pressure area. Air from neighboring high-pressure areas rushes to the low-pressure area. In addition, after the rising warm air travels high enough, it cools and becomes denser. It then sinks and causes a high-pressure area. This cycle of rising low-pressure air and sinking high-pressure air causes convection, which causes wind. These convection patterns can happen locally or globally.

Beaches tend to be especially windy areas. Daily sea breezes and nightly land breezes at the coast are an example of local wind patterns in practice. Sand heats up and cools down more quickly than water. During the day, sand heats up rapidly, causing the air above it to rise and create a low-pressure area. The air above the ocean is a high-pressure area, so it rushes in from the ocean to the low-pressure zone above the sand. It is a sea breeze! At night, the opposite process occurs. Once the Sun sets, sand cools quickly while water cools at a slower rate. The air above the sand becomes cooler than the air above the water, so it sinks and becomes a high-pressure area. The air over the water remains warm and rises, becoming the low-pressure region. The direction of the convection is reversed as air rushes from the beach out to sea. It is a land breeze!

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Reading Science 3.

If sea breezes and land breezes are a local wind pattern, what happens on a global level? Convection still plays a major role, but on a much larger scale. On Earth, where do the Sun’s rays hit most directly and create the warmest air? The air above the equator is warm and less dense, so it rises. What parts of Earth receive the least amount of direct sunlight? The polar regions possess the coldest, densest air. The wind patterns on Earth would be simple patterns of convection (just like land breezes and sea breezes) except that Earth is a rotating sphere. The warm, rising air from the equator does not reach the poles. When Earth rotates, the rising air from the equator bends to the right and moves clockwise in the northern hemisphere while it bends to the left and moves counterclockwise in the southern hemisphere. This bending of air due to Earth’s rotation is called the Coriolis effect.

There are three prominent global wind patterns on Earth: trade winds, prevailing westerlies, and polar easterlies. All patterns are present in both the northern and southern hemispheres as mirror images of each other from the equator. What causes each pattern?

Trade winds are located between the equator and 30°N or 30°S. The warm equatorial winds rise and move toward the poles, but then cool and sink around 30° north or south. Then they flow back to the equator. The Coriolis effect causes them to flow toward the southwest in the northern hemisphere and toward the northeast in the southern hemisphere.

Where the air sinks at about the 30°N or 30°S point, a high pressure situation is set up. The air in both hemispheres migrates away from high pressure toward low pressure around the 60°N or 60°S point. In the northern hemisphere, the winds move toward the northeast, while in the southern hemisphere, they travel to the southeast. These winds are named prevailing westerlies because they blow from the west to the east. Why do the winds flow east when it seems to contradict the motion of Earth’s rotation? A complex combination of the Coriolis effect, cyclones, anticyclones, and deflection of winds due to differences in air pressure cause the prevailing westerlies. Most of the United States is located between the 30°N and 60°N latitudes, so our weather patterns tend to move west to east.

Polar easterlies received their name because they blow from the east. When air above the poles cools, it creates a high-pressure area, causing winds to flow away from it. Again, winds are bent by the Coriolis effect—from the north pole, it bends toward the southwest, and from the south pole, it bends toward the northwest.

Whether wind patterns are global or local, wind is everywhere. It is a valuable resource for energy, transportation, and recreation. Lucky for us, we live in a windy world!

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Reading Science 1.

What is the Coriolis effect? A

The rising of warm air, causing low pressure

The falling of cool air, causing high pressure

The bending of wind because of Earth’s rotation

Local convection currents that occur at the coast, causing sea and land breezes

Which of these factors causes wind to form? A

Earth’s revolution

Differences in air pressure

The Coriolis effect

Precipitation

Which of the following human activities throughout history probably depended the most on wind patterns? A

Merchants sailing different routes to get to various countries

Astronomers observing stars and planets

Farmers planting and harvesting crops

Engineers designing and constructing buildings

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Reading Science 4.

What does the word convection (paragraph 1) mean? A

Radiant heat from the Sun

Transfer of heat through the rising and sinking motions of liquids or gases

The forming of a cloud through cooling of warm water vapor

Converting liquids to gases

What causes windy conditions at the coast in the summer? A

Trade winds

The Coriolis effect

Windchill

Uneven heating of sand and water

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6E4C Heats Effect on Wind Systems

Math Connections Name:

Date:

Group:

The Sun’s radiation transfers thermal energy to the surface of Earth. Some reasons why the Earth’s surface is heated unevenly are: • The land and ocean absorb heat and warm up at different rates • The Earth’s rotation causes day and night • The shape of the Earth causes the Sun to heat the equator more directly than the poles The data below is from an investigation designed to test how well land and water absorb and retain heat. For 10 minutes, students placed a beaker of potting soil and a beaker of water under a light source. They measured and recorded the temperature in one-minute intervals. For the next 10 minutes, the light source was turned off and the temperature was recorded in one-minute intervals while the substances cooled. Time (minutes)

Temperature Temperature of Soil (°C) of Water (°C)

Time (minutes)

Temperature Temperature of Soil (°C) of Water (°C)

20.3

20.4

27.3

22.1

21.2

20.4

26.4

22.3

21.9

20.6

25.9

22.4

20.8

24.9

22.4

23.2

20.8

24.1

22.3

24.6

20.8

23.6

22.3

25.0

21.1

23.0

22.1

25.3

21.2

22.3

22.2

26.2

21.4

21.7

22.3

26.9

21.9

21.6

22.2

27.3

22.1

21.2

21.9

Temp. Change

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Temp. Change

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Math Connections 1.

Use the data tables on page 1 to create a graph demonstrating the change in temperature of the soil and water during the 20-minute investigation. Key Soil

Water

Calculate the temperature difference of the soil and water during the heating and cooling periods and record your answer in the tables on page 1.

Which material heated up the fastest? _________________________________________

How does this relate to the temperature of the air above land and water during the day?

Which material took the longest to cool? _______________________________________

How does this relate to the temperature of the air above the land and water during the night?

If warmer air rises and cooler air falls, draw a diagram describing how the air moves over land and water during the day and at night. Day

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Night

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6E4C Heat’s Effect on Wind Systems

Writing Science Name:

Date:

Group:

LOOK

THINK Uneven heating and cooling as well as the rotation of Earth cause global wind systems. Pilots have to take these wind factors into account in order to fly and land a plane properly. WRITE Explain how the uneven heating and cooling of Earth’s surface and the rotation of Earth work together to cause local and global wind systems. Also explain the effect that would have on a pilot. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6th Grade Earth and Space Science

6E4D

Meteorological Events

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6E4D Meteorological Events

Student Journal Name:

Date:

Group:

Part I: Air Lift 1.

Write your prediction about what will happen if you hit the board.

Write your observations about what actually happened when you hit the board.

What is the surface area of the chart paper? _____________________________________

Air exerts approximately 14.5 lbs of pressure per square inch. How do you calculate the amount of air pressure that is pushing down on the chart paper?

When collecting weather data, air pressure is measured using a barometer. Look at the class barometer. What is the current air pressure?

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Student Journal Part II: High- and Low-Pressure Systems 1.

What is a high-pressure area? How is a high-pressure area represented on a weather map?

What type of weather is associated with a high-pressure area?

What is a low-pressure area? How is a low-pressure area represented on a weather map?

What type of weather is associated with low-pressure areas?

For each Map Set (A, B, and C), determine the best location to place one H and one L to locate the center of the high- and low-pressure systems shown on the satellite image. Then duplicate the placement on the corresponding outline map. Map Set A

How does the high-pressure area shown on Map Set A affect North Carolina weather conditions?

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Student Journal Part II: High- and Low-Pressure Systems, continued Map Set B

How do temperatures of the low-pressure area on Map Set B affect possible precipitation to that area?

Map Set C

Use the terms “high-pressure system” and “low-pressure system” to describe current weather conditions using Map Set C in North Carolina and on the east coast.

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Student Journal Part III: Four Types of Fronts Cold Fronts 1.

On the cross section diagram of the cold front below, leave the developing cloud system white, shade the ground brown, the cold air mass blue, and the warm air mass red.

Use the graphic and information from the Student Guide to explain why a band of heavy clouds form at the leading edge of a cold front and can cause intense storms that are usually of short duration.

Locate the cold front symbol and point A on the map. What are current weather conditions at point A?

Locate point B on the map. What are the current temperature and cloud cover conditions at point B?

Locate point C on the map. Compare the current temperature conditions between points B and C.

What will weather conditions be like at point C several days from now after the front passes? Explain why.

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Student Journal Part III: Four Types of Fronts, continued Warm Fronts 1.

On the cross section diagram of the warm front below, leave the developing cloud system white, shade the ground brown, the cold air mass blue, and the warm air mass red.

Use the graphic and information from the Student Guide to explain why bands of scattered clouds form at the leading edge of a warm front and can cause continued showers for several days.

Locate the warm front symbol and point A on the map. What are current weather conditions at point A?

Locate point B on the map. What are the current weather conditions at point B?

Locate point C on the map. How will weather conditions change at point C on the map in the next day or two? Explain why.

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Student Journal Part III: Four Types of Fronts, continued Stationary Fronts 1.

On the cross section diagram of the stationary front below, leave the developing cloud system white, shade the ground brown, the cold air mass blue, and the warm air mass red.

Use the graphic and information from the Student Guide to explain why clouds and precipitation occur at a stationary front and can linger.

Locate the stationary front symbol and point A on the map. What are current weather conditions at point A?

Locate point B on the map. What are the current weather conditions at point B?

What will weather conditions likely be two days from now at point A and point B on the map? Explain why.

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Student Journal Reflections and Conclusions 1.

What three factors influence our day-to-day weather?

What type of heat transfer is most common in our atmosphere? Explain.

What is air pressure?

Describe a high-pressure air system and resulting weather conditions.

Describe a low-pressure air system and resulting weather conditions.

Fill in the data table based on the four types of fronts. Type of Front

Map Symbol

Resulting Weather Conditions

Cold Front Warm Front Stationary Front Occluded Front

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STEMscopedia: METEOROLOGICAL EVENTS 6E4D Reflect Do you ever wonder what causes a tornado or why the wind blows and the clouds swirl in a thunderstorm? Does your parent check the weather to see what the temperature and meteorological activity are going to be for that day or the next week? Does any of the weather remind you of what Dorothy went through in The Wizard of Oz? If you’ve ever seen a tornado or thunderstorm, you realize that the weather can be very unpredictable. A tornado touches the ground, goes back up, and travels several miles, spinning the whole way and picking up whatever is in its path. Or it can hail on one side of the highway and just rain on the other, with the wind and clouds swirling. These types of weather occur all over the planet, depending on air masses, fronts, and the air pressure.

How do weather events occur? Without the Sun, Earth would not experience weather as we know it. The Sun’s radiation brings with it energy in the form of heat. Water and land absorb heat and warm up at different rates. Some of the energy is transferred from Earth’s surface to the gases in Earth’s atmosphere through convection. Convection currents in the atmosphere refer to the flow of air in circular patterns. Air rises, flows parallel to Earth’s surface, falls, flows parallel to Earth’s surface, and rises again. What causes the air to move like this? Convection Currents The ground heats up as it absorbs sunlight, warming air near Earth’s surface. As this air heats up, it becomes less dense than the cooler air above. This causes the warm air near Earth’s surface to rise. As warm air rises, the denser, cooler air rushes beneath it. The cooler air sinks toward the ground, where it also becomes warmer. Eventually, it becomes less dense than the air above it and begins to rise. As this cycle repeats itself, convection currents form.

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STEMscopedia: METEOROLOGICAL EVENTS Precipitation As air warms and cools, water in the air changes from gas (water vapor) to liquid (water droplets) and solid (ice). These phase changes produce other weather events. Heat near Earth’s surface causes liquid water to evaporate from oceans, lakes, and rivers. As the water vapor rises and cools, it condenses to form clouds of water droplets or ice pellets. When the clouds become too heavy to ﬂoat, the water falls back to Earth as precipitation in the form of rain, snow, or hail.

Air Masses Air masses are large bodies of air that have similar temperature and moisture properties. They can cover very large areas. What happens when two air masses meet? The cold air pushes the hot air up. As the hot air goes up, the temperature drops, and the air can’t hold as much water as it does when it is warm, so the cold water molecules condense and form clouds. Fronts The boundary between two air masses of different humidity and temperature is called a front. With a cold front, cold air displaces warm air. A warm front means warm air displaces cold air. A stationary front occurs when neither air mass displaces the other. Intense storms and large, tall clouds may form along cold fronts. A warm front would be accompanied by widespread clouds, rain, snow, sleet, or drizzle.

Air Pressure Air pressure is the weight of a column of air over a certain location on Earth. Air masses that are denser apply greater pressure because they contain more particles of air per unit volume. Each type of air mass is linked with certain kinds of weather. On a weather map, air pressure is shown or labeled with “high” or “H” for high pressure air masses and “low” or “L” for low pressure air masses.

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STEMscopedia: METEOROLOGICAL EVENTS Look Out What causes thunderstorms? Unstable air masses cause thunderstorms. Thunderstorms occur when rising warm, humid air meets sinking cooler air quickly. The air mass creates a tall towering cloud. At the top of the towering cloud, where it is near freezing, ice particles will begin to bounce off each other. This is what causes the electric charges that we see as lightning. Thunderstorms occur more often in the spring and summer months. What causes tornadoes? Tornadoes are windstorms that have swirling winds that spin at incredible speeds of up to 400 miles per hour. Tornadoes are caused by severe low-pressure zones that cause forceful winds. Tornadoes usually form from very powerful thunderstorms. Tornadoes are difficult to predict and often strike without warning. They are nature’s most violent storms. Misconceptions: MYTH: You should always open a window in your home to equalize the pressure to prevent your house from exploding. TRUTH: Houses do not explode when a tornado passes over them. Taking time to open a window might prevent you from finding a safe place. MYTH: It is easy to outrun a tornado in your vehicle. TRUTH: Tornadoes often reach speeds of 70 miles per hour. Leave your vehicle and find safe shelter. MYTH: Tornadoes do not travel or form over water. TRUTH: Tornadoes can cross over rivers and streams. Tornadoes that form over water are called “waterspouts.”

What Do You Think? Scientists who study the weather and monitor weather conditions are called meteorologists. They use satellite images to map out where large air masses are located on Earth. Meteorologists also use scientific principles to explain, research, predict, and understand what is going on in the atmosphere. Using the principles they studied, it would seem that the weather you see on television is always right. Since meteorologists have no control of the atmosphere—including fronts, air masses, or air pressure—the weather can change at any time. Sometimes weather predictions can be wrong. There is the chance that weather conditions will act in an abnormal way. Geographic features also affect weather. Mountains and large bodies of water can affect and influence the weather in your local area. If you live on a coastline, the temperature near the ocean may be higher than the temperature inland. Match the weather terms and definitions.

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STEMscopedia: METEOROLOGICAL EVENTS What Do You Know? ___Air mass a. The boundary between two air masses of different humidity and temperature. ___Fronts b. Caused when rising warm, humid air meets sinking cooler air. ___Tornadoes

c. The weight of a column of air over a certain location on Earth.

___Thunderstorms d. Large bodies of air that have similar temperature and moisture properties. ___Air pressure e. Windstorms that have swirling winds and spin at incredible speeds of up to 400 miles per hour. ______________________________________________________________________

Connecting With Your Child To improve your child’s understanding of these concepts, try the following investigations. Convection Currents Materials: • 1 Wide-mouth jar (quart-sized) • 1 Microwave-safe cup • 1 Eyedropper • 2¼ Cups water • Blue food coloring Place two cups of cold water in the wide-mouth jar. Let it sit without moving it for 5 minutes. Heat onequarter cup of water in a microwave-safe cup until steam forms. Color this water blue. Using an eyedropper, place an eyedropper full of blue water in the bottom center of the jar and release it into the cold water. The warm water currents will rise to the top due to convection.

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STEMscopedia: METEOROLOGICAL EVENTS Materials: 1-liter plastic water bottle Any color food coloring 1 Alka-Seltzer® or fizzy tablet ¾ Cup water ¼ Cup vegetable oil 1 Flashlight If you have a lava lamp, turn it on and watch the “lava” move up and down as it cools and heats. You can also make your own lava lamp. Fill the 1-liter plastic water bottle with three-quarters cup of water. Add the vegetable oil until the bottle is almost full. Put 10 to 15 drops of food coloring in the bottle and add half Alka-Seltzer® tablet or fizzy tablet. Then watch what happens. Put a flashlight under the bottle to make it look like a real lava lamp. This is also convection. Tornadoes Materials: • 1 clear plastic water bottle • Food coloring (any color, though neon is cool) • 1 bottle liquid dish soap • Tap water • Mason jar with lid (optional) Fill three-quarters of the clear plastic water bottle with tap water. Color the water with your chosen food coloring. Add two to three drops of any liquid dish soap. Put the lid back on the water bottle tightly. Spin the bottle very quickly upside down. When you stop, you will see a tornado in the bottle spinning. Discuss what is happening with your child. This can also be done with a Mason jar with a lid. Follow the same steps, but be careful because this jar is glass.

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Reading Science Name:

Date:

Group:

Tornadoes 1.

Have you ever seen The Wizard of Oz? A twister blows across Kansas farmland. It picks up Dorothy’s farmhouse and drops it in a magical land. Although the movie is fantasy, the tornado is somewhat realistic. The dark clouds, high winds, and erratic path of the tornado are true characteristics of tornadoes.

What is a tornado? It is a funnel-shaped, rapidly rotating cloud. One end touches the ground, and the other end finishes in a cumulonimbus cloud. Tornadoes are violently destructive parts of some storm systems. Compared to thunderstorms and hurricanes, tornadoes are relatively small. The average size of a tornado is 100 meters in diameter; the average diameter of a hurricane is about 600 kilometers. Twisters are fast and furious—they often do not exist for more than 10 minutes. With wind speeds between 180 km/h and 480 km/h, a tornado can do tremendous damage to anything in its path.

How do tornadoes form? They form as part of thunderstorms and low-pressure systems called super cells. A super cell occurs because of convection. Warm air rises quickly from the ground in what is called an updraft. When warm air reaches the top, the temperature drops rapidly and causes condensation. A giant cumulonimbus cloud forms. When little droplets of condensation become large drops, precipitation falls. It drags cold air down from high in the atmosphere. How does a tornado form from this process? When updrafts occur at high speeds, winds may begin to rotate. If winds spread downward and the winds narrow, a funnel cloud forms. When the column of whirling air from the cloud has one end on the ground, it is called a tornado.

Where and when are tornadoes likely to form? Every continent except Antarctica experiences tornadoes. However, many tornadoes occur in “tornado alley,” an area in the Great Plains. It includes parts of Texas, Oklahoma, Kansas, South Dakota, Iowa, Illinois, Missouri, New Mexico, Colorado, North Dakota, and Minnesota. Tornadoes occur throughout the year, but most happen in the spring. They often happen between 3:00 p.m. and 9:00 p.m., when conditions are ripe for producing super cells.

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Reading Science 5.

How is the destruction caused by tornadoes measured? Scientists use the Fujita scale. It rates tornadoes based on the damage they cause to buildings and natural vegetation. Tornadoes are rated from F0 to F5. F0 tornadoes have wind speeds around 100 km/h and break branches off trees. F5 tornadoes cause incredible devastation. F5 tornadoes possess wind speeds up to 500 km/h and carve out paths of destruction 1.5 km wide. They destroy sturdy buildings, relocate large houses, and toss cars into the air. Fortunately, F5 tornadoes make up only about 0.1% of tornadoes.

One of the most powerful and destructive tornadoes ever was the Great Tri-State Tornado, which tore through Missouri, Illinois, and Indiana on March 18, 1925. An F5 tornado, it was on the ground for 3.5 hours, and traveled over 350 km. Wind speeds most likely reached 500 km/h.

Tornadoes are a commanding force of nature. Meteorologists study tornadoes in an attempt to learn what causes them and how they will behave once they have formed. When scientists better understand tornadoes, they can help protect people and property from damage inflicted by these powerful natural disasters.

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Reading Science 1.

What does the Fujita scale measure? A

The size of tornadoes

The speed of tornadoes

The damage caused by tornadoes

How long tornadoes are on the ground

Which city is located in tornado alley? A

Los Angeles, California

New York, New York

Seattle, Washington

Oklahoma City, Oklahoma

What is an updraft? A

Rapidly rising warm air

Rapidly rising cool air

Minor league ball players being called up to the major leagues

A tornado

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Reading Science 4.

Which of the following is NOT a reason meteorologists research tornadoes? A

To predict when tornadoes will form

To give people more time to get to safety

To better predict the paths of tornadoes

To develop faster vehicles with which to chase tornadoes

What is the best summary of this passage? A

The Great Tri-State Tornado was the most powerful and deadliest tornado in history.

Tornadoes are intense, destructive funnel clouds that meteorologists study to try to help protect people and property.

Tornadoes are funnel-shaped clouds that occur on all continents except Antarctica.

Tornadoes are storms that occur mostly in the spring in tornado alley.

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Math Connections Name:

Date:

Group:

Ocean currents drive weather patterns. Currents bring warm air toward the poles, where it cools and bring cool air back toward the equator. The surface currents are measured by the number of cubic meters that are being transported per second. This is measured in a unit called sverdrup (sv), which equals 1,000,000 m³. Surface currents are considered to be currents at -400 meters (m) or higher of the ocean’s surface. 1.

Describe what the passage means by -400 m or higher.

What would be considered 0?

Located on the east coast of continents are western boundary currents which move about 450 kilometers (km) a day at a rate of 57 sv. a) How long would it take for the current to move 2700 km? (450 km/day = 2700 km/x days). X = 2700/450 = ______.

b) How many meters cubed (m3) were moved? (1 sv = 1,000,000 m3 ; 57 sv = 57,000,000 m3 ) 6 x 57,000,000 = ________________m3

Located on the west coast of continents are eastern boundary currents, which move about 34 km a day at a rate of 13 sv. a) How long would it take for the current to move 2700 km? (Round to the nearest whole number.)

b) How many m3 were moved?

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Math Connections Maria is studying the effect of mountains on climate. She starts at the coast and climbs the mountain over the course of many days. She takes many measurements and descends on the far side, called the lee side. Use the information above to answer questions 5-9. 5.

She goes higher and higher and records temperatures that get consistently lower and lower. She records the following temperatures: 98º, 71º, 57º, 40º, 12º, 1º, 8º, 10º, 12º, and 15º. She realizes she recorded the number incorrectly. Explain what is missing in the data.

Why is the missing part of the data so important?

She also records her height compared to sea level. She records her height to be 10,000 ft, 13,500 ft, and 23,000 ft. Should these numbers be positive or negative? Why?

From 23,923 ft, she descends on the lee side of the mountain into a valley. She calculates her height compared to sea level, which is 10 ft below sea level. How far did she descend? (The -10 ft below sea level is added to total descent level).

Maria meets with a student, Jack, and gets into a heated argument. Jack reviews Maria’s conclusion that there is less than 1 inch of rainfall on the lee side of the mountain each day and says, “So, there is a negative amount of rain on the lee side of the mountain.” Explain in detail why Jack is incorrect.

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Writing Science Name:

Date:

Group:

LOOK

THINK Think about the effects air pressure, fronts, and air masses have on weather systems and how meteorologists use that information to make predictions. WRITE Explain how a meteorologist studies air pressure, fronts, and air masses to predict future weather systems. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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Writing Science

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6th Grade Earth and Space Science

6E4E

Moisture and Weather Patterns

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6E4E Moisture and Weather Patterns

Student Journal Name:

Date:

Group:

Part I: Cloud Types Card Sort 1.

Use the chart below to fill in the information from the cloud types card sort.

Type of Cloud

Associated Elevation

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Sketch

Shape Description

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Student Journal Part II: Weather Maps

The weather map above represents the weather for today. Use it to predict the weather for the next two days in your part of the state.

Where would you go to find the coldest spot in the United States? Explain.

If you were planning a vacation to Disney World in Florida in three days, what kind of weather should you expect?

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Student Journal Part III: Comparing Satellites and Radar 1.

What do satellite images and radar have in common in regards to predicting weather?

How do satellite images and radar differ in regards to predicting weather?

What is one benefit of radar in predicting weather?

What is one benefit of satellites in predicting weather?

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Student Journal Reflections and Conclusions 1.

How does knowledge about clouds help predict weather?

What tools do meteorologists use to predict weather?

How has technology helped advance weather predicting?

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Reflect Earth is often called the “blue planet” because so much of its surface (about 70%) is covered by water. Of all the water on Earth, about 96.5% is held in the world’s oceans. As you can imagine, these oceans greatly influence our environment, including daily and long-term weather patterns. Most people associate weather with the atmosphere. How do oceans relate to weather and the atmosphere? Solar Radiation, Convection Currents, and Wind Currents The Sun is the driving force behind our weather, but our oceans play a major role in Earth’s weather patterns. Earth absorbs energy called solar radiation from the Sun. Some of the energy is transferred from Earth’s convection: transfer of surface to the gases in Earth’s atmosphere through convection. As thermal energy in a fluid the gas molecules warm up, they become less dense and rise farther such as air or water; warm into the atmosphere, helping to distribute heat. The gas molecules air rises and cold air sinks higher in the atmosphere cool, becoming denser. These molecules sink toward Earth’s surface. This rising and sinking of warm and cool air creates convection currents in the atmosphere. We refer to these convection currents as wind. Different areas of Earth’s surface absorb various amounts of solar radiation. This results in temperature differences in the atmosphere. For example, during the day, land heats up faster than oceans. So above land, warm air is less dense, resulting in an area of low pressure. The warm air over land rises, while the cooler air over oceans sinks, creating wind currents. Wind moves from high-pressure areas to low-pressure areas, so winds blow toward the coast. This is illustrated in the diagram.

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In contrast, during the night, land cools faster than oceans. Therefore, the warmer air above oceans rises, while cooler air over land sinks. Winds blow away from the coast. This is shown in the Low to High diagram. Earth’s rotation also influences wind currents by deflecting wind as it moves over Earth’s surface. Wind currents in the northern hemisphere are pushed to the right. Wind currents in the southern hemisphere are pushed to the left. This deflection of wind by Earth’s rotation is called the Coriolis effect.

What Do You Think? Look at the map of Texas at the right. Which areas do you think tend to experience more breezes? Explain your reasoning. Ocean Currents In addition to circulating energy through the atmosphere, wind also influences ocean circulation. As wind blows along the surface of oceans, some surface water moves along with it. This creates ocean currents that move energy from the tropics (near the equator) to the poles. For example, wind is responsible for the Gulf Stream that moves warm, less dense surface water from the tropics, north along the eastern coast of the United States, and all the way to Europe. Temperature and salinity both affect ocean currents, particularly in deep areas of the ocean. This is because temperature and salinity affect water density. Warm water is less dense than cold water. Also, freshwater is less dense than salt water. Water temperature and salinity vary with location. The thermohaline circulation is a major, deep ocean current that moves energy from the tropics to the poles. The Gulf Stream is part of this circulation. Recall that the Gulf Stream moves warm surface water from the tropics to the north. As this occurs, the heat energy in the water is transferred to the air. As the The blue lines in this image water moves northward, it becomes cooler and denser, and sinks. This show the movement of cold cold, dense water then flows back toward the equator. ocean currents, and the red lines show the movement of warm ocean currents. Oceans play a vital role in regulating global climate and weather patterns. When warm ocean water flows into an area, some of the water evaporates, transferring thermal energy to the atmosphere. Rising water molecules cool and condense to form clouds. The increase in water vapor raises the humidity in the area, and the transfer of thermal energy raises the temperature. 264

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The opposite is true when cold ocean water flows into an area. The cold water absorbs thermal energy from the surrounding atmosphere, causing water temperature to decrease. When the temperature decreases, there is less evaporation and therefore less humidity.

evaporate: to change from a liquid to a gas condense: to change from a gas to a liquid

Hurricanes Recall that solar radiation warms ocean water, causing some of the water to evaporate. As the water molecules rise, they cool and condense, forming clouds. If enough water condenses in these clouds, it will become too dense for the atmosphere to hold. This causes the water to fall from the sky as precipitation. When warm ocean water evaporates very quickly over a widespread area, clouds can form so rapidly that they result in large storms such as hurricanes.

Look Out Hurricanes are violent storms that form when large amounts of ocean water evaporate. The rapid evaporation and rise of water vapor pulls air away from the surface of the ocean water. This void of air leaves an area of low pressure underneath the mass of rising air. An imbalance with the surrounding atmosphere causes other air masses to be drawn into this low-pressure zone. This air warms up and rises too. The pressure gets lower and lower beneath the rising air as more and more warm ocean water evaporates and rises. As the cycle continues and air continuously rushes into the lowpressure area, the system begins to spin with the movement of air.

In this photograph of a hurricane, the eye is a dark spot in the center of the storm. Although winds are calm in the eye, the area surrounding the eye is the most intense part of a hurricane.

Eventually, the air rises high enough in the atmosphere and cools. The water vapor condenses and forms massive clouds. These clouds continue to spin with the rest of the system. Because there is so much moisture in the system, much of the condensation will lead to heavy rain. The differences in temperature and pressure result in so much air movement that wind speeds become very high. The temperature of the water and the rate of evaporation generally determine the size of the storm. The warmer the water, the faster it will evaporate, and the stronger the hurricane will be.

Hurricanes cannot form over land because they are fueled by warm, tropical water. However, ocean currents can push the water that forms the hurricane along the coast. After the hurricane has formed, atmospheric winds can push the hurricane over the land. Once the hurricane moves over land, it no longer has a continuous supply of evaporating sea water. The hurricane will slowly die out, but not before causing significant damage to the area over which it passes. The intense wind and rainfall can knock down trees, cause flooding and power outages, and damage homes and other buildings. Are hurricanes more likely to form near the equator or near the poles? Explain your reasoning.

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What Do You Think? Looking to the Future: Global Warming and Storms According to the Intergovernmental Panel on Climate Change (IPCC), there has been a 0.6 degree Celsius increase in Earth’s average global temperature over the past 110 years. Many scientists believe that this global warming trend has resulted from a combination of natural causes and air pollution released by the burning of fossil fuels. Natural causes include changes in solar radiation, which varies over an 11-year cycle. However, there has been a gradual but steady increase in solar radiation since the early 1700s. This means that Earth has been continuously retaining slightly more solar radiation, causing slightly more warming over the past few centuries. The IPCC believes this gradual increase in solar radiation could be responsible for up to half of the 0.6 degree increase in Earth’s average global temperature. The increase in solar radiation means that there is more radiation that can be absorbed by Earth. Some solar radiation is immediately reflected by Earth’s atmosphere and surface back into space. The rest is absorbed by Earth’s surface, warming it up. Eventually, this heat is radiated back out into space. There must be a balance between incoming and outgoing solar radiation. Otherwise, Earth would become too hot to support life as we know it. Some gases in Earth’s atmosphere block thermal energy from escaping back into space. These are called greenhouse gases. Greenhouse gases include carbon dioxide, methane, and other gases that are released by the burning of fossil fuels. Many of these gases are naturally found in the atmosphere. However, since humans began burning large quantities of fossil fuels, the amount of greenhouse gases in the atmosphere has increased. This disrupts the natural balance of incoming and outgoing solar radiation by preventing some radiation from escaping Earth’s atmosphere. Many scientists believe that this imbalance has contributed to the increase in the average global temperature. Furthermore, an increase in absorbed solar radiation could theoretically lead to more frequent storms like hurricanes. fossil fuels: fuels formed over millions of years from dead plants and animals; coal, oil, and natural gas are fossil fuels

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Greenhouse gases, indicated by the gray curvy line, can block some solar radiation. This radiation then bounces back to Earth.

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Try Now What do you know? Oceans greatly influence Earth’s weather and climate. Read each statement in the top row of the chart below. Then decide whether you agree or disagree with the statement and explain your decision. In Texas, a city that is far inland is typically cooler and drier than a city near the Gulf of Mexico.

Alaska is Ocean currents surrounded by move cold water cold water, so the from the tropics to state experiences the poles where more hurricanes the water warms. than most areas of the United States.

Hurricanes lose energy as they make landfall.

Agree or Disagree? Why?

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Agree or Disagree? Why?

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Connecting With Your Child Experimenting With Water and Weather To help your child understand how the oceans influence Earth’s climate and weather, try conducting a few simple experiments together. Evaporation from warm water transfers thermal energy to the atmosphere, causing the water vapor and warm air to rise. When they move higher into the atmosphere, these gases cool and condense to form clouds. This can be demonstrated by a simple experiment at home. First, gather the following items: • A clear glass jar • A pot • Some water • A metal can with a base large enough to completely cover the mouth of the glass jar • A few ice cubes • A flashlight Boil some water and pour it into the jar, filling it up only 1-2 centimeters. Put the ice cubes in the metal can, and place it on top of the glass jar. Turn off the lights or bring the jar and can into a dark room. Instruct your child to shine the flashlight on the jar. Watch for several minutes as the steam from the hot water rises to the top of the jar, then cools and condenses as it approaches the ice, forming a small cloud inside of the jar. Next, perform an experiment to help your child understand the manner in which the Coriolis effect influences wind and ocean currents. First, gather the following items: • A light-colored balloon (yellow works best) • A permanent marker Blow up the balloon and tie it shut. Slowly rotate the balloon in a clockwise direction and instruct your child to slowly draw a straight line from the center of the balloon toward its top as you continue to rotate the balloon. Once your child has drawn the line toward the top of the balloon, examine the path of the line across the balloon. Your child drew the line straight from the center to the top, but because the balloon was rotating, the line was deflected to the right. Here are some questions to discuss with your child as you conduct and complete each experiment: • Why does the steam rise to the top of the jar? • Why does the cloud form inside the jar? • How does this experiment relate to how warm ocean water creates clouds in Earth’s • atmosphere? • How does the rotation of the balloon affect the direction of the line you drew? • How does this experiment relate to the way the Coriolis effect influences wind and ocean • currents?

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Reading Science Name:

Date:

Group:

Hurricanes 1

It all starts out at sea. Warm ocean water and warm, moist air swirl together in a deadly dance. These conditions can turn a mild thunderstorm into a powerful hurricane. This is how a destructive force of nature is born.

Hurricanes start out as small disturbances in the air over warm tropical ocean water. This can happen in the southern Atlantic Ocean, the Gulf of Mexico, the Caribbean Sea, and the Pacific Ocean. Heat from the ocean water warms the air above it. Evaporating sea water gives energy to the growing storm. These huge storms can bring heavy rainfall, giant waves, and powerful winds to the land in their path. Hurricanes can have winds that range from 75 miles per hour to 200 miles per hour. The center of a hurricane is the area of lowest air pressure. This center is called the hurricane’s eye. It is the calmest part of the storm, with surprisingly still air and no clouds. The storm swirls around the eye, rotating counterclockwise in the northern hemisphere.

Hurricane season usually starts in the beginning of June and lasts until the end of November. Some years many storms develop, and other times only a few storms form. Year after year, these violent storms have made their way to shore causing death and destruction. They not only affect the coastline, but continue inland, often causing flooding and wind damage all along their path.

One such hurricane was Katrina, a huge storm that made landfall in New Orleans in August 2005. While not the strongest hurricane recorded in the United States, it was the most costly. Katrina was the deadliest hurricane in the United States since storms began receiving names in the 1950s. It caused major damage to the Mississippi, Alabama, and Louisiana coasts. Its impact was felt for 90,000 square miles. It caused more destruction than any natural disaster in the history of the United States. Hurricane Katrina’s 140-mile-per-hour winds brought storm surges and heavy rainfall. These storm surges had waves as high as 20 feet that crashed down on shore destroying buildings, homes, schools, cars, and trees. Sadly, the death toll reached nearly 2,000 people. Hurricane Katrina cost the United States approximately $75 billion in total damages. The impact of Hurricane Katrina can still be felt today as people rebuild their cities and their way of life. It changed the way that the United States looks at hurricanes forever.

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Reading Science Continued 5

Another devastating hurricane blew in right on Hurricane Katrina’s tail. Just one month after the destruction of Hurricane Katrina, Hurricane Rita made landfall in September 2005. This storm developed in the same area of the Atlantic Ocean that Hurricane Katrina did. Hurricane Rita quickly became the strongest hurricane of 2005, with wind speeds reaching 180 miles per hour. Cities and towns had just started to recover from the destruction of Hurricane Katrina. Once again, they faced high winds, storm surges, heavy rain, and tornadoes. In Texas, more than three million residents were evacuated, causing giant traffic jams for over two days. This was the largest evacuation in the United States’ history. Unlike Hurricane Katrina, Hurricane Rita only took the lives of 120 people. Only seven deaths were directly caused by the hurricane itself. This time, the damage was estimated at approximately $10 billion.

Hurricanes are a deadly force of nature. Scientists study hurricanes to understand more about what causes them. Scientists are also trying to learn how to give people more advanced warning to get to safety. Scientists believe that the average number of hurricanes per year is increasing. Hurricanes also seem to be increasing in strength. This may be a result of global warming or temperature changes deep in the Atlantic Ocean caused by natural environmental cycles. In either case, scientists predict that severe hurricanes will form more frequently in the future.

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Reading Science 1.

What conditions must be present for a hurricane to form? A

A thunderstorm that mixes with cool ocean water and cool, moist air allowing it to grow in size and strength

The same conditions that form a tornado

A thunderstorm that forms over warm ocean water

Heavy winds, torrential rain, and storm surges

Why can a hurricane cause so much destruction? A

Hurricanes have high winds with torrential rains, storm surges, and possible tornadoes.

Hurricanes move fast, destroying everything in their path.

When the eye of the hurricane reaches land, people think the storm is over when really they are just in the middle of it.

All forces of nature cause destruction.

Hurricane Katrina and Hurricane Rita are similar in what way? A

They began as small storms over the Atlantic Ocean.

They caused major damage to the Texas coast.

They had wind speeds of 140 miles per hour.

They caused the biggest evacuations in United States history.

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Reading Science 4.

Hurricane Katrina and Hurricane Rita are different in what way? A

Hurricane Katrina had a very large storm surge, while Hurricane Rita did not cause any storm surge.

Hurricane Katrina caused more death and destruction than did Hurricane Rita.

Hurricane Katrina was a much stronger storm than Hurricane Rita.

Hurricane Katrina made landfall in September 2005, and Hurricane Rita made landfall in August of 2005.

What is the best summary of this passage? A

Hurricane Katrina was the deadliest and most costly hurricane in United States history.

Hurricanes are destructive, but not as destructive as tornadoes.

Scientists are studying hurricanes to be able to better predict their formation and movement.

Hurricanes gain energy and develop over warm ocean water. Hurricanes can be costly in human lives, as well as in economic terms.

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Math Connections Name:

Date:

Group:

Hurricanes A hurricane is an extremely powerful storm with strong winds up to 200 miles per hour (mph). Hurricanes can be as large as the state of Texas and generally last a week or more. They form over warm ocean water because of the tremendous amount of energy available. A typical hurricane season starts June 1 and ends November 30. Hurricanes are categorized according to the SaffirSimpson scale, which evaluates hurricanes based on wind speed, damage, and storm surge. Category

Sustained Winds

Damage

Storm Surge

74-95 mph

Minimal: vegetation & signs, small/loose structures

4-5 feet

96-110 mph

Moderate: roofs, small boats, flooding

6-8 feet

111-130 mph

Extensive: small buildings

9-12 feet

131-155 mph

Extreme: roofs & mobile homes destroyed, beach homes flooded

13-18 feet

155+ mph

Catastrophic: most buildings destroyed, roads flooded

18+ feet

The year 2005 was a record-breaking season for hurricanes in the Atlantic Ocean for a variety of reasons: number of hurricanes in a season, deadliest season, most expensive season, and the most intense hurricane ever recorded. Look at the table below and then answer the questions regarding the data. Hurricane Name

Duration (in days)

Category

Cindy

Dennis

Emily

Irene

Katrina

Maria

Nate

Ophelia

Philipe

Rita

Stan

Vince

Wilma

Beta

Epsilon

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Math Connections 1.

What percentage of hurricanes in 2005 were category 5 hurricanes?

What percentage of hurricanes in 2005 were less than extreme?

What percentage of hurricanes lasted more than a week?

What percentage of category 5 hurricanes lasted more than a week?

What percentage of hurricanes in 2005 were category 1 hurricanes?

Which hurricane names might have been retired after the 2005 season? Why?

If there were seven major hurricanes out of the 28 tropical storms, what percentage of the storms were considered major hurricanes?

Look carefully at the 2005 hurricane data table. Construct a bar graph that shows the number of storms from each category during the 2005 Atlantic hurricane season. Be sure to include the title “2005 Atlantic Hurricane Season” and to label the horizontal axis “Hurricane Category” and the vertical axis “Number of Hurricanes.”

*After you are done creating your graph, write a question based on the data on your graph for a classmate to answer.

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Writing Science Name:

Date:

Group:

LOOK

THINK Think about types of severe weather. WRITE Explain how uneven heating and cooling of Earth’s surface causes major weather events, such as thunderstorms, tornadoes, and hurricanes. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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Writing Science

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6th Grade Earth and Space Science

6E5A

Layers of Earth

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Student Journal Name:

Date:

Group:

Part I: Modeling Layers Based on Chemical Composition Create a cross section diagram of Earth. Color the layers and the legend as you create the model.

Legend Crust Mantle Core

1. What is the chemical composition (or makeup) of most of the crust material? 2. Where is the crust found? 3. What is the chemical composition (or makeup) of most of Earth’s mantle material? 4. Why do you think the mantle materials sank lower toward the center of Earth’s gravity as compared to the crust materials? 5. What is the chemical composition (makeup) of Earth’s core? 6. Why do you think these core materials sank to Earth’s center? 7. Which layer makes up the majority of Earth’s interior? 8. Which layer is the thinnest when looking at a cross-section of Earth? 9. What characteristics or properties of Earth’s materials are used to classify layers as crust, mantle, and core? © Accelerate Learning Inc. - All Rights Reserved

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Student Journal Part II: Modeling Layers Based on State of Matter 1. What are three basic states of matter?

2. Which of the crust/mantle/core layers are located in the lithosphere?

3. What is the state of matter of the lithosphere?

4. Which layer classified based on chemical composition is found in the asthenosphere?

5. What is unusual about the asthenosphere’s state of matter?

6. Look at the model and think about a logical reason why the inner core is under more pressure than the outer core. What causes more pressure in the inner core?

7. What is a logical reason why the inner core’s state of matter (solid) is different from the outer core’s state of matter (liquid)? Hint: Look at question 6 above.

8. What characteristic or property of Earth’s material is used to classify layers as lithosphere or asthenosphere, as well as the inner or outer core?

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Student Journal Part III: Investigating Solids That Flow Asthenosphere Plasticity Model 1. Press down gently on your bag that represents the asthenosphere. When you first press down gently on the bag, what does it feel like?

2. Now, poke the bag quickly. How does the asthenosphere respond?

3. The asthenosphere layer is a solid with plasticity. How does this substance act like a solid?

4. How does the substance act like a liquid?

5. Think about the asthenosphere’s property of plasticity. How might the plasticity of the asthenosphere affect the layer directly above it, the lithosphere? How do you think the solid lithosphere and the flexible asthenosphere interact?

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Student Journal Reflections and Conclusions 1. The crust, mantle, and the overall core areas of Earth are classified and divided into layers based on

2. The lithosphere, asthenosphere, inner core, and outer core areas of Earth are classified and divided into layers based on

3. Which type, the three-dimensional clay half sphere or the two-dimensional cross section diagram, provides more advantages as a model? List the advantages of each in the space below. Advantages of: 3-D half sphere

2-D cross-section diagram

4. Which type, the three-dimensional clay half sphere or the two-dimensional cross section diagram, has more limitations as a model? List the limitations of each in the space below. Limitations of: 3-D half sphere

2-D cross-section diagram

5. Imagine the cool, solid lithosphere layer is cracked into pieces similar to the shell of a hardboiled egg. Do you think the pieces might move around on the flexible asthenosphere? Why or why not?

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STEMscopedia: LAYERS OF EARTH 6E5A Reflect How many layers is the Earth composed of? What role does density play in how the layers are formed? How does temperature affect the layers? The Earth is composed of four layers that are labeled as the crust, mantle, inner core, and outer core. The crust is the layer that you live on. It is the layer that is studied and understood the most. It is the thinnest of all the layers and contains oceanic and continental crusts. Oceanic crust (parts under the ocean) are about 3–5 miles in thickness, and continental crust (land) is about 25 miles thick. The crust of the Earth is made up of plates. These plates will sometimes build up pressure and stick together, the result is an earthquake. The mantle is the largest layer directly under the crust. It is about 1,800 miles thick, made up of very hot, dense rock. Because it gets so hot, it moves around like a melted liquid and causes the Earth’s plates to move. Scientists believe this happens because of convection currents. The outer core is the third layer of the Earth and surrounds the inner core. The outer core has a magnetic field. The magnetic field creates a protective barrier around the Earth that shields us from the Sun’s solar wind. The inner core is the innermost layer. It is a solid ball made of metal. The inner core is the hottest part of the Earth. It’s almost as hot as the Sun. Density is what determines how the layers of Earth are positioned. The inner core is denser than the other layers because it is actually a solid. It has more mass; therefore, it weighs more than the other layers. Its temperature also contributes to the amount of density it has. As the layers of Earth progress outward to the crust, they change in thickness, substances, and temperatures that cause them to be less dense. The density of something changes with temperature and pressure.

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Example of density.

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STEMscopedia: LAYERS OF EARTH Try Now Now that you have all this information on the Earth’s crust, mantle, and core, use this knowledge to create a brochure that is an educational pamphlet advertising an Earth Adventure Camp. Your goal is to show your understanding the Earth’s composition. You will play the role of the new Camp Director, advertising an Earth Adventure Camp to potential visitors. It should advertise what campers would expect to experience and should excite potential visitors about the new Earth Adventure Camp. Your brochure should have information on the following: Name of camp: Be creative, you are having a camp on the Earth’s layers. Include information on the following: The interior of the Earth. The lithospheric plates of the Earth. The plate boundaries. The major events caused by the movement of the plates.

Look Out What causes the Earth’s surface to change? What are the lithosphere and asthenosphere? The lithosphere is the Earth’s interior. It contains the crust and upper mantle and is broken into plates that are in constant motion. The motion of these plates are what create major geologic events like earthquakes, volcanic eruptions, and even mountain building. These major events, along with weathering and erosion, constantly change the surface of the Earth. There are different types of plates. The asthenosphere lies just below the lithosphere and can change shape without breaking. It can change shape because it has melt; this means that the interior reaches temperatures to melt the rocky composition.

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STEMscopedia: LAYERS OF EARTH What Do You Think? Do you think the Earth is one entire, solid unbroken planet? The Earth’s upper layer is broken up into plates, the lithospheric plates. How many different types of crust are there? What does the crusts’ density have to do with the surface of the Earth? There are two types of crust: continental and oceanic. The continental crust has less density and is closer to the surface. The oceanic crust is more dense and is lower. Why does the Earth have different layers? The Earth has four different layers. It is not really known how the Earth itself formed, but the way it formed its layers is by the heaviest elements sinking to the bottom, or in this case, to the middle. It is believed the Earth’s core is made of iron and nickel, with maybe a little sulfur. The core is the heaviest part of Earth. The mantle is the largest layer of Earth and is made of rock. The lightest layer is the crust. Has Earth changed its size since it was formed? Scientists do not think that the size of Earth has changed too much, but they do think the shape of it has. It seems to have flattened at the North Pole and South Pole, and it bulges at the equator. The flattening and bulging is caused by the spinning of the Earth. These forces have changed the shape over time. There has also been a shift in the location of the continents and oceans too.

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STEMscopedia: LAYERS OF EARTH Connecting With Your Child Convection currents are caused by the very hot material at the deepest part of the mantle rising, then cooling, sinking again and then heating, rising, and repeating the cycle over and over. The next time you heat something in a pan, you can watch the convection currents move in the liquid. The liquid in the bottom of the pan warms first, since it is closest to the heat source. This will cause a “current” of circulating liquid, as the warm liquid rises it causes the cooler liquid to sink to the bottom. This will continue until the liquid is all the same temperature. When the convection currents flow in the mantle, they also move the crust. It works very similar to the liquid in the pan. You can also make a Layers of the Earth Pizza. Think about different ingredients you can use for each layer. How thick should the layers be? Ingredients Pizza crust (crust) Pizza sauce Mozzarella cheese (mantle) Cheddar cheese (outer core) Tomato, pepperoni, or other topping (inner core)

Convection occurs when liquids are heated.

Directions Step 1: Spread pizza crust on pan (crust). Step 2: Spread pizza sauce. Step 3: Cover with a layer of mozzarella cheese (mantle). Step 4: Spread a thin, circular layer of cheddar cheese in the center of the pizza about 1½ inches from the edge (outer core). Step 5: Add a slice of tomato in the center of the cheddar cheese layer (inner core).

What toppings can you add to represent the Earth’s layers?

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6E5A Layers of Earth

Reading Science Name:

Date:

Group:

The Layers of Earth 1

We know that Earth’s surface has areas of water and land, but have you ever wondered what is deep inside this intriguing planet? Earth is full of surprises. If you were able to cut a section out of this ball of rock, you would see that it has three distinct layers. The crust, mantle, and core compose the layers of Earth.

The first of these three layers is called the crust. It is the layer that we live on. The crust, consisting of the continents and the ocean basins, is the thinnest of Earth’s layers. It ranges in thickness from 35–70 km thick under the continents to only 5–10 km thick under the oceans.

The crust and the mantle that lies below it are less dense than the core of Earth. Both the crust and the mantle are made mostly of silicates, minerals rich in the elements oxygen and silicon. The core contains the very dense iron and nickel elements. The explanation for Earth’s layers goes back to its formation into a solid planet. As Earth cooled, the less dense elements of the crust and mantle rose to the surface separating into layers around the innermost, dense core.

As one travels down through Earth’s layers, there are increases in both temperature and pressure, which are due to the mass of the overlying layers of rock. The mantle is the second layer of Earth. The upper portion of the mantle is mostly made of solid rock just like the crust above, but some of the upper mantle is semimolten and able to flow like a thick, gooey syrup. This allows the rigid, crustal plates resting on the upper mantle to float like giant pancakes. Even though people can’t feel it, the plates are slowly moving all of the time. The mantle stretches down into Earth for 2,900 km. Due to greater pressure down low, the lower mantle remains in a solid state of matter even though it is very hot.

In the center of Earth is the core consisting of two layers: the inner and outer core. The entire iron and nickel core is extremely hot, so it is not surprising to learn that the outer core is in a molten state. However, the inner core’s iron and nickel are solid. This seems impossible, but the inner core is kept solid by the intense pressure of all the layers above it. It spans a distance of 2,400 km and is surrounded by the outer core, which is about 7,000 km in diameter. The inner core plays an important role in the process that generates Earth’s magnetic field.

The three layers of Earth contribute to the uniqueness of this planet. The crust, mantle, and core are all distinctive: varying in composition, temperature, pressure, and state of matter. From a solid metal center, surrounded by a liquid core, to a sea of soft putty-like rock mantle, topped with a solid rock crust, there is no planet like Earth in the entire solar system.

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6E5A Layers of Earth

Reading Science 1.

What is the correct order of the layers of Earth starting deep in the center? A

Inner core, outer core, mantle, crust

Crust, mantle, outer core, inner core

Mantle, outer core, crust, inner core

Outer core, inner core, crust, mantle

Which statement best describes the crust? A

The crust is divided into sections and made of some of the densest rocks found in Earth.

The crust is the outermost layer of Earth composed of solid rock and divided into sections called plates.

The crust is made out of solid nickel and iron.

The crust is made of molten rock that flows like a thick, gooey syrup.

The core of Earth is made out of iron and nickel. The outer core’s temperature is so hot that it melts the metal. The inner core is solid metal. What causes these differences? A

The outer core is 2,300 km thick.

The inner core is kept solid by the intense pressure of all of the layers above it.

The inner core has a cooler temperature allowing the metal to remain solid.

The inner core is made of a different metal.

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6E5A Layers of Earth

Reading Science 4.

This layer of Earth is divided into two sections, both of which primarily contain silicate minerals. Part of one of the sections is able to flow like a thick fluid. What is this layer known as? A

Outer core

Mantle

Inner core

Crust

Complete the following analogy: EARTH’S INNER CORE : _____ :: EARTH’S OUTER CORE : MANTLE A

MAGNETIC

ATMOSPHERIC

SOLID

THERMAL

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6E5A Layers of Earth

Math Connections Name:

Date:

Group:

Earth contains distinct layers: the inner core, outer core, mantle, crust, and lithosphere. When constructing a model of Earth’s layers, each layer’s chemical composition, state of matter, and thickness should be considered. Use the steps on the following page to complete a replica of Earth’s layers in the grid below.

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6E5A Layers of Earth

Math Connections Follow the steps below to construct a model of Earth’s layers on the grid. • Plot the coordinates (5,−9) and (−5,−9). Connect them with a line. • Plot the coordinates (−8 , 1) and (8 ,1). Connect them with a line. • Plot the coordinates (−12¾, 14¾) and (12¾, 14¾). Connect them with a line. • Plot the coordinates (−13,15) and (13,15). Connect them with a line. • Plot the coordinates (−3,−15) and (3,−15). • Connect the coordinates (−3,−15) and (−13,15) with a line. • Connect the coordinates (3,−15) and (13,15) with a line. • Label each section of your model from top to bottom: Crust, Mantle, Outer Core, Inner Core. • Color each section a different color. The lithosphere is the layer of Earth comprising Earth’s Crust and Upper Mantle. • Draw the line y=14½ on the grid. • Between y=14½ and y=15, add slanted stripes to show the Lithosphere. Each square on the grid represents about 212 kilometers. Calculate the estimated thickness for each of Earth’s layers and write it in the corresponding empty space below. Layer

Chemical Composition

State of Matter

Lithosphere

Crust and upper Mantle

Solid and rigid

Crust

Lighter Elements: Al, Ca, Mg, K, and Na

Solid

Mantle

Silicates (Si, O), Magnesium, and iron

Varies from brittle, solid to molten state of magma

Outer core

Iron and nickel

Liquid

Inner core

Iron and nickel

Solid

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Average Thickness (km)

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6E5A Layers of Earth

Writing Science Name:

Date:

Group:

LOOK

THINK Think about the layers that make up Earth. WRITE Compare the similarities and differences between Earth’s crust, mantle, and core. Describe their differences in regards to temperature, density, and composition. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E5A Layers of Earth

Writing Science

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6th Grade Earth and Space Science

6E5B

Minerals and Rock Composition

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6E5B Minerals and Rock Composition

Student Handout

Name:

Date:

Observing Minerals and Vinegar Describe the color, shape, size, and texture of each object.

Chalk

Seashell

Limestone

How are the objects similar? How are they different?

Describe the reactions of the objects after you apply the vinegar.

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6E5B Minerals and Rock Contributions

Student Journal Name:

Date:

Group:

Part I: Identifying Mineral Content and Rock Properties Use the data tables to record your observations for Stations 1–5. Rock A Sample Data: Mineral Properties, Stations 1–5 Mineral Hardness Color Streak Magnetism Luster Fluorescence

Crystal Acid Cleavage Shape Test

1 2 3

Rock B Sample Data: Mineral Properties, Stations 1–5 Mineral Hardness Color Streak Magnetism Luster Fluorescence

Crystal Acid Cleavage Shape Test

1 2 3

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6E5B Minerals and Rock Contributions

Student Journal Part I: Identifying Mineral Content and Rock Properties, continued Rock C Sample Data: Mineral Properties, Stations 1–5 Mineral Hardness Color Streak Magnetism Luster Fluorescence

Crystal Acid Cleavage Shape Test

1 2 3

Rock D Sample Data: Mineral Properties, Stations 1–5 Mineral Hardness Color Streak Magnetism Luster Fluorescence

Crystal Acid Cleavage Shape Test

1 2 3

Rock E Sample Data: Mineral Properties, Stations 1–5 Mineral Hardness Color Streak Magnetism Luster Fluorescence

Crystal Acid Cleavage Shape Test

1 2 3 300

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6E5B Minerals and Rock Contributions

Student Journal Part I: Identifying Mineral Content and Rock Properties, continued Rock F Sample Data: Mineral Properties, Stations 1–5 Mineral Hardness Color Streak Magnetism Luster Fluorescence

Crystal Acid Cleavage Shape Test

1 2 3

Rock G Sample Data: Mineral Properties, Stations 1–5 Mineral Hardness Color Streak Magnetism Luster Fluorescence

Crystal Acid Cleavage Shape Test

1 2 3

Rock H Sample Data: Mineral Properties, Stations 1–5 Mineral Hardness Color Streak Magnetism Luster Fluorescence

Crystal Acid Cleavage Shape Test

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6E5B Minerals and Rock Contributions

Student Journal Part I: Identifying Mineral Content and Rock Properties, continued Use the data table below to record your observations for Station 6: Texture. Observations for Station 6: Texture Rock

Grains or Glassy

Interlocking or Cemented

Grain Size

Grain Distribution

Grain Shape

Grain Orientation

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6E5B Minerals and Rock Contributions

Student Journal Part II: Identification of the Minerals Within the Rocks Rock

Identity of Mineral

Property or Properties Used to Identify

Environment or Process of Mineral Formation

A A A B B B C C C D D D E E E F F F G G G

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6E5B Minerals and Rock Contributions

Student Journal Part II: Identification of the Minerals Within the Rocks, continued Rock

Identity of Mineral

Property or Properties Used to Identify

Environment or Process of Mineral Formation

H H H

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6E5B Minerals and Rock Contributions

Student Journal Reflections and Conclusions 1. Which information was the most helpful when identifying the rocks? Why?

2. Why is identifying the minerals within a rock important for identifying the rock?

3. Why is analyzing the texture of a rock important for identifying the rock?

4. How does knowing the environment or process of formation of the minerals in a rock help to categorize the rock?

5. Describe how rocks have a unique history that is related to the environment in which they formed.

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STEMscopedia: MINERALS AND ROCK

COMPOSITION 6E5B

Reflect

Rocks and Minerals What are rocks and minerals? What is the difference? What is Mohs scale of hardness for? Minerals are made up of one or more elements. Minerals form crystal structures because they are made up of many elements. Rocks are made up of one or more minerals. So there is not a difference between rocks and minerals because you need minerals to make up rocks. There are three basic types of rocks. They are called igneous, sedimentary, and metamorphic. The Earth is made of igneous rock. It can form as the magma from volcanic eruptions cools into its crystalline solids. Granite is a form of igneous rock, and when cleaned up and polished, it can be used for counter tops. Sedimentary rocks occur when they break off of larger existing rocks. This can be caused from weathering or just erosion of mountains. Metamorphic rocks are igneous and sedimentary rocks that transform because of heat and pressure. This is mostly caused by the shifting of the Earth. Mohs hardness scale is used measure the hardness of a mineral by how it resists being scratched. It is used to determine what an unknown mineral is.

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STEMscopedia: MINERALS AND ROCK

COMPOSITION

Try Now Growing Crystals Minerals are what rocks are made of, and rocks are what make up most of our Earth. We use rocks to build houses, buildings, cars, and toys. Did you know that even our bodies produce minerals. Certain rocks, like igneous rocks, have crystalline effects when they are formed. With this science project you do two things, you will see how crystals form in nature and make candy. Materials • Saucepan • Water • Sugar • Glass jar • String • Pencil Directions Step 1: Boil ½ cup of water in a saucepan. Step 2: Add 1 cup of sugar. Add one spoonful at a time until all the sugar is dissolved and turns into a clear syrup. Step 3: Let the syrup cool for about 10 minutes, then pour it into a glass jar. Step 4: Using a piece of string about 6 inches long, tie one end of the string around a pencil, put the pencil on top of the jar, so the string hangs in the syrup. Step 5: Now wait and watch what the syrup does. In a few days you should see crystals forming.

Look Out What Is Mining? Mining is the process of removing minerals and metals from Earth. There are many minerals/metals that can be mined, such as manganese, tantalum, copper, tin, nickel, bauxite (aluminum ore), iron ore, gold, silver, and diamonds.

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STEMscopedia: MINERALS AND ROCK

COMPOSITION

How Does Mining Affect the Environment? Mining is very destructive to the environment. Many trees and other plants are completely cleared from land causing thousands of animals to lose their homes. Large scale mining companies use huge bulldozers and excavators to extract the metals and minerals. In that process, they use harmful chemicals like cyanide and mercury. These chemicals usually end up being dumped into rivers, streams, bays, and oceans. From there, water and all its living organisms, like fish, are contaminated and ruined for human consumption.

An iron ore mining site.

How Does Mining Affect People? Mining also causes the people who are exposed to the toxic waste to become sick. They develop many different types of illnesses that include but are not limited to skin rashes, headaches, vomiting, diarrhea, etc. If the water is contaminated, people cannot use it for bathing, cooking, or washing clothes.

What Do You Think? Why Mine? There is a lot of money to be made in mining. Governments, mining companies, and their workers receive a lot of income and many benefits. Governments make money from the revenue. Mining companies make rich profits, and workers earn good incomes and benefits. What Are the Minerals and Metals Used For? Minerals and metals can be very valuable. Manganese is used to make low-cost stainless steel. Tantalum is used in cell phones, pagers, and laptops. Copper and tin are used to make pipes, cookware, and many other things. Gold, silver, and diamonds are used to make jewelry.

Examples of gold used in jewelry.

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STEMscopedia: MINERALS AND ROCK

COMPOSITION

Where Does Mining Occur? Mining occurs all around the world, including the United States. In South America, there are mines in many of its regions like Amazonia, Guyana, and Suriname. South Africa is also very well known for mining diamonds. Mining also occurs in Indonesia and other southeast Asian countries. What Can We Do as Global Citizens to Curb the Effects of Mining? • Make companies that exploit developing countries accountable for their actions. • Boycott products produced by companies that do not mine in environmentally responsible ways.

• Tell your family members, friends, teachers, and community members about the effects of mining. Make sure they know what to look for and only buy jewelry that is mined in a responsible way. • Protest against companies that do not pay for the damages they cause to rivers. • Spread awareness of this issue by sharing your knowledge. This is how change occurs.

Connecting With Your Child Your child has been learning about the contribution of minerals to rock composition. Help your child with the following. Problem How can you create a sedimentary rock? What takes place during the rock cycle?

Materials

Directions

Wax paper Magnifying glass Water Sugar Gravel Sand Spoon Paper cups

• Pour 1 spoonful of sand and 1 spoonful of gravel into a paper cup. • Fill another cup with 1 teaspoon of water. Stir in 5 spoonfuls of sugar until it is dissolved. • Pour the sugar water into the cup of sand and gravel until it is moistened. Pour off any excess water. • Let the “rock” dry. Carefully remove from the paper cup and put the rock on wax paper. • Let the rock sit and harden for at least 2 days. • Use a magnifying glass to observe your rock. • Draw an illustration of what you see. What kind of rock did you make?

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6E5B Minerals and Rock Composition

Reading Science Name:

Date:

Group:

Digging for Diamonds 1

The Crater of Diamonds is a 37.5 acre state park in Pike County, Arkansas. It is the only place where diamonds are found that is open to the public. The diamond-search area is the eroded surface of a prehistoric volcanic pipe. Over 95 million years ago, it brought diamonds and semiprecious stones to the surface. Today, visitors come to this site to dig through the plowed field. Visitors can find diamonds or other gem producing minerals, including amethyst, peridot, quartz, and garnet.

Now, suppose your parents tell you that this summer your family will be taking a road trip. You‘ll be visiting the Crater of Diamonds. Upon hearing the news, you are very excited. You’ve been sort of a “rock hound” for as long as you can remember. After all, you never could resist picking up a rock that sparkled in the light. Pretty-looking pebbles always seemed to catch your eye. This would be the perfect opportunity to explore gemology and add to your personal collection of gemstones!

Before the trip, you share some information about gemology and gemstones with your family. You let them know that gemstones are minerals that have been carefully cut and polished. This makes their surfaces smooth and shiny. People value gemstones because of their beauty, rarity, and durability. They’re often used to create jewelry or other decorative items. Traditionally, diamonds, rubies, emeralds, and sapphires have been considered as precious stones due to their rarity, hardness, and overall clarity. All other gemstones are considered semiprecious because they’re more common and are softer. Many semiprecious stones are very popular. They can be used to create beautiful jewelry. You tell your family to be on the lookout for the more common semiprecious stones found at the Crater of Diamonds.

As the big trip gets closer, everyone in your family is getting excited about visiting the Crater of Diamonds. You’ve decided that the time has come to share the most important information with your family: how to spot a diamond. After all, it’s important to know whether they’ve found a diamond or just a plain old rock. You share that four physical properties are used to identify a mineral. These are hardness, color, luster, and streak.

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6E5B Minerals and Rock Composition

Reading Science Continued 5

Hardness describes the strength of the forces holding atoms together in a solid mineral. The Mohs scale is used to describe how easily a mineral can be scratched. It has a range from 1–10. Diamonds are rated a 10 on the Mohs scale. They are the hardest minerals in the world. The color of a mineral is often easy to identify. Many minerals are found in a wide range of colors. Diamonds are no exception. They can be yellow, brown, blue, green, orange, purple, black, pink, red, or colorless. Colored diamonds have impurities that cause them to be different colors. Colorless, transparent diamonds, however, are nearly pure. Luster refers to the way a mineral looks as it reflects light.

A mineral’s luster could be metallic, dull, pearly, or adamantine. Diamonds have adamantine luster, which is seen in their brilliant sparkle. The term streak refers to the color of the powder left by a mineral. The streak of a mineral is often found by scraping a mineral along the nonglazed side of a porcelain tile. The color of the mark left on the tile helps to identify the mineral. The streak of a diamond is white.

You’ve explained how a mineral’s physical properties can be tested to identify it. You also tell them that some of these tests work better in a laboratory. Now that your family knows how physical properties are used to identify minerals, they’re even more excited to dig up some hidden gems. As summer gets closer, you and your family are getting more and more excited about your trip to the Crater of Diamonds. Who knows what treasures you’ll find!

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6E5B Minerals and Rock Composition

Reading Science 1.

Paragraph 5 of this passage mainly tells about – A

the physical properties of minerals.

how to spot a diamond.

determining how rare a diamond is.

how to test a diamond for value.

Complete the following analogy: SCRATCH TEST: HARDNESS ::

METALLIC : LUSTER

PORCELAIN TILE : STREAK

COST : DIAMOND PURITY

COLORED DIAMOND : CLEAR DIAMOND

The reader can tell from this passage that – A

the narrator will definitely find a diamond at the Crater of Diamonds State Park.

diamonds are rare, valuable gems.

garnet is as valuable as a diamond.

semiprecious stones are ugly.

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6E5B Minerals and Rock Composition

Reading Science

Adamantine

Colorless

White

The table above displays the physical properties of diamond, but the property names have been left out of the first row. Which property name belongs in column 1? A

Color

Streak

Luster

Hardness

Which property of a mineral is expressed using Mohs scale? A

Luster

Hardness

Monetary value

Streak

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6E5B Minerals and Rock Composition

Math Connections Name:

Date:

Group:

Rocks are classified based on their formation processes and their mineral compositions. Most rocks contain some minerals. Nine families of rocks are classified by the minerals found in them. The table below shows some of those rock families, the minerals found in them, and the mineral’s chemical makeup. Rock Families and Minerals Use the table to answer the questions below: Rock Family

Minerals

Elements

Gold Silver Copper Carbon Sulfur Cinnabar

Sulfides

Galena Pyrite Fluorite

Halides Halite Corundum Oxides

Cuprite Hematite

Chemical Makeup 100% Gold 100% Silver 100% Copper 100% Carbon 100% Sulfur 86% Mercury 14% Sulfur 86% Lead 14% Sulfur 47% Iron 53 % Sulfur 51% Calcium 49% Fluorine 40% Sodium 60% Chlorine 53% Aluminum 47% Oxygen 90% Copper 10% Oxygen 70% Iron 30% Oxygen

hat element do the minerals found in W sulfide rocks have in common?

ketch three pie charts to represent S the chemical makeup of the minerals that comprise the sulfide family. Cinnabar Mercury Sulfur Galena Lead Sulfur Pyrite Iron Sulfur

What do rocks in the oxide group have in common?

If a rock in the oxide family was found to contain 260 grams of cuprite in it, what percent of the cuprite would be copper?

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percent

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6E5B Minerals and Rock Composition

Math Connections Rock Families and Minerals Rock Family Minerals Chemical Makeup 40% Calcium Calcite 12% Carbon 48% Oxygen 22% Calcium 13% Magnesium Dolomite Carbonates 13% Carbon 52% Oxygen 57% Copper 1% Hydrogen Malachite 6% Carbon 36% Oxygen 29% Calcium Anhydrite 24% Sulfur 47% Oxygen Sulfates 23% Calcium 2% Hydrogen Gypsum 19% Sulfur 56% Oxygen 40% Calcium 18% Phosphorus Phosphates Apatite 38% Oxygen 4% Fluorine 5% Beryllium 10% Aluminum Beryl 31% Silicon 53% Oxygen 10% Potassium 20.5% Aluminum 21% Silicon Muscovite 0.5% Hydrogen Silicates 47% Oxygen (SiO2) 1% Fluorine 14% Potassium 10% Aluminum Orthoclase 30% Silicon 46% Oxygen 47% Silicon Quartz 53% Oxygen 11% Hydrogen Organics Amber 80% Carbon 9% Oxygen 316

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hich two elements do all of the W minerals in the carbonate family have in their chemical makeup?

reate two pie charts to represent C the chemical makeup of the minerals found in rocks in the sulfate family.

Anhydrite Calcium Sulfur Oxygen

Gypsum Calcium Sulfur Oxygen

I f a rock in the silicate family was found to contain 150 grams of quartz in it, what percent of the quartz would be silicon? percent

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6E5B Minerals and Rock Composition

Writing Science Name:

Date:

Group:

LOOK

THINK Think about various types of rocks and what they are composed of. WRITE Describe the composition of sedimentary, igneous, and metamorphic rocks, and explain how minerals play a role in the makeup of each type of rock. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E5B Minerals and Rock Composition

Writing Science

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6th Grade Earth and Space Science

6E 5C

Classifying Rocks

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6E5C Classifying Rocks

Student Journal Name:

Date:

Group:

Background 1. What are the three basic categories of rocks?

2. What characteristic is used to determine the three categories?

3. List each category of rock and describe how it forms. A. B. C. 4. What is the rock cycle?

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6E5C Classifying Rocks

Student Journal Part I: The Rock Cycle Sedimentary Rocks 1. Draw your sedimentary rock model in this space. Answer the following three questions on the lines below about your model rock and the real sedimentary rock sample. What processes were involved in the formation of your model? How is your model similar to the real sedimentary sample? How is your model different from the real sedimentary sample?

Metamorphic Rocks 2. Draw your metamorphic rock model in this space. Answer the following three questions on the lines below about your model rock and the real metamorphic rock sample. What processes were involved in the formation of your model? How is your model similar to the real metamorphic sample? How is your model different from the real metamorphic sample?

Igneous Rocks 3. Draw your igneous rock model in this space. Answer the following three questions on the lines below about your model rock and the real igneous rock sample. What processes were involved in the formation of your model? How is your model similar to the real igneous sample? How is your model different from the real igneous sample?

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6E5C Classifying Rocks

Student Journal Part I: The Rock Cycle, continued The Rock Cycle 4. You have taken a rock through one pathway of the rock cycle! Use this experience to diagram the pathway you modeled through the rock cycle. Use the terms and process words in the word bank to complete the diagram. Terms

Processes (Arrows)

Igneous rock Metamorphic rock Sedimentary rock Sediments Magma

Weathering, erosion, and deposition Extreme heat and pressure Cooling and solidifying Melting Compaction and cementation

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6E5C Classifying Rocks

Student Journal Part II: Igneous Rock Formation 1.

What does the liquid or melted crayon represent in this model?

Draw a diagram to show what occurred as the liquid was poured into the three different glasses in the boxes below. Write a description of the appearance in the space beside the diagram and include how quickly or slowly the wax cooled and hardened.

a. Over Ice

b. In Cold Water

c. In Warm Water

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6E5C Classifying Rocks

Student Journal Part II: Igneous Rock Formation, Continued 3.

What controls the size of the crystals formed in igneous rocks?

Use the three following phrases to identify which type of formation is represented by each of the three models. • •

Cooling such as when lava flows over land. Very slow cooling such as what occurs when magma is trapped beneath Earth’s surface.

•

Rapid cooling such as when lava flows into water.

Glass with ice: Glass with cold water: Glass with warm water: 5.

Use the descriptions of each model type in question 4 to identify which method of cooling formed the three igneous rock samples of obsidian, granite, and basalt. Obsidian: Granite: Basalt:

In what way is this a good model of how igneous rock forms?

In what way is this not a good model of how igneous rock forms?

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6E5C Classifying Rocks

Student Journal Reflections and Conclusions 1.

What is the effect of temperature in the formation of igneous rocks?

What properties did you identify when observing the sedimentary rock? How do these properties relate to the formation of sedimentary rocks?

What properties did you identify when observing the metamorphic rock? How do these properties relate to the formation of metamorphic rocks?

How is the formation of metamorphic rocks different from that of igneous rocks even though both can take place underground?

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6E5C Classifying Rocks

Student Journal Reflections and Conclusions, continued 5.

Make a T chart to compare the formation processes of igneous, sedimentary, and metamorphic rocks.

6. Label the action (process) that occurs along the arrows to complete the diagram of the rock cycle.

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STEMscopedia: CLASSIFYING ROCKS

6E5C

Reflect Have you ever looked out your window and wondered what your backyard may have looked like a million years ago? What kinds of animals and plants lived there? Was there a volcano, a river, or an ocean? Did massive glaciers pass through and carve up the land? Next time you pick up a rock, you might just be holding the key to unlocking these mysteries! Scientists called geologists study rocks to learn about Earth’s history. What kinds of information do you think a geologist could learn from the rocks around you? There are three main types of rocks. Geologists classify rocks into three main categories: sedimentary, igneous, and metamorphic. Rocks are separated into these three types based on how they were made. A rock’s physical characteristics reflect the processes under which it formed. So does a rock’s mineral composition.

In the rock cycle, any type of rock can become any other type of rock.

When rocks undergo additional processes, they can change from one type of rock to another. Depending on the processes the rock goes through, any type of rock can become any of the other types. It could even become a new rock of the same type. For example, a sedimentary rock could become a metamorphic rock, an igneous rock, or a new type of sedimentary rock, depending on what happens to it. The processes by which rocks change into new rocks make up the rock cycle.

Mineral: a naturally occurring, inorganic solid with a fairly constant chemical composition and fairly constant crystal structure

Igneous rocks have characteristics unique to how they form. Igneous rocks are formed when lava or magma cools and solidifies. This solidification is known as crystallization. Lava and magma are both molten rock. Rocks that melt under Earth’s surface are known as magma. When magma erupts out of a volcano, or seeps through cracks in Earth’s crust, it becomes known as lava. Igneous rocks have interlocking mineral crystals. These crystals vary in size depending upon how rapidly they cooled. When magma cools under Earth’s surface, it solidifies very slowly. This gives mineral crystals a long time to grow. This allows the crystals to become quite large. Igneous rocks that cool slowly under Earth’s surface are known as intrusive igneous rocks. (Think of “internal.” Intrusive igneous rocks form in Earth’s interior.)

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STEMscopedia: CLASSIFYING ROCKS It is much cooler on Earth’s surface than it is below. When lava cools on Earth’s surface, it solidifies very quickly. This does not give mineral crystals very much time to grow, so they will be quite small. Sometimes, they will cool so quickly that no crystals will form at all. In that case, the rock will have the characteristics of glass. A volcano may shoot blobs of lava into the air. These blobs can cool so quickly that they solidify before they even hit the ground. Igneous rocks that cool quickly on or above Earth’s surface are known as extrusive igneous rocks. (Think of “external.” Extrusive igneous rocks form on Earth’s exterior.) Sometimes, gases are dissolved in magma. When the magma rises to Earth’s surface and becomes lava, the pressure of being underground is released. This allows the gases to escape, forming bubbles. You can observe this yourself by opening a brand new bottle of soda. When you first open the cap, you hear the pressure being released. You see all of the bubbles rising to the surface. Bubbles leave holes as the lava cools and becomes an extrusive igneous rock. Sometimes, the rock is so full of holes, it will even float in water! Take a look at these two photographs. Both show igneous rocks. The igneous rock pictured on the left has very large interlocking crystals. It is an intrusive (form in Earth’s interior) igneous rock. The igneous rock pictured on the right has very small interlocking crystals. It is an extrusive (form on Earth’s exterior) igneous rock.

What Do You Think? As part of the rock cycle, old igneous rocks can form new igneous rocks. How do you think this can happen? (Recall that igneous rocks form when rocks that have melted cool and solidify.)

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STEMscopedia: CLASSIFYING ROCKS Sedimentary rocks have characteristics unique to how they form. Forces on Earth’s surface can break down rocks. This process is called weathering. Rocks can be broken down through physical weathering or chemical weathering. Physical weathering breaks down rocks into smaller pieces through physical processes. For example, other materials can scratch or scrape them. Chemical weathering breaks down rocks through chemical processes. For example, they can be dissolved by acid rain. Once rocks are broken down, the smaller pieces are called sediments. Sediments can be carried from place to place. This process is called erosion. Erosion carries sediments through wind, water, gravity, or other means. For example, sediments can travel downstream in a river. They can also roll downhill in a landslide. Eventually, sediments stop moving and settle into layers. This process is called deposition. Layers of sediment can be crushed together as more sediment is deposited on top. This crushing is called compaction. Sometimes, water will fill in the tight spaces between the grains of sediment. Eventually, the water evaporates. When this happens, any minerals that were dissolved in the water are left behind. Small mineral crystals grow while the water evaporates. These crystals “glue” the sediment grains together in a process called cementation. Once the sediment grains are bound together, they become a sedimentary rock.

These hills are made of layers of sedimentary rock called sandstone. These layers of sandy sediment were deposited one on top of another.

Sometimes minerals will grow in the spaces left behind by the bodies of dead animals or plants. This creates fossils in some sedimentary rocks. Some fossils form when minerals fill footprints and other traces of living things.

Some sedimentary rocks contain fossils like this fish. Minerals replaced the remains of the fish, leaving its shape behind.

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STEMscopedia: CLASSIFYING ROCKS After rocks are dissolved through chemical weathering, crystals can grow as the water evaporates. This is a different kind of deposition. This results in sedimentary rocks called evaporites. Salt is one of the main minerals that forms evaporites. When many salt crystals grow together, a sedimentary rock called rock salt forms. Many evaporite sedimentary rocks are made of only one mineral. Sedimentary rocks that are created through deposition and cementation of sediment are typically made of more than one mineral. Cementation occurs when minerals grow in between other grains of sediment and glue them together.

Rock salt forms when many individual salt crystals grow together.

Metamorphic rocks have characteristics unique to how they form. Rocks are often buried in Earth’s crust. Sometimes sediment is deposited on top of them over time. Sometimes they are buried through the movement of tectonic plates. As they become buried deeper and deeper, the weight of the crust above puts pressure on the rocks. In addition, as the rocks get closer to the mantle, their temperatures increase.

Tectonic plates: the solid pieces of Earth’s crust that float and move on top of the asthenosphere

Mantle: the solid layer of Earth between the crust A rock is defined by its texture, as well as its composition—the and the core minerals of which it is made. Therefore, if a process changes a rock’s texture, its composition, or both, the rock will become a new and different rock. When rocks are buried deep in Earth’s crust, heat and pressure can cause the buried rocks to be altered to form new rocks. These are called metamorphic rocks. Metamorphic rocks are often characterized by wavy layers of mineral crystals or by the presence of unusual minerals.

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STEMscopedia: CLASSIFYING ROCKS Pressure can change an existing rock into a new metamorphic rock by changing the rock’s texture. Sometimes the sediment grains of a sedimentary rock or the crystals of an igneous or other metamorphic rock will be squeezed tightly together. This can change the rocks into new, denser metamorphic rocks. Many sedimentary rocks already contain parallel layers. These parallel layers can be squeezed by pressure and become the wavy layers of a metamorphic rock.

See the wavy layers in this metamorphic rock? The minerals were squeezed together into these wavy layers by pressure. This metamorphic rock is called gneiss.

Pressure can also change an existing rock into a new metamorphic rock by changing the rock’s mineral composition. A mineral is defined by the elements of which it is made and by its crystal structure. The crystal structure is the internal arrangement of the atoms that make up the crystal. Sometimes the pressure is great enough that it will change the internal arrangement of atoms by crushing the atoms together. Because this changes the crystal structure, it changes the minerals. Changing the minerals into different minerals changes the mineral composition of the rock. Changing the mineral composition of a rock changes it into a new metamorphic rock.

Heat can also change an existing rock into a new metamorphic rock by changing the rock’s mineral composition. Heat can cause chemical reactions that change minerals into new minerals. Heat can also cause water or other chemicals to evaporate out of certain minerals. These chemical reactions change the mineral composition of the existing rock into a new metamorphic rock with a different mineral composition.

Look Out When heat changes an existing rock into a new metamorphic rock, the rock may become soft. This makes it easier for pressure to change the rock’s texture. However, the rock will still be in solid form. Suppose the heat is great enough to actually melt the rock into liquid form. When the rock solidifies again, it will become an igneous rock, not a metamorphic rock. Heat changing rocks is like candle wax. A little bit of heat will make the wax soft enough for you to mold it into a new shape.

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How is a melting candle similar to a rock in the rock cycle?

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STEMscopedia: CLASSIFYING ROCKS However, the wax will remain a solid. This represents the way heat softens rock so that pressure can change its texture, creating a metamorphic rock. A lot of heat will cause the wax to melt into a liquid. Eventually, the wax will cool again and become solid. This would represent the way rock melts and solidifies, creating an igneous rock. Career Corner: Petrologist Petrology is a branch of geology that specifically focuses on the textures, composition, and formation of rocks. Geologists who primarily focus on petrology are called petrologists. While some petrologists study all types of rocks, many petrologists will focus specifically on igneous, metamorphic, or sedimentary rocks. Petrologists sometimes do chemical testing on rocks to determine their mineral compositions. They can also polish rock samples until they are so thin that light can pass through them! This allows petrologists to examine the rocks using special light microscopes called petrographic microscopes. Petrologists can learn detailed information about the compositions and textures of rocks by examining these thin sections. Petrologists are experts on the rock cycle. As rocks move through the rock cycle, their mineral compositions and physical structures change to reflect the processes under which they are formed. By studying the textures and compositions of rocks, petrologists can learn a lot about how the rocks formed. The physical structures and chemical properties of the solid Earth provide evidence of Earth’s evolution over time. Investigation of Earth’s layers, tectonic activity, and the rock cycle reveals Earth’s history. Petrologists play a major role in revealing Earth’s history by studying the rock cycle. What Do You Know? Over time, through the various processes of the rock cycle, Earth’s rocks change from one type into another. Read the processes in the box below. Write each process in the correct place of the rock cycle diagram on the next page. Rock Cycle Processes • Erosion

• Cementation

• Pressure

• Crystallization

• Meltings

• Weathering

• Heat

• Deposition • Compaction

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STEMscopedia: CLASSIFYING ROCKS

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STEMscopedia: CLASSIFYING ROCKS Connecting With Your Child Exploring the Rock Cycle at Home To help students learn more about the rock cycle, try exploring rocks together. Rocks are classified into sedimentary, igneous, and metamorphic rocks. Each class of rock is defined by the processes of its formation. The texture and mineral composition define different types of rocks; they are also determined by the processes by which the rocks formed. Over long periods of time, Earth’s rocks change from one type into another through various processes as described in the rock cycle. The processes that form sedimentary rock include weathering, erosion, deposition, compaction, and cementation. The processes that form igneous rock include melting and crystallization. The processes that form metamorphic rock include changing heat and pressure. • Sedimentary rocks are formed when particles of other rocks are deposited in layers and undergo compaction (crushing together) and cementation (binding of the sediments). Some sedimentary rocks contain fossils. • Igneous rocks are formed when lava or magma cools and solidifies. They are characterized by interlocking mineral crystals that vary in size depending upon how rapidly they cooled. • Metamorphic rocks are formed deep underground where heat and pressure cause existing rocks to be altered. Metamorphic rocks are often characterized by wavy layers of mineral crystals or by the presence of unusual minerals. Take your child on a walk outside. Pick up any rocks you find along the way. Take a close look at the rocks. Discuss any observations your child makes about the rocks, paying particular attention to the textures, layers, grain sizes, or other features, such as fossil evidence. Although it may not be possible to identify the rocks, have your child explain whether the rock is igneous, sedimentary, or metamorphic. Your child should also explain why the rock fits into that category. If you live in an urban area, your child might mistake concrete or asphalt for different types of rocks. These products typically include crushed rocks and sediments such as sand, concrete, and asphalt; however, these materials do not form naturally as part of the rock cycle. Humans make them by binding crushed materials with various pastes (such as cement). In this respect, concrete and asphalt are similar to sedimentary rocks formed by cementation, but they are not actually rocks. Here are some questions to discuss with students: • What features do you see in this rock? • Do you see grains of sediment or crystals? • Do you see any layers? Are they parallel or wavy? • What size crystals do you see in this rock? • What kind of rock do you think this is (sedimentary/igneous/metamorphic)? Why do you think so?

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6E5C Classifying Rocks

Reading Science Name:

Date:

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Classifying Rocks 1

Have you ever picked up an interesting rock? Maybe you wondered where it came from or how it was made. If you look, you will discover that rocks are all around us. This is not surprising since we live on the crust of Earth, which is made up entirely of rock. Would you be shocked to learn that some of these rocks have been around for billions of years? Most aren’t quite so old. New rocks are slowly formed all the time. Old rocks are slowly worn away by erosion. But no matter how old the rock, they were all formed in some way.

There are three categories of rocks based on the way they were formed. Volcanic action results in the formation of igneous rock. Layer upon layer of deposited material results in sedimentary rock. Extreme heat or pressure will cause some rocks to change into metamorphic rock. These different formation processes give each type a characteristic appearance. This lets us classify rocks into one of the three categories.

Deep under Earth’s crust, the temperature is hot enough to melt rocks. This molten rock is called magma. Rock is formed within the crust as the magma slowly cools and hardens. Sometimes volcanic action brings magma through the crust. When this happens, the molten rock is called lava rather than magma. As the lava flows, it also cools and hardens. The types of rocks that are formed by magma or lava are known as igneous rocks. Granite is an example of an igneous rock.

Sedimentary rock is the second category. These rocks cover about three-quarters of Earth’s land surface. Sedimentary rocks are made of pieces of other rocks and shells. Rain, wind, freezing, and plant roots can all cause erosion of rocks. As rocks are exposed to these elements, they are slowly worn away. These pieces of rock, now called sediment, are eventually carried by rivers to the oceans and lakes. As the water slows down, the sediments settle to the bottom, layer by layer. Over millions of years, the weight from the upper layers of sand and mud turn these layers of sediment into rock. Some sedimentary rocks appear to be banded or layered because of this. Also, many fossils can be found within the layers of sedimentary rocks.

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6E5C Classifying Rocks

Reading Science Continued 5

Metamorphic rocks are the third and final category. Metamorphic rocks are the least common rock found on Earth. These rocks were once an igneous, sedimentary, or even metamorphic rock. They were changed by extreme pressure and heat while deep inside Earth. Enough heat and pressure will change a rock’s appearance, structure, and composition. This results in the formation of a different rock. Granite, an igneous rock, will become gneiss when it is placed under heat and pressure. Limestone, a sedimentary rock, will become marble when it is placed under heat and pressure. Think of metamorphic rocks as rocks that have changed.

Take a good look the next time you pick up a rock. Think about how it could have been formed. Was it formed by molten magma cooling and hardening or by layers of sediments pressing down on each other over time? Was it changed by heat and pressure into an entirely different rock? On Earth, there are only these three types of rocks—igneous, sedimentary, and metamorphic.

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6E5C Classifying Rocks

Reading Science 1.

As a volcano erupts, it produces lava. As this lava flows, it cools down and hardens, forming a rock. How could this rock be classified? A

As molten magma

As a sedimentary rock

As a metamorphic rock

As an igneous rock

Sometimes fossils can be found in sedimentary rocks. Which statement best explains why? A

Heat and pressure from deep within Earth cause fossils to form.

The remains of dead plants and animals settle to the bottom of an ocean or lake and are covered by mud. Pressure eventually forms these layers into rock.

Lava may flow over an animal or plant, and as it cools and hardens, a fossilized rock is formed.

Larger rocks are slowly eroded by the elements on Earth.

A metamorphic rock can also be thought of as a rock that changes. What causes the rock to change? A

Layers of sediment building up over time and pressing down form rock.

Rain, wind, freezing, thawing, and plant roots growing cause the rock to erode leaving behind sediments.

Extreme heat and pressure from deep within Earth cause changes to the rock’s appearance, structure, and composition.

The rock slowly changes over time into a new rock.

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6E5C Classifying Rocks

Reading Science 4.

Based on the context in paragraph 4, fossil refers to – A

how igneous rocks were formed over time.

the remains of dead plants and animals settle to the bottom of an ocean or lake and are covered by mud.

a trace or print or the remains of a plant or animal of a past age preserved in earth or rock.

layers of sediment building up over time and pressing down forming rock.

What is similar about igneous rock and metamorphic rock formation? A

The formation of igneous rock and metamorphic rock requires extreme heat.

The formation of igneous rock and metamorphic rock occurs deep underground.

The formation of igneous rock and metamorphic rock results in rocks that have a similar appearance.

The formation of igneous rock and metamorphic rock requires layering.

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6E5C Classifying Rocks

Math Connections Name:

Date:

Group:

Igneous, metamorphic, and sedimentary rocks have unique characteristics that can be used for identification and/or classification. Igneous rocks are formed when lava or magma cools and solidifies. They are characterized by interlocking mineral crystals that vary in size depending upon how rapidly they cooled. Solve the equations below and match them to their answers to figure out the texture and composition of each type of igneous rock. (The first rock is answered for you.) Name

Texture

Composition

Granite

2x = 6

Diorite

12 + x = 15

5x = 150

Gabbro

90x = 270

x + 65 = 85

Peridotite

45x = 135

17x = 68

Porphyritic rhyolite

16 + x = 39

36 + x = 61

Porphyritic andesite

2x = 46

78 + x = 108

Porphyritic basalt

x + 49 = 72

5x = 100

Rhyolite

3x = 99

19 + x = 44

Andesite

x + 14 = 47

x + 96 = 126

Basalt

5x = 165

6x = 120

Obsidian

3x = 48

F, I or M

Pumice

16 + x = 58

F or I

Scoria

3x = 126

Volcanic tuff & breccia

Coarse-grained

31 + x = 56

Felsic

x + 56 = 76

54 + x = 89

F, I or M

Texture

Composition

Coarse-grained

Felsic:>5% quartz &<15% dark minerals

Porphyritic – different sized crystals

Intermediate:<5% quartz & 15 –10% dark minerals

Fine-grained

Mafic: no quartz; no feldspar &>40% dark minerals

Glassy – smooth & shiny

Ultramafic: 100% dark minerals

Vesicular – many cavities or wholes

Pyroclastic – volcanic material

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6E5C Classifying Rocks

Writing Science Name:

Date:

Group:

LOOK

THINK Think about the ways scientists classify rocks. WRITE Explain the processes by which rocks are formed. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E5C Classifying Rocks

Writing Science

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6th Grade Earth and Space Science

6E5DE

Weather, Erosion, and Deposition

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6E5DE Weathering, Erosion, and Deposition

Student Journal Name:

Date:

Group:

Explore 1: Weathering and Erosion by Flowing Water Part I 1. Draw a picture of your results in the space below. Label your drawing.

How did changing the shape of your river alter your results? Draw a picture in the space below and label it.

Part II After using the index card to create waves, what changes did you see? Sketch a picture of your results in the space below.

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6E5DE Weathering, Erosion, and Deposition

Student Journal Name:

Date:

Group:

Explore 2: Weathering and Erosion by Ice Day 1 Part I Record observations about your glacier in the table below. Include sketches and labels.

Glacier (starting)

Glacier (3 min)

Glacier (6 min)

Glacier (9 min)

Glacier (12 min)

Part II Draw a diagram of the model. Write a prediction of what will occur in the model. Sketch:

Prediction:

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6E5DE Weathering, Erosion, and Deposition

Student Journal Day 2 Observe your model from yesterday. What happened?

Answer the following questions. 1.

What change in the shoreline did you see?

What process does this model represent?

Look at the shoreline images provided. What conclusion can you make about glaciers using the images and your observations? Use the following sentence stem to help you.

Glaciers change the shape of Earth’s surface by

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6E5DE Weathering, Erosion, and Deposition

Student Journal Name:

Date:

Group:

Explore 3: Deposition and Slope Scientific Investigation Gravity moves rocks and sediments downhill. The steeper the slope of the ground that the water is running over, the faster the water will travel. As water travels, it carries sediment downstream. When the water slows down, the sediment is deposited. Weathering, erosion, and deposition lead to changes in Earth’s surface.

Procedure Step 1: Question

Step 2: Relevance

Step 3: Variables, if applicable Independent variable (What are you changing/testing?): Dependent variable (What are you measuring/observing?): Constant variables (What will stay the same among your trials?): Step 4: Hypothesis Is a hypothesis needed? If so, what is it? How will the responding variable change when the manipulated variable changes? © Accelerate Learning Inc. - All Rights Reserved

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6E5DE Weathering, Erosion, and Deposition

Student Journal Deposition and Slope Scientific Investigation, continued Step 5: Materials

Step 6: Safety considerations

Step 7: Procedure 1.

Set up stream table as in previous activities.

Leave an area at the bottom of the paint tray for the ocean.

Trial 1 3. Draw a river down the sand. 4.

Pour three 300-mL beakers of water onto the sand at the top of the riverbed. Remove water from the ocean as needed, trying not to disturb the sand that is forming at the end of the river. This sand is known as a delta. A delta forms at the end of a river where the water slows down to enter a larger body of water, such as an ocean.

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6E5DE Weathering, Erosion, and Deposition

Student Journal Deposition and Slope Scientific Investigation, continued 5.

Make a drawing of the river and the delta it forms.

Measure the width and depth of the delta and record it in the data table on the following page.

Replace the delta sand back into the landform. Smooth out the sand again.

Trial 2 8. Draw a river down the sand like the river in Trial 1. 9.

Place a book under the top (land) so that it is higher with a greater incline.

10. Pour three 300-mL beakers of water onto the sand at the top of the riverbed. Remove water from the ocean as needed trying not to disturb the sand that is forming the delta. 11. Make a drawing of the river and the delta it forms.

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6E5DE Weathering, Erosion, and Deposition

Student Journal Deposition and Slope Scientific Investigation, continued 12. Measure the width and depth of the delta and record it in the data table below. 13. Replace the delta sand back into the landform. Smooth out the sand again.

Trial 3 14. Draw a river down the sand like the river in Trial 1. 15. Place a second book under the top (land) so that it is higher with a greater incline. 16. Pour three 300-mL beakers of water onto the sand at the top of the riverbed. Remove water from the ocean as needed trying not to disturb the sand that is forming the delta. 17. Make a drawing of the river and the delta it forms.

18. Measure the width and depth of the delta and record it in the data table below. Step 8: Data Collection Use the table to record your data. The Effect of Slope on Deposition Slope Type

Width of Delta

Depth of Sand

Slight Medium Steep 354

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6E5DE Weathering, Erosion, and Deposition

Student Journal Deposition and Slope Scientific Investigation, continued Step 9: Data Analysis Create a graph based upon the data if needed. Make a general statement about the results shown in graph.

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6E5DE Weathering, Erosion, and Deposition

Student Journal Deposition and Slope Scientific Investigation, continued Step 10: Conclusion and Scientific Explanation Write a scientific explanation on how the slope of the landform affects the rate of deposition in a delta.

Reflections In the space below, record questions you could share with your group that would help them identify agents of weathering and erosion and to identify landforms created by deposition.

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6E5DE Weathering, Erosion, and Deposition

Reading Science Name:

Date:

Group:

Mapping Erosion Control 1.

Have you ever noticed that plastic fencing around a building site and wondered why it’s there? The answer is erosion control. Before an architect begins to design a building, he or she must conduct a site survey. One of thesteps in a site survey is to look at the elevations of thebuilding site and surrounding areas.

Elevations are found on topographic maps. Topographic maps show large and small hills, streams, rivers, valleys, and man-made features. This information helps the architect decide where to build the structure on the site. It would not be a good idea to place a structure near a river that could erode away all of the sediment from under the building. The architect also has to consider where people will park their cars. If the land is too steep, the cars could roll down the hill! Much of the information needed to properly design the building site is shown on a topographic map.

After the architect decides where to place the building on the site, he or she must consider erosion. Before building can begin, the trees will be cut down. All the plants will be scraped away by bulldozers. Water is a major cause of erosion, but plants hold soil in place. After the vegetation is gone from the site, rain will cause the soil to move downhill. Using the topographic map, the architect will be able to predict which direction the soil will move. He or she will then tell the builder where to place fences to help stop erosion. This is why the information from the topographic map is valuable.

The plastic fences around building sites are called silt fences. Silt is a very small sediment. These fences are placed at the bottom of the hill or along a roadway. The silt fences keep the eroding soil from going into a waterway, such as a stream or the drainage system of a city or town. If silt gets into a stream, sediment deposition can dam up the stream and cause flooding upstream and loss of water downstream.

Look at the two satellite photographs of the Pareechu River in Tibet. You will see what happens when erosion happens on a large scale. The top picture shows the Pareechu River after it has been blocked. Can you see the landslide in the lower right corner? This landslide was caused when heavy rains loosened the soil and rock at the top of a hill. Gravity caused them to slide down into the river. The large blue area is a landslide lake that was formed after the landslide blocked the river. You can also see how wide the river has become.

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6E5DE Weathering, Erosion, and Deposition

Reading Science 6.

The bottom photograph was taken almost a year later. The water has started to drain out of the lake. The lake has gotten smaller, and the river behind it is not as wide. It is obvious that the land around the lake has hills and valleys. Satellite photographs like these give a clear picture of different erosional features such as landslides and deltas. These pictures allow scientists to study the features for changes over time.

Scientists can use topographic maps together with satellite views to gain vast amounts of information. Topographic maps don’t change much unless there is a catastrophic natural disaster, such as when a volcano explodes. During a catastrophic event, satellite pictures can change daily. A satellite view can show the visual difference as seasons change. Satellite photographs show how much vegetation is present from one season to the next. This allows scientists to predict how well this vegetation will prevent erosion when rains start. Scientists can lay the satellite view of the vegetation over the topographic map and predict erosional patterns. This allows cities and towns to undertake erosion control measures. They may build retaining walls or plant more vegetation to prevent landslides from occurring.

In the past, topographers (map makers) had to travel to the area they were mapping to create a topographic map. Now with the use of satellites, scientists have been able to generate a complete digital topographic map of over 99% of Earth. The map was created using measurements from an instrument called ASTER, on NASA’s Terra satellite. This technology is much more accurate than the original way of creating topographic maps.

Being able to read topographic maps is a skill required in many careers. Geologists, architects, city planners, and engineers must all have this skill. Whether they are reading the older paper topographic maps or the newer digital topographic maps, these tools allow them to do their jobs well.

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6E5DE Weathering, Erosion, and Deposition

Reading Science 1.

How does a topographic map help an architect? A

It shows where to build a structure.

It shows how to build a structure.

It shows the elevation of a building site.

It tells the builder how the architect wants the parking lot.

How do plants help in erosion control? A

Plants’ roots hold the soil in place.

Plants are pretty and keep the neighborhood from becoming ugly.

Plants don’t help in erosion control.

Plants allow the soil to float in the rainwater.

Based on context of the passage, the term deposition means ______. A

laying down of sediments

erosion control

silt fences

landslides

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6E5DE Weathering, Erosion, and Deposition

Reading Science 4.

How do satellite views help scientists? A

They give scientists the ability to predict catastrophic events.

Satellite cameras are not good enough to really be helpful.

They allow scientists to know where valuable minerals are located.

They allow scientists to see changes as they happen.

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6E5DE Weathering, Erosion, and Deposition

Reading Science

These diagrams are topographic maps of Mount St. Helens in Washington state. They were made before and after the volcano erupted in 1980. What do these two maps tell us about the eruption? A

The eruption melted a glacier and caused massive flooding.

The eruption blew out the north wall of the volcano’s cone.

The eruption destroyed most of the surrounding forest.

The eruption did not change the shape of the volcano.

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6E5DE Weathering, Erosion, and Deposition

Math Connections Name:

Date:

Group:

The map shown below shows an island in the middle of the ocean. The elevations shown on the island are in meters (m).

Use the map above to answer questions 1–3. 1.

Draw a side view of what this island looks like based on the topographic map.

Explain how contour lines shown on a map are used to determine which area of the island has the steepest slope.

On the map provided above, shade in the entire area of the island that would be under water if the ocean rose 60 meters. What could cause this?

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Math Connections The Grand Canyon in Arizona may appear to never change to the human eye. However, the Colorado River is slowly eroding the Colorado Plateau, making the Grand Canyon grow deeper and wider. Use the information above to answer questions 4–7. 4.

Today the canyon’s deepest part is 5,500 m from the edge to the river. Assuming that it took about 5 million years to form at a constant rate, what was the rate of erosion in millimeters (mm) per year?

Use this rate of erosion to create an equation that can be used to calculate how many millimeters the canyon will grow in any number of years (y), where x represents the number of years.

Use your equation to solve for how many millimeters the canyon will grow from the year 2014 to the year 3000.

If the canyon is 5,500,000 millimeters in the year 2014, in what year will the canyon reach 5,500,011 mm in depth?

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6E5DE Weathering, Deposition, and Erosion

Math Connections 8.

The Ngilgi Caves are located in Yallingup, Western Australia. The limestone cave formed through the abrasive and corrosive effect of stream water. The cave is approximately 500,000 years old. The roof of the cave is full of stalactites, which are formed through the deposition of calcium carbonate and other minerals precipitated from mineralized water drops in the cave. The average growth rate of stalactites is 0.13 mm per year.

Use the information above to answer questions 8–10. 9.

Create an equation that can be used to calculate the height of a stalactite after any number of years.

10. How many years will it take to form a stalactite 1.3 m long?

11. If a stalactite was 110 cm long in 2014, in what year will it reach a length of 36 cm long?

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6E5DE Weathering, Erosion, and Deposition

Writing Science Name:

Date:

Group:

LOOK

THINK Think about the differences between erosion, weathering, and deposition. WRITE Decide whether the picture above is an example of erosion, weathering, deposition, or a combination of all three. Explain how you know.

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Writing Science

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6th Grade Earth and Space Science

6E5F

Plate Tectonics

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6E5F Plate Tectonics

Student Handout

Name:

Date:

Pictures A and B show the result when cars model convergent movement. What happens when two cars converge?

Draw arrows to show the direction of movement when the two cars in Picture C converge.

Define converge.

4. Picture D shows the result when two cars diverge. What happens when two cars diverge?

D 5.

Draw arrows to show the direction of movement when the two cars in Picture D diverge.

Define diverge.

Picture E shows the result when cars model transform movement. Describe the motion of the cars and what happens during transform movement.

raw arrows to show the D direction of transform movement for the cars below.

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6E5F Plate Tectonics

Student Journal Modeling Plate Movement You have created a model of two of Earth’s layers. Follow your teacher’s instructions to label the cross-section diagram of your model below using the words lithosphere and asthenosphere. The large cracker piece on the bottom does not need to be labeled.

CROSS-SECTION DIAGRAM OF MODEL

Figure 1: Draw arrows to show the direction of cracker movement in steps 5 and 6. Label the lithospheric plates. Label the asthenosphere.

1. Did your plates converge, diverge, or transform?

2. What do you feel as the sides of the crackers slide past each other?

3. What event might occur when plates move in this manner?

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6E5F Plate Tectonics

Student Journal Modeling Plate Movement, continued Figure 2: Draw a cross section of your model as it looks in steps 7 and 8. Add arrows to show the direction of movement. Label the lithosphere and the asthenosphere.

1. Did your plates converge, diverge, or transform?

2. What landform is created on the surface of Earth when plates move in this manner?

Figure 3: Draw a cross section of your model as it looks in step 9 and 10. Add arrows to show the direction of movement. Label the lithosphere and the asthenosphere.

1. Did your plates converge, diverge, or transform?

2. What do you see between the crackers on your model? What is exposed?

3. Is crust created or destroyed when plates move in this manner?

Figure 4: Draw a cross section of your model as it looks in steps 11 and 12. Add arrows to show the direction of movement. Label the subduction zone, the lithospheric plate containing oceanic crust, and the lithospheric plate containing continental crust.

1. Did your plates converge, diverge, or transform? 2. What leaked out when one cracker overlapped the other on your model?

3. When Earth’s material leaks through the crust, what kind of landform is created as plates move in this manner?

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6E5F Plate Tectonics

Student Journal Background Information 1.

What events occur when the tectonic plates move and grind against each other?

Name a location where divergent boundaries occur.

Name a location where convergent boundaries occur.

Name a location where transform boundaries occur.

What is the Ring of Fire?

Which layer of Earth is semi-plastic, flows, and carries the lithosphere of Earth?

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6E5F Plate Tectonics

Student Journal Reflections and Conclusions 1.

What are the major tectonic plates?

What are the different ways tectonic plates move in relation to each other?

What landforms could be the result of diverging plates?

What landforms could be the result of converging plates?

What major event could occur as the result of transforming plates?

If crust is constantly created at divergent boundaries, why is Earth not getting larger?

An area with many volcanoes that includes the western borders of South, Central, and North America, the southern border of Alaska, and the eastern border of Japan is often called the Ring of Fire. Why did so many volcanoes form in this area?

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STEMscopedia: PLATE TECTONICS 6E5F Reflect Have you ever watched a Hollywood disaster movie and wondered if such a disaster could really happen? Many of these types of movies center on mega-volcanoes, overly gigantic tsunamis, or other geologic events related to plate tectonics. Plate tectonics is a scientific theory that states that Earth’s solid, rocky lithosphere is broken into pieces called tectonic plates (also known as lithospheric plates).

If you’ve ever noticed how the continents appear to fit together like a jigsaw puzzle, you’re not alone. In the early 20th century, a German scientist named Alfred Wegener noticed this phenomenon. Wegener hypothesized that at one or more points in Earth’s history, the continents were connected. Wegener looked for further evidence that the continents may have once been connected. He looked for other connections between the matching coastlines. Where coastlines appeared to fit together, Wegener noticed that certain geologic formations also appeared to fit together. For example, a mountain range on one coastline appears to connect with a mountain chain on the opposite coastline. Several deposits of sediments left behind by glaciers also line up along the matching coastlines of continents. Wegener also found many fossils that supported his theory. Wegener concluded from his findings that the continents must move over time. He called this hypothesis continental displacement. (Later scientists gave the process its more familiar name, continental drift.) At least once in Earth’s history, the continents were connected in large land masses. These large land masses are called supercontinents. All the continents were connected as one giant supercontinent 250 million years ago. Wegener named this supercontinent Pangaea, which means “all Earth.”

topography: the physical features of an area

Because Wegener had only pieces of evidence but no proof, his theory was not widely accepted. It wasn’t until the 1940s, when technology allowed scientists to further research the ocean floor, that his discoveries were taken seriously. Scientists began to realize the crust beneath oceans is not as old as the crust beneath continents. They also learned the ocean floor is not flat and barren. Instead, it contains many topographic features. In fact, one of the largest mountain ranges in the world is at the bottom of the ocean. This mountain range, the mid-ocean ridge, is made up of two parallel mountain chains separated by a central valley. It is 50,000 kilometers long and an average of 4,500 meters tall.

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STEMscopedia: PLATE TECTONICS

The movement of the continents has taken millions of years.

Scientists discovered other information about the ocean floor as well. For example, sediments at the bottom of the ocean had been building up for a maximum of only 300 million years. If the ocean floor had not changed throughout Earth’s history, these sediments would be about four billion years old. Similarly, the oldest fossils on the ocean floor are only about 180 million years old. Marine fossils buried in Earth’s continents are thought to be much older. Scientists realized that some process must be destroying older sediments and fossils on the ocean floor. Because rocks and fossils on the continents are much older than those on the ocean floor, this process must affect oceanic crust differently than continental crust. If oceanic crust is being destroyed, where do you think it goes? What happens to the crust after it is destroyed? Where does new crust come from? Think about these questions, and then read on to learn the answers! Scientists in the Spotlight: Harry Hess and Seafloor Spreading Harry Hess was a geologist who served in the U.S. Navy during World War II. Hess used some of the Navy’s ocean exploration technology to study the mid-ocean ridge and other ocean features. In the 1950s and early 1960s, Hess used his research of the ocean floor to develop a hypothesis called seafloor spreading. Seafloor spreading is a phenomenon by which magma from Earth’s mantle—the layer beneath the crust—wells up between the central valley of the mid-ocean ridge. When the magma pushes up through the center of the mid-ocean ridge, it forces the ocean floor apart. This breaking apart of the crust is called rifting. When the magma reaches the surface of the ocean crust, it cools and solidifies into igneous rock. This makes new oceanic crust in the center of the mid-ocean ridge. Hess also reasoned that older crust is destroyed as it sinks into deep ocean basins. Seafloor spreading explains why oceanic crust is younger than continental crust. Oceanic crust is continually being recycled.

Cross-section diagram showing seafloor spreading.

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STEMscopedia: PLATE TECTONICS Hess had better luck than Wegener. He lived long enough to see his hypothesis validated by further scientific evidence and accepted by the scientific community. In the process, Hess finally provided the explanation that Wegener lacked for his continental drift hypothesis. Continents are dragged along Earth’s surface by the motion of oceanic crust as it is recycled.

Look Out Earth is composed of several layers. The center of Earth is a solid sphere, composed mostly of iron and nickel, called the inner core. This is surrounded by a liquid outer core, once again mostly iron and nickel. The next layer is called the mantle. This is the thickest layer and comprises most of the mass of Earth. The mantle is where the magma in volcanoes comes from. The top of the mantle is special because it has a physical property called plasticity. This means it can flow very slowly, like Silly Putty™. The crust (the thin, outermost layer of Earth) rests on top of this slowly moving layer. The crust and the very top part of the mantle create the lithosphere layer. The lithosphere is broken into chunks called tectonic, or lithospheric, plates. The plates can be composed of oceanic crust, continental crust, or both. The plates do not move themselves, nor are they floating on top of the ocean. Oceans are Important: The lithospheric not underneath the continents! plates are solid rock. The plates are floating on top of Water, trees, soil, and the asthenosphere (upper part animals all rest on top of of the mantle). The motion of the these slabs of rock. magma in the asthenosphere from convection currents causes the plate movement. Heat transfers from the core to the mantle. As the material in the mantle heats up, it becomes less dense and begins to rise, traveling from the bottom of the mantle (by the core) up toward the top of the mantle (by the crust). This material is moving very slowly! As it moves away from the heat of the core, upward toward the crust, it begins to cool down. Cooling down causes the material to become denser, so it begins sinking back toward the core again. This rising and falling of mantle material is called a convection current. Convection currents cause the movement of the plates.

The arrows show direction of movement. Convection currents create circular patterns. The way the magma moves below the plate determines the direction the plate will move.

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STEMscopedia: PLATE TECTONICS The Theory of Plate Tectonics As tectonic plates move, they rub against each other. These movements cause earthquakes. Earthquakes can occur anywhere tectonic plate activity happens. Tectonic plate movements also create openings in Earth’s crust where magma can reach the planet’s surface. We call these openings volcanoes. By mapping the locations of earthquakes and volcanoes, scientists have been able to locate the boundaries of Earth’s tectonic plates. Tectonic Plate Boundaries Tectonic plates are constantly moving at different rates and in different directions. They interact with each other in different ways. This results in different types of tectonic plate boundaries. Tectonic plate boundaries can be separated into the following three categories: convergent, divergent, and transform. plate boundary: the area where two plates are interacting Convergent Plate Boundaries: At these boundaries, tectonic plates move toward each other, or converge. This motion destroys crust. • When plates of continental crust come together, they can push up the land over time. Continentalcontinental collisions create large folded mountain chains, such as the Himalayas. These mountains were created millions of years ago when the Indo-Australian plate collided with the Eurasian plate.

Convergent continental-continental boundary •

When plates of oceanic crust collide, they can create a subduction zone. A subduction zone is a convergent boundary where the denser of the two plates is pushed beneath the other. Eventually, the denser plate is pushed far enough into the mantle that it begins to melt. At an oceanicoceanic collision, a trench and a volcanic island will typically form. Volcanoes are common around subduction zones as crust melts into magma.

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STEMscopedia: PLATE TECTONICS •

Subduction zones also form where oceanic crust collides with continental crust. Because oceanic crust is denser, it is always subducted beneath continental crust at a subduction zone. Continental-oceanic collisions usually cause a trench and a volcanic mountain to form

Convergent oceanic-continental boundary with subduction zone Divergent Plate Boundaries: At these boundaries, tectonic plates move away from each other, or diverge. This creates new crust. • A mid-ocean ridge forms at a divergent boundary between two plates of oceanic crust. Magma rises up between the plates, then cools to form new oceanic crust. The formation of new oceanic crust helps to further push the two plates apart. • Rift valleys form when continental crust diverges. One of the biggest examples of a rift valley is the East African Rift Valley.

Rift valley Divergent oceanic-oceanic boundary Transform Plate Boundaries: At these boundaries, tectonic plates slide horizontally past each other in opposite directions. While all three types of boundaries create faults (cracks in Earth’s crust), transform boundaries create strike-slip faults. The San Andreas Fault is an example of a strike-slip fault. It cuts across the state of California and is a transform boundary between the Pacific plate and the North American plate. When tectonic plates slide against each other at transform boundaries, pressure builds up until the plates suddenly slip. This sudden release of pressure causes an earthquake. This release of pressure can also allow magma to come up from the mantle, which can sometimes result in a volcanic eruption.

Fault line Transform continental-continental boundary

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STEMscopedia: PLATE TECTONICS Hot Spots: The majority of volcanoes are located at plate boundaries. However, there are volcanoes that exist far away from any known plate boundary. These are called hot spot volcanoes. Hot spots are weak areas in the crust where magma can come to the surface. Hawaii is an example of a hot spot.

Volcano cross section

Try Now To better understand the asthenosphere’s physical property of plasticity, try this. Take a piece of Silly Putty™ and roll it in your hands until it forms a sphere. Let the sphere rest on a flat surface for 5 minutes. Gently pick it up and look at the bottom. Is it still a sphere shape? No, the bottom has flattened out. This is because the Silly Putty™ has the physical property of plasticity. This allows the putty to slowly ooze and spread. This slow movement is the same way the magma flows in the asthenosphere.

What Do You Think? Match the geologic features with the type of plate movement that creates them. Some features may occur at more than one type of boundary. _____ 1. Volcanic island A. Convergent boundary _____ 2. Trench _____ 3. Rift valley _____ 4. Earthquake B. Divergent boundary _____ 5. Volcanic mountain _____ 6. Folded mountain _____ 7. Mid-ocean ridge C. Transform boundary _____ 8. Strike-slip fault

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STEMscopedia: PLATE TECTONICS Connecting With Your Child Since we cannot see the inside of Earth to watch the convection currents happen, we have to replicate the effects using a model. A lava lamp is a good example of a convection current. When you turn on the lamp, the “lava” heats up. As it heats up, its particles move faster and spread out. This causes the material to become less dense than the fluid it is in, and it rises to the top. At the top, away from the heat source, the “lava” begins to cool down. As it cools down, its particles slow down and move closer together. This makes it once again denser than the surrounding fluid, so it sinks. As it gets closer to the heat source, the cycle continues. This rising and falling is a convection current! Create your own convection current model using the following materials: • 4 Empty 20-ounce bottles (Soda bottles work great!) • Water • 2 Colors of food coloring • Index card 1. Fill two of the bottles with hot water. (Be careful! It doesn’t have to be boiling. Hot water from the tap is fine.) Fill the other two bottles with cold water. The water needs to go all the way to the top. 2. Using five drops of food coloring per bottle, color the hot water one color and the cold water a different color. 3. Place the index card over the mouth of one of the hot water bottles and invert it over the mouth of one of the cold water bottles. The mouths should be directly over one another. 4. Slip the card from between the two bottles and observe the interaction between the hot water and the cold water. 5. Now, do the same thing in reverse. Place the card over the remaining cold water bottle and invert it over the remaining hot water bottle. 6. Slip the card from between the two bottles and observe the interaction between the cold water and the hot water. Questions to discuss together: • How did the water interact the first time? • How did the water interact the second time? • How does this demonstration compare to convection currents in the mantle?

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6E5F Plate Tectonics

Reading Science Name:

Date:

Group:

Tectonic Plates 1

On March 11, 2011, an earthquake measuring 8.9 on the Richter scale rocked the seafloor. It made a giant wave, which grew as tall as 30 feet (9.14 meters) high. The huge ocean wave, called a tsunami, sped toward the coast of eastern Japan. It hit the coast, tearing apart buildings and homes, and flooding rice fields. The tsunami also took human lives with it.

Sadly, this wasn’t the first time that a disaster like this has happened in the world. It won’t be the last time either. Over Earth’s history, tectonic plates have always moved. This movement has reshaped continents, created and destroyed ocean basins, and caused earthquakes. Tectonic plate movements have also formed a variety of landforms. These include volcanoes, mountain ranges, and oceanic trenches. To find out how and why these things happen, Earth scientists have studied the movement of plates.

Earth is made of three different layers: crust, mantle, and core. The crust and the thin, solid upper section of the mantle together form the lithosphere. Under the rigid lithosphere is a section of the mantle called the asthenosphere. The asthenosphere is soft and putty-like. The lithosphere is broken into separate pieces, much like a cracked eggshell. These pieces are called plates. There are seven major tectonic plates. North of the equator are the Eurasian and North American plates. Most or all of the South American, Indo-Australian, and Antarctic plates lie south of the equator. The equator crosses the middle of the Pacific and African plates.

The plates glide on the flexible asthenosphere. They creep along moving in different directions and at different speeds. Plates move toward (or away from) one another very slowly. They may move from less than 1 cm per year to as much as 10 cm per year. This top speed is about as fast as fingernails grow. Because plates move in different directions, there is a lot of tearing and crunching where any two plates meet. Thus, scientists research plate boundaries to understand tectonic movement.

There are three types of plate boundaries: divergent, convergent, and transform. Boundary type is based on the way the plates move compared to one another. Different landforms result from different boundary types. Different sets of events, such as earthquakes, tsunamis, or volcanic eruptions, can happen at each boundary. What the plate is made of is also important. The plate could be made of denser ocean basin rock or of less dense continental rock. The landforms and types of events that result depend on the direction of motion and the types of plates.

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6E5F Plate Tectonics

Reading Science Continued 6

Divergent boundaries occur when two plates pull away from each other. When this happens, a rift or tear is made in the lithosphere. Magma from the asthenosphere seeps up through the rift. As magma cools, new crust is made. The new material builds up along the rift. It forms volcanic ridges or individual volcanoes. This type of boundary is found in the Mid-Atlantic Ridge. This type of boundary can form a new ocean.

Convergent boundaries occur when two plates run into each other. When both are made of continental rock, the land is pressed together and pushed upward. This can form massive mountain ranges like the Himalayan Mountains. It is different if one or both of the plates are made of dense oceanic rock. In that case, the denser plate will plunge under the other. This is how deep ocean trenches are made. Volcanic mountain chains can form as some of the plunging plate heats up and melts. This is the type of boundary found along the coast of Japan.

Transform boundaries occur when two plates slide horizontally past one another. Transform boundaries are different than the other boundary types. They do not usually form mountains, volcanoes, or trenches. However, movement along transform boundaries can trigger earthquakes. The San Andreas Fault in California is a transform boundary. There have been many San Andreas earthquakes. These have resulted in a great loss of life and property over history. Transform faults are also found in ocean basins as part of mid-oceanic ridge structures.

The broken pieces of Earth’s plates are like a patchwork quilt in motion. Over the past 50 years, Earth scientists have learned many basic principles of tectonic plate movement. They can better explain the way that Earth’s crust has changed over time. Scientists also understand more about how plate movements can result in earthquakes, tsunamis, and volcanic eruptions. Scientists still must learn more before they can predict these events before they happen.

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6E5F Plate Tectonics

Reading Science 1.

What is the difference between a divergent boundary and a convergent boundary? A

Divergent boundaries slide past each other horizontally, and convergent boundaries form mountain ranges and ocean trenches.

Divergent boundaries run into each other, and convergent boundaries pull away from each other.

Divergent boundaries pull away from each other, and convergent boundaries run into each other.

Divergent boundaries form mountain ranges, and convergent boundaries slide past each other horizontally.

Which of the following statements best summarizes the main points of the passage? A

There are three types of plate boundaries: divergent, convergent, and transform.

In 2011, an earthquake measuring 8.9 on the Richter scale shook the ocean floor. It made a giant wave that grew up to 30 feet (9.14 meters) tall.

Tectonic plates have always moved and always will.

Scientists study plate boundaries to understand tectonic movement and more about how plate movements can result in earthquakes, tsunamis, and volcanic eruptions, and to explore how to predict these events.

If a convergent boundary involves a continental landmass and an ocean basin, what is the result? A

A chain of volcanic mountains will form on the edge of the continent or just offshore; a deep ocean trench will form offshore.

The land will fold and fault forming high mountain ranges.

The land at the edge of the continent will buckle causing the formation of a trench.

There will be frequent earthquakes but no other evidence of crustal movement.

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6E5F Plate Tectonics

Reading Science 4.

Which statement can be made about the passage? A

Scientists can predict earthquakes but not tsunamis.

Tectonic plates have moved and reshaped continents, created and destroyed ocean basins, and caused earthquakes.

Meteorologists can broadcast news quickly about approaching disasters.

Shifting of tectonic plates never affects people’s lives.

Examine the diagram above. Which are the correct labels for continental plates 1 and 2? A

1=Antarctic, 2=African

1=Indo-Australian, 2=Eurasian

1=North American, 2=Pacific

1=South American, 2=Antarctic

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6E5F Plate Tectonics

Math Connections Name:

Date:

Group:

Spreading Rates As the plates move and form mid-ocean ridges, this causes the ocean floor to spread. As it spreads, magma from the mantle surfaces and solidifies to create new lithosphere. Scientists can measure the spreading rate of the ridges using maps of the sea floor over time. The spreading rate is calculated by dividing the distance of the spread by the time it took to spread: R = d/t R = rate of seafloor spreading d = distance between two points on the map t = difference in time between two points on the plates 1.

If a segment of the East Pacific Rise spreads 748 km over a span of 18 million years, what is the rate of spreading in one year? Convert your answer to centimeters per year. (Round to the nearest hundredth.)

Use the answer from question 1 to determine how far the sea floor will spread in the next 50 years. What type of geological events could this cause in the region?

If a segment of the Mid-Atlantic Ridge spreads 927 km over a span 71 million years, what is the rate of spreading in one year? Convert your answer to centimeters per year. (Round to the nearest hundredth.)

Use the answer from question 3 to determine how far the sea floor will spread in the next 150 years.

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6E5F Plate Tectonics

Math Connections 5.

If the rate of seafloor spreading between two plates is 2 cm/year and the time passed is 54,000,000 years, how many kilometers has the sea floor actually spread?

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6E5F Plate Tectonics

Writing Science Name:

Date:

Group:

LOOK

THINK Think about how the lithosphere is divided into plates that are constantly moving. WRITE Explain why the plates move and how they contribute to major geological events and features that make up Earth’s surface. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E5F Plate Tectonics

Writing Science

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6th Grade Earth and Space Science

6E5G

Fossil Evidence Of A Changing Earth

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6E5G Fossil Evidence of a Changing Earth

Student Journal Name:

Date:

Group:

Digging Through the Past 1.

Order the layers from oldest to youngest using the meter depth (six lines).

Depth (___m)

Names of Organisms

Rock Type

Habitat

Select two fossil layers. Record the depth of each. How are these environments different? Did this difference affect the type of fossil you found in each layer?

How can we use fossils found in rocks to identify the age of the rocks?

Why might you find fossil evidence of both an ocean and a forest at different depths in the same location?

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Reflect

6E5G

Seashells seem to be everywhere. Most of the time, you will find them on beaches. But every now and then, you might find them far from the sea. For example, you might find a shell stuck in a rock high on a mountain. What might your find tell you?

How can fossils tell us which organisms lived millions of years ago? Fossils are preserved parts or traces of animals or plants that lived in the past. Fossils are clues to the past. They tell us what organisms lived in a certain place. They can tell us what the organism looked like. They can tell us what the environment was like in the place where the organism lived. Fossils can also tell us how organisms have changed over time. If you find fossils of seashells high in a mountain, you might be able to conclude that the mountain used to be underwater at some point in the past.

Fossils do not have dates printed on them. Yet scientists have ways to tell two things about the organisms that became the fossils. Scientists can figure out the order in which the organisms lived on Earth. Scientists can also calculate when the organisms lived on Earth using particles around or in the fossil. Figuring out the order is relatively simple. Look at the photo on the right. It shows layers of rock. The layers of rock were formed one on top of the other. The bottom layer was laid down first. So it is the oldest layer. The top layer was laid down last. So it is the youngest layer. The layers in between are younger and younger from bottom to top.

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Imagine that you baked layers of a cake on Monday, Tuesday, Wednesday, and Thursday, and you put each layer on top of the other on the day it was baked. The Monday layer would be at the bottom. The Tuesday layer would be on top of the Monday layer. Wednesday’s layer would come next. And, finally, you would put Thursday’s layer on top. Monday’s layer would be the oldest. Thursday’s layer would be the youngest. Now, let’s take this a step further. Let’s say you put walnuts in Monday’s layer. You put raisins in Tuesday’s layer. You put cranberries in Wednesday’s layer. And, finally, you put chocolate chips in Thursday’s layer. You give the cake to a friend, who knows that the bottom layer is oldest and the top layer is youngest. What could your friend conclude about the ingredients? He could conclude that the walnuts were added first because they are in the oldest layer. He could conclude that the raisins were added second because they are in the second oldest layer. He could conclude that the cranberries were added third because they are in the third oldest layer. And he could conclude that the chocolate chips were added last because they are in the youngest layer. What has this got to do with the age of fossils? Think of the walnuts, raisins, cranberries, and chocolate chips as fossils. The rock layers in which fossils are found tell the order of the ages of the fossils. Fossils in the bottom layer are older than fossils in higher layers. Scientists also have ways to find the actual age of fossils. One way to find the actual age of a fossil is to find the age of the rock layer in which the fossil is found. This makes sense because the organism that produced the fossil was trapped in the rock when it formed. How long ago did the last dinosaurs become extinct, or die out forever? The youngest dinosaur fossils are found in rock layers that are about 65 million years old. Therefore, we can use that evidence to conclude that dinosaurs became extinct about 65 million years ago. You may be wondering how scientists figure out the actual age of rock layers and fossils. The process is a bit complex. But if you are curious, do an Internet search using the keywords “radioactive dating.”

Evidence from fossils shows that dinosaurs became extinct 65 million years ago.

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What Do You Think? Take a look at the illustrations on the right. They show fossils found in different layers of rock. What is the order of these fossils from oldest to youngest? How can fossils tell us what environments were like millions of years ago? Scientists tell us that environments change over time. However, what evidence have they found to back up this claim? Here are two answers. In 1988, Gordon Hubbell and a team of fossil hunters dug a hole in a desert in Peru. Today, this desert is one of the driest places on Earth. Almost no rain falls there. Hubbell is an expert in fossil sharks. After digging for a while, Hubbell discovered a jawbone and more than 200 sharp teeth. The teeth were shaped like triangles. Hubbell recognized the teeth. They belonged to the ancestors of one of the fiercest animals in the sea: the great white shark. For about 20 years, the teeth were stored in Hubbell’s collection of fossils. Then, in the early 2000s, another team of scientists decided to examine the teeth. Bruce MacFadden of the Florida Museum of Natural History in Gainesville, Florida, led the team. MacFadden and his team were able to figure out the age of the fossil teeth. They were four million years old! The conclusion? Four million years ago, one of today’s driest places was underwater. Fossils had proved that the environment in this place greatly changed over time. Here is another example. Today, the continent of Antarctica, which surrounds Earth’s South Pole, is the coldest place on our planet. Temperatures there can dive below –84 degrees Celsius (–120 degrees Fahrenheit). No plants or animals make their homes permanently in the interior of Antarctica. But was Antarctica always this cold and empty of living things? According to fossil evidence, the answer is no. Scientists exploring an area in Antarctica called the Dry Valleys have found fossils of mosses and tiny animals. The fossils were unearthed in ancient lakebeds. The scientists calculated that the fossils were about 14.1 million years old. At that time, shrubs grew from the ground around the lakes. Some insects lived there, too. To support such living things, summer temperatures would have had to be much warmer than they are now. Again, fossils proved that an environment on Earth had changed greatly over time.

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Look Out Not all parts of an ancient organism can form a fossil. Fossils are most often formed from the hard parts of organisms. The soft parts usually break down before they can be preserved in rock. However, there are exceptions. For example, animals trapped under ice may be preserved whole. This is what happened to some woolly mammoths, like the one shown in the top image at right. Woolly mammoths are extinct animals that looked a bit like modern elephants. Some lived in the icy regions close to the North Pole. Some insects are preserved whole, too. This is especially true of insects trapped in tree sap. When the sap hardens, the insect is preserved inside. This happened to the mosquito in the bottom image at right. How can we represent fossils and past environments using models? Scientists often use models to describe objects or events in nature. A model is a representation of a real thing. A model may be as simple as a drawing. It may be a shape made out of clay. It may be an animal reconstructed from just a few fossil bones. The dinosaur skeleton shown at left is used to make a model of a complete dinosaur.

A model may also be a diorama displayed in a natural history museum. A museum diorama often shows a model of both an organism and its environment. The environment may be in the present. It may also be in the distant past. The American Museum of Natural History in New York City holds an example. It shows two organisms related to human beings. They are walking on a dusty plain in Africa. This model was based on actual fossil footprints left behind by the organisms and preserved in rock. By using the shape of the footprint, scientists can draw conclusions about the body shapes and sizes of those organisms that made the prints.

Try Now Collect a variety of small objects. These may be natural objects, such as stones or leaves, or they may be human-made objects, such as coins or marbles. Make an imprint of each object by pressing one side of the object into a piece of modeling clay. These imprints represent fossils. Label each imprint with a number, and create a key identifying the object that produced each imprint. For example: “Number 1: leaf from maple tree.” Ask your classmates to try to identify the source of each “fossil”—that is, the object that made each imprint. Ask your classmates to explain how they came up with their answers.

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Discover Science: What “Lucy” Tells Us In 1974, fossil hunters working in Africa discovered the almost complete skeleton of an organism related to human beings. Scientists determined that the skeleton belonged to an adult female. They also were able to calculate that she lived a little more than three million years ago. They named the skeleton “Lucy.” Studies of Lucy’s bones revealed a number of things about her. She was less than 1.1 meters (3.5 feet) tall. And she probably weighed fewer than 30 kilograms (66 pounds). But most importantly, her bone structure provided evidence that she walked upright. Fossil footprints, also found in Africa, further support this conclusion. The footprints belonged to other members of Lucy’s group of organisms. The footprints clearly showed two organisms walking much as we do today. As far as scientists know, Lucy and her kind were the first humanlike organisms to walk upright.

What Do You Know? The following chart lists five different locations on Earth today. Suppose that scientists find a fossil of an ancient organism in each location. Based on the type of fossil found there, decide how the location has changed over time. In particular, decide whether each location: • Used to be a forest • Used to be underwater • Used to be a tropical island • Has not changed since the fossil was formed Write your answers in the third column of the chart. Fossil

Where was it found?

Sea shell

The side of a mountain

Palm branch

An ice sheet in the Artic

The imprint of a cactus leaf

A desert

Insect trapped in sap

Under the ocean floor

Shark tooth

Wide open grassland

How has the location changed?

The following diagram shows three layers of a hillside. What can this diagram tell us about the hillside?

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Connecting With Your Child Fossil Safari There are a number of ways to give students a firsthand experience with fossils. If your community, or a nearby community, has a museum of natural history, be sure to visit exhibits that contain fossils or organisms reconstructed from fossils. Alternatively, arrange for a visit to a local college or university where fossils are kept. Check with the geology and biology departments, which are most likely to keep collections of fossils. In either case, try to arrange a visit with a curator or an educator who could identify a particular fossil and explain where it was found and how it is significant. You might ask your child to prepare for such an experience by making a list of questions concerning fossils. Here are some questions to discuss with your child: 1. What is a fossil? 2. What parts of ancient organisms are most likely to become fossils? 3. In what materials are most fossils found? 4. If you found two different fossils, what is one way you might be able to tell which one is older? 5. What can a fossil tell you about ancient organisms? 6. What can a fossil tell you about the surrounding land? 7. What is the oldest known fossil? 8. How can fossils teach us about weather change?

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Reading Science Name:

Date:

Group:

Lone Star Dinosaur 1

Long ago, a female dinosaur was looking for food by a streambed in what would someday be known as the state of Texas. She had been traveling with a group of other dinosaurs that decided it was time to stop for food. The young dinosaurs searched for plants close to the streambed while the adults formed a circle around them. That way they would be protected from any predators that might be nearby. They soon found what they wanted and left. When they left, they left behind tracks in the soft mud of the streambed.

These footprints were not disturbed for a long time. About 110 million years later, scientists found the tracks near Glen Rose, Texas. They found bones nearby too. Scientists studied these tracks and bones, and they named the dinosaur Pleurocoelus (PLOOR-oh-SEEL-us). Later, they also found the tracks of another dinosaur. That one seemed to have been chasing the Pleurocoelus!

Of course, it is hard to know for sure what happened. This is because scientists could not observe a living dinosaur to see what it ate or how it behaved. There are special scientists called paleontologists. They are able to use clues left behind by dinosaurs to infer what the dinosaurs’ lives were like.

For example, the tracks left in the mud tell scientists much about the animals who made them. The size of the footprint can tell the scientists approximately how big the dinosaur was. The distance between tracks can tell them whether the animal was running or walking. The number of footprints in an area can tell them whether the animal lived alone or in a group.

Paleontologists used other clues to figure out what dinosaurs ate. The Pleurocoelus, for example, had weak teeth. This tells scientists that the animal was an herbivore, or plant eater. It did not need strong and sharp teeth like those of a meat-eating carnivore.

From these bones and tracks, paleontologists have been able to create a pretty good picture of the Pleurocoelus. For one thing, they can tell that it was a quadruped. This means that it had four legs. Another thing they can tell is that a female might have weighed close to 20 tons. That is about the same as 10 small cars! They also know that the female’s front legs were longer than her back legs. They also know that she had a small, narrow head on a long neck—just like a giraffe’s. But unlike a giraffe, she had a bulky body and a long tail.

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Reading Science Continued 7

Because of the many tracks and bones of Pleurocoelus found in Texas, the state passed a bill that made Pleurocoelus the official Lone Star State Dinosaur. Today, the place on the streambed where the tracks were left is part of Dinosaur Valley State Park, where visitors can see the footprints for themselves. In fact, this park is one of the best places to see dinosaur tracks. You should call before you go to visit because the tracks are in the riverbed. This means that you will not be able to see them when the river is too high.

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Reading Science 1.

Which of the following is NOT TRUE of Pleurocoelus? A

It had weak teeth.

It had a long neck.

It had four legs.

It did not have any predators.

How did the scientists know the carnivore was chasing Pleurocoelus (paragraph 2)? A

The carnivore tracks came behind the Pleurocoelus tracks.

The carnivore’s teeth were found near the Pleurocoelus.

The Pleurocoelus was protecting its young.

The carnivore was small.

Why did the author probably write this passage? A

To tell a story about a mother dinosaur

To describe how clues from fossils can tell us about the past

To persuade the reader that the Pleurocoelus should be the state dinosaur

To give information about Dinosaur Valley State Park

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Reading Science 4.

Which of the following is a quadruped (paragraph 6)? A

A human

A parrot

A horse

A tree

What is something a paleontologist probably would not do? A

Look at fossilized bones

Try to use dinosaur tracks to find out what the dinosaur weighed

Hide fossils so no one else could find them

Measure the distance between dinosaur tracks

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Math Connections Name:

Date:

Group:

Models can be used to represent the passage of time and past organisms and environments. The table below shows a portion of the chart used for figuring out the numerical age and the name of the time period for a fossil or rock. The numerical age is measured in how many millions of years before present time (Ma) that fossil or rock took to form. International Chronostratigraphic Chart Era

Period

Epoch Holocene

Quaternary

Stage

Pleistocene

Cenozoic Piocene Neogene Miocene

Upper Middle Calabrian Gelasian Piacenzian Zanclean Messinian Totonian Serravallian

Numerical Age (Ma) Present 0.0117 0.128 0.781 1.80 3.60 5.333 7.246 11.63 13.82

1. How many millions of years older would a fossil from the Serravallian stage be than from the Piacenzian stage? Ma 2. Express the numerical age of the Middle stage in the Pleistocene epoch using expanded notation: +

3. If a fossil’s age was found to be eleven and sixty-three hundredths Ma (million years before present), what period and epoch was it from? Period:

Epoch:

4. Compare the numerical age of the Cambrian stage to the Middle Pleistocene stage using the symbol <, >, or = in the circle below. 5. A rock layer from the Zanclean stage was located in Eraclea Minoa, Sicily, Italy. Multiply its numerical age by 1,000,000 to figure out the standard representation of its age. years before present time © Accelerate Learning Inc. - All Rights Reserved

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Writing Science Name:

Date:

Group:

READ Read the information in the box. Fossils are the preserves, remains, or traces of organisms that lived many years in the past. Fossils can be preserved body parts, such as bones, or they can be traces of organisms, such as footprints. Fossils are not part of the organism itself. The organism is actually replaced with other substances, such as rock, and preserved. Scientists can use fossils to interpret past events and environments. This allows them to create models to represent the passage of time. THINK Think about this rock slab that was found on the construction site of a new underground parking garage. What do you think the land was like at that site millions of years ago? WRITE Explain the ways you think this fossil could have been formed. What geological story do you think it tells? Be sure to • clearly state your central idea; • organize your thoughts logically; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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Writing Science

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6th Grade Earth and Space Science

6E5H

Soil Composition

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Student Journal Name:

Date:

Group:

Part I: Forming Soil Complete the chart by following the directions in your Student Guide. Starting Mass

Mass 2 Min. After Shaking

Mass 4 Min. After Shaking

Mass 6 Min. After Shaking

Mass 8 Min. After Shaking

Rock A Rock B Using the data you recorded in the above chart, make a graph of the mass of each rock. You will first label the amount in grams on the left side of each graph.

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Student Journal Part I: Forming Soil, continued Which rock do you think would break down the fastest over time?

What outside factors could possibly influence the weathering of rocks?

Observe: Draw and record what you see on the plate. Soil is made of:

Part II: Forest and Delta Observe the forest and delta soil pictures. What are some similarities?

What are the differences between the soils? Why do the differences exist?

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Student Journal Part III: Weathering, Erosion, and Deposition Modeling the Formation of Soil What does the candy represent?

Chewing represents

Swallowing represents

The bits that settle in the stomach represent

Observe: Draw and record what you see on the plate. Reflection: Explain some forces in nature that could cause weathering.

Give an example of a place where weathering has occurred in your area.

What are the parts of soil? How did they get there? Soil Part

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How Did It Become Soil?

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STEMscopedia: SOIL COMPOSITION 6E5H Reflect Soil is everywhere. We find soil in our yards, underneath our buildings, on mountainsides, and even on the ocean floor. All of Earth’s plants grow in soil. Consider all the ecosystems of the world. Is soil the same in every environment? If you’ve ever taken a trip even just a few hours from home, you have probably noticed that all soil is not the same. Different types of soil have different properties. What do you think causes soil to be different from place to place? What Is Weathering? The process of Earth’s rocks and minerals being broken down into smaller pieces is called weathering. Weathering occurs through the work of both physical and chemical forces.

Rock is weathered into different size soil particles.

Physical weathering breaks rocks into smaller pieces by wind, water, or ice. Traces of the original minerals can be found in the weathered rock, they are just smaller particles. Chemical weathering also breaks rocks into smaller pieces; however, during chemical weathering, a chemical reaction takes place changing the original properties of the rock. This means that the original minerals and rock are transformed into a different kind of rock.

The Colorado River slowly broke down rock to form the Grand Canyon.

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STEMscopedia: SOIL COMPOSITION What Is Soil Made Of? Both types of weathering break down rocks into smaller pieces. These smaller particles make up soil. Different soils have different colors and textures, and they are made of different minerals. As different rocks and minerals are broken down by weathering, different soil types are formed. Look at the picture to the left. Most of the rocks and the soil surrounding the rocks are red. The soil contains weathered rocks that contain red minerals. Rocks are broken down into smaller pieces that make up soil. What Else Is Soil Made Of? Soil is not only made of rock particles, it is also made of other substances important for plant growth. Plants need nutrients to survive that are not found in rocks. The organic material found in soil is necessary for plants to thrive. Where does this organic material come from? Most of this nutrient rich material is recycled from dead plants and animals. Over time, dead plants and animals decay and decompose.

Organic material: remains of living organisms such as plants and animals as well as their waste products

As plants and animals decompose, they break down into smaller and smaller pieces that then become part of the soil. As they decompose, they release nutrients into the soil. For example, all plants and animals contain carbon, an element necessary for plant growth. Another important nutrient in soil is nitrogen. Animal waste is an excellent source of nitrogen, which is why farmers and gardeners use manure to fertilize and enrich their soil.

Soil is more than just small pieces of rock. It is also made up of decomposed plant and animal remains that add nutrients to the soil.

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STEMscopedia: SOIL COMPOSITION Look Out Manure is not the only type of fertilizer that farmers use. Some fertilizers are made of chemical mixtures. These chemicals provide nitrogen and other nutrients to the soil. However, using an excess of chemical fertilizers can pollute the environment. When it rains, the extra chemicals may wash into nearby streams or ponds. Many farmers are using organic methods to protect our water sources and our health, but many large farms are still using chemicals to enhance the soil. How Are Soils Different in Different Areas? Soil types are different in different areas, even within a few miles of each other. Some soils contain high amounts of organic material from decomposed matter, like carbon and nitrogen. Soils high in organic matter contain lots of nutrients, so these soils are good for growing plants. Some soils contain mainly inorganic matter, or materials from things that were never alive. These soils are made of mostly rock. Soils are classified by the texture of the types of particles they contain. You can observe these particles yourself and try to classify soil. If soil feels rough, the soil is likely sand. If the soil feels sticky, it might contain clay. Clay usually has very small particles. If the soil feels smooth, it is silt. Loam soils contain a mixture of different size particles, so it often feels lumpy. Loam soils are usually the best for farming because they are usually very rich in nutrients. Discover Science: “Rusting” Georgia Soil You have read that soils form from the weathering of parent rocks and minerals. Both physical and chemical weathering play a role in the types of soil formed. Red soils in Georgia result from the effect of a warm, humid climate weathering acid crystalline rocks on rolling hills over a long period of time. Much of Georgia’s soil is formed from granite and gneiss, which have a high acidity level. The presence of iron oxides mixed with the humid climate creates a chemical reaction causing the rocks to rust as they break down into smaller and smaller particles. This is what creates the red Georgia clay the state is known for.

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Because of the warm and humid climate of Georgia, many rocks that were originally black, white, and grey have been chemically weathered to red soil.

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STEMscopedia: SOIL COMPOSITION What Do You Know? The table below describes the properties of different types of soil. Use what you know about soil components to fill in the missing parts. In the first column, describe the size of each type of soil particle. In the second column, describe how each type of soil feels. In the third column, describe the color of each type of soil. In the fourth column, describe how well each type of soil retains water.

Size of Particles

Texture

Color

Does It Retain Water Well?

Loam

Sand

Silt

Clay

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STEMscopedia: SOIL COMPOSITION Connecting With Your Child Importance of Soil Quality in Agriculture Most students are familiar with dirt from an early age. However, they may or may not realize that soil quality and composition is important for determining how well the soil supports plant growth. Take a trip with your child to the local home improvement store or plant nursery. Locate a bag of gardening soil with a label that lists the soil characteristics. Some of these characteristics could be nitrogen content, organic content, etc. Use the soil content as a basis for discussing with your child the relationship between soil composition and soil function. For example: • What are the properties of the soil? Is it light or dark in color? Is the texture rough and dry, or wet and smooth? (Gardening soil is typically dark and damp.) • What components are in the soil? (Common answers include nitrogen, carbon, and phosphorous.) • If the soil manufacturer had not added these things to the soil, how else could these materials be added to soil? (One method is to compost organic material, and then add the results to soil.) At home, collect a small sample of soil from your yard or a green space near you. Examine the properties of the soil and discuss common plants that grow in your area. Research the composition of soil near you and compare it to the soils you saw at the store. Some questions to ask: • Are there any commonalities? What are some of the differences? • Just by observing properties, can you determine some of the rocks that may make up your soil?

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6E5H Soil Composition

Reading Science Name:

Date:

Group:

On the Job With Dad 1

My father works as a landscape designer. He helps people choose plants and decorations for their yards and gardens. He finds plants that will grow well in that area, and in the sun or the shade.

I help my father at work. It’s fun being outside. I dig the holes for the new plants, and he pays me $10 at the end of the day.

Last weekend, we went to the soil supply store. It was my first time visiting. There were at least two dozen huge mounds of soil. Each of the soils are different and each comes from a different location. The soil is bulldozed out of the ground at its source and transported to the soil supply store in a dump truck. Landscape designers and gardeners and construction teams go to the store to buy the type of soil that is needed.

Some of the mounds of soil were gray or brown. Others were red or had a green tint. Some were mostly gravel, while others were mostly clay or sand.

“I don’t understand,” I said to my Dad. “Why do we need to have so many different types of soil? Isn’t it all just dirt?”

My father smiled and said, “You might think so, but each type of soil is different because of where it was formed. Remember when you were flying to see your Aunt Jane in Atlanta? You looked out of the airplane window and said the earth looked red. That is because the soil in Atlanta has a lot of clay in it.”

Dad pointed to a mound of soil that was dark brown, almost black. “Do you see that very dark soil? That comes from an area where many plants have grown, died, and decomposed. It has many of the nutrients plants need to grow. This type of soil would be best for flower and vegetable gardens.”

“Some soil is light and sandy,” Dad continued. “I might use sandy soil under playground equipment. It helps cushion falls. I wouldn’t want a child to fall on hard-packed clay. I might also use sandy soil for customers who want their yards to have a desert feel. I have to find the right soil for each job.”

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Reading Science Continued 9

“Why are all of the soils so different?” I asked. “My teacher said soil is mostly broken-down rock.”

My father answered, “That’s true, but not all rocks are the same. Rain and wind break down different types of rock to create the different types of soil. The black soil we saw on vacation in Hawaii was formed from black volcanic rocks. We don’t have that kind of soil here because there is not any volcanic rock.”

I might become a landscape designer like my father if I keep learning about soil, rocks, and landscapes.

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Reading Science 1.

What is the main idea of the passage? A

It is hard work to become a landscape designer.

There are many different types of soil.

It can be fun to go to work with a parent.

Soil is made from rock.

Which of these could be formed into a mound (paragraph 3)? A

Water

Eggs

Salt

Milk

Which type of soil should be used to grow flowers? A

Red clay soil

Dark brown soil

Sandy soil

Soil with pebbles

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Reading Science 4.

Which phrase would go in the empty box?

The rocks break down into small pieces which form soil.

The rocks stick together to form larger rocks.

The rain and the wind cannot affect the rocks.

Flowers grow out of the rocks.

What is something a student might be able to tell about soil from looking at it? A

How much it would cost

How much would be needed for a flower pot

How old it is

What type of rock it came from

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Math Connections Name:

Date:

Group:

The five factors that influence soil formation are: (1) parent material, (2) climate, (3) living organisms, (4) topography, and (5) time. Topography is the shape, slope, and length of slope that affect the rate at which water flow deposits or strips nutrients from the soil. The chart shows how land is classified based on the percentage of slope. Slope Type

% Slope

Parent Material

Nearly level

02%

Fine-loamy alluvium

Gently sloping

2–5%

Old alluvium

Moderately sloping

6–10%

Residuum weathered from igneous and metamorphic rock

Moderately steep

10–19%

Residuum weathered from mica schist

steep

20–25%

Residuum weathered from mica schist

Very steep

26+%

Residuum weathered from mica schist

http://www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/georgia/GA121/0/Fulton.pdf

Scientists have studied the soil in Georgia to help understand and maintain that soil. Observation Area 1 was located 200 feet east of Juniper Street in Mountain Park, Georgia. There are hills in the area. The flattest area they measured rose 20 feet for every 100 feet across. 1.

What is the rate of slope (rise/run)? Write it as a ratio in lowest terms.

Write this rate as a percent.

Based on the chart, how would the slope be classified?

From what parent material was the soil formed?

Observation Area 2 was located in the Lloyd-Gwinnett complex in Newton, Georgia. There are hills in the area. The flattest area they measured rose 6 feet for every 100 feet across. 5.

What is the rate of slope (rise/run)? Write it as a ratio in lowest terms.

Write this rate as a percent.

Based on the chart, how would the slope be classified?

From what parent material was the soil formed?

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6E5H Soil Composition

Writing Science Name:

Date:

Group:

LOOK

THINK Think about what soil is made of. WRITE Describe the main ingredients that make up Earth’s soil and explain how they got there. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E5H Soil Composition

Writing Science

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6th Grade Earth and Space Science

6E6A

Renewable and Nonrenewable Resources

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6E6A Renewable and Nonrenewable Resources

Student Journal Name:

Date:

Group:

Energy Sources Part I: So It’s Not Renewable? So What? 1.

What happened to the total amount of the resource?

How much was left for each successive generation?

Was anything left for a fourth generation?

If the pretzels represented all of the coal in the ground, what would have been the cause of the disappearance of the coal?

What would be the effect on the world’s energy stores?

Predict what would happen to the people who depend on coal for their energy source.

Did students who were part of the activity think about those who might come after them?

What connections do you see between what happened in the activity and what happens in the real world?

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6E6A Renewable and Nonrenewable Resources

Student Journal Part II: Present, Question, and Record Natural resource: ____________________________________ CIRCLE the side that you represent:

Advantages

Disadvantages

Resource Facts Data Table How is this natural resource formed?

Is this a renewable or nonrenewable resource? Explain what this means.

How is this natural resource used? What are the advantages of using this resource? (Include thoughts about availability, cost, pollution, and any other possible advantages.) What are the disadvantages of using this resource? (Include thoughts about availability, cost, pollution, and any other possible disadvantages.) If this resource is nonrenewable, what are some ways to conserve or alternatives to using this resource?

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6E6A Renewable and Nonrenewable Resources

Student Journal Part II: Question, Present, and Record, continued In the space below, record questions you might ask of the presenting groups. Each group will answer two to three different questions from the audience after they finish presenting. You do not need to write questions for the topic you researched.

Energy Resources Presentations Natural Resource

Questions I May Have

Coal

Oil

Natural Gas

Nuclear Power

Biomass

Wind

Hydropower

Geothermal

Solar

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6E6A Renewable and Nonrenewable Resources

Student Journal Part II: Present, Question, and Record, continued As each team presents, record key advantages and disadvantages in the chart below.

Energy Resource Data Chart Natural Resource

Advantages

Disadvantages

Coal

Oil

Natural Gas

Nuclear Power

Biomass

Wind

Hydropower

Geothermal

Solar

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6E6A Renewable and Nonrenewable Resources

Student Journal Reflections and Conclusions 1.

What makes an energy resource renewable or nonrenewable?

Why does society depend on nonrenewable resources? Justify your answer.

Why should society research and develop the use of renewable resources? Justify your answer.

What factors should be considered about energy resources when choosing to buy a new car or home? Explain.

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STEMscopedia: RENEWABLE AND NONRENEWABLE RESOURCES

6E6A

Reflect

You use Earth’s resources every day. When you eat cereal with milk for breakfast, you use resources from plants and animals. When you ride the bus to school, you use fuel resources. When you take a drink of lemonade or iced tea, you use water resources. A resource is anything on Earth that humans use. We can use some kinds of resources over and over. Other kinds of resources can run out. What are some examples of resources on Earth? What might happen if they run out? How can we keep them from running out? What are renewable resources and energy? Renewable resources can be replaced within a lifetime. Some renewable resources, such as plants and animals, provide food for humans. Other renewable resources, such as sunlight and wind, provide energy. What are some of our renewable resources? Solar/Sunlight: Sunlight is a renewable resource. The Sun will continue to shine for millions of years. We can use energy from the Sun in many important ways. Solar panels capture sunlight and turn it into electricity. Humans use this electricity to power homes and businesses. Wind/Air: Wind can be used to create electricity. Large windmills, called turbines, spin in fast-moving wind. The movement of the turbine’s blades creates electricity. Hydro/Water: Humans cannot survive without freshwater. The freshwater we use is replaced by the water cycle. Water is also a source of energy. Dams along rivers can use moving water to create electricity. The movement of water during tides can also provide energy. Biomass/Plants and Animals: Plants provide food, energy, and useful products for humans. For example, trees provide wood. Wood can be burned to heat a home. Wood can also be turned into paper or lumber. Plants like corn, strawberries, and carrots provide food for many animals, including humans. Animals such as fish and cows also provide food. Geothermal: This energy comes in the form of heat from Earth. It can come from hot rocks near Earth’s surface and go to extreme temperatures within Earth’s inner layers. Tidal: Tidal energy comes from turbines and special buoys that convert the ocean’s energy from tides to pollution-free electricity for humans. Wind blowing past these turbines (top) provides us with renewable energy. Carrots (bottom) are also examples of renewable resources. Every year, new carrots grow and humans use the carrots as a source of food.

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STEMscopedia: RENEWABLE AND NONRENEWABLE RESOURCES

What are nonrenewable resources? Nonrenewable resources cannot be replaced in a human lifetime. These resources take a very long time to form. When we use these resources too quickly, they can run out because there is not enough time to replace them. Four kinds of nonrenewable resources are nuclear (uranium), coal, oil, and natural gas. Coal, oil, and natural gases are called fossil fuels because they form from organisms that have died. Nuclear: The most common nonrenewable resource used in nuclear power plants is uranium. It is used to produced electricity and energy worldwide.

This machine, called a pump jack, pulls oil up from deep under Earth’s surface.

Coal: Coal is a solid material that takes hundreds of million of years to form. Coal comes from plants that died millions of years ago. Thick layers of rocks and soil covered the dead plants. The pressure of the rocks and soil turned the plants into a solid called coal. Humans dig coal out of the ground. Burning coal releases its energy. We can use this energy to produce electricity. Oil: Oil is a liquid fuel that also takes millions of years to form. Oil comes from tiny animals that died in the ocean millions of years ago. Layers of mud pressed down on the dead animals. The pressure from the mud turned the dead animals into a liquid called oil. Oil can be turned into gasoline and other kinds of fuels. Oil is also used to make products such as plastics, DVDs, and tires. Natural Gas: Natural gas forms the same way that oil does. Over millions of years, tiny dead animals are pressed down by mud and rocks. The pressure forms tiny bubbles of gas. Natural gas has no smell, but we can see it in its liquid form. It can be used to heat homes and cook food. How can we conserve nonrenewable and renewable resources? Nonrenewable resources cannot be replaced in your lifetime. If we use all the coal, oil, and natural gas on Earth, there will be none left. It will take millions of years to replace these resources. How can we conserve, or save, nonrenewable resources? One solution to this problem is to use less coal, oil, and natural gas. Because they are nonrenewable, we can’t replace or make more of them. Here are some ways we can use less nonrenewable resources. Use public transportation instead of riding in a car. Turn the lights off when you leave a room. Use fabric bags instead of plastic bags at the grocery store. Renewable resources also must be conserved. For example, trees can be used to make fuel, paper, and lumber. But what happens if you cut down all the trees in a forest? It might take many years for all of the trees to grow back. Humans should use some, but not all, of the renewable resources in an area. We should replace the resources we use as quickly as possible. For example, plant new trees to replace trees that are cut down.

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STEMscopedia: RENEWABLE AND NONRENEWABLE RESOURCES

What Do You Think? Look at the two photographs below. Are these examples of renewable or nonrenewable resources? Explain your answer.

Soil is a very important natural resource. Is soil a renewable resource or a nonrenewable resource? It’s both! Soil is nonrenewable because it is created from broken down rocks. Rocks take a very long time to be broken into small enough particles that they turn into soil. Also, when soil is used to grow plants like fruits and vegetables for many years, the nutrients in soil can be used up. This is why it can also be considered renewable. Compost can be made very quickly and added into the soil to enrich it. Because of soil’s importance, we must work to conserve soil just like any other resource. Humans can have a negative impact on all natural resources—soil included. Human activity can cause Earth’s surface to weather and erode. Humans can cause weathering and erosion by digging into the ground and moving rocks, sediments, and soil to other places during construction. The roots of trees and other plants help hold soil in place. When humans cut down trees, the soil loses its support and becomes more vulnerable to erosion.

compost: a mixture of decayed organic material used to fertilize and enrich soil erosion: the movement of sediments to another place

Pollution from cars, factories, and other human activities can also put more chemicals into the air and water. This makes it easier for chemical weathering to occur. For example, pollution can mix with water vapor in the atmosphere and fall as acid rain. Acid rain can easily dissolve limestone, as you can see in the photograph to the right. Humans can also have a positive impact on soil and Earth’s surface. By practicing soil conservation, humans can help reverse damage done to soils. Planting grasses and other plants are one of the best tools for soil conservation. The roots of plants help hold soil particles together and keep soil from washing away. Using a rain barrel is another way to practice soil conservation. Instead of washing away your yard, rain is collected in a barrel that you can then use to water your garden. Farmers can use many practices that will help conserve soil, such as terrace and contour farming.

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STEMscopedia: RENEWABLE AND NONRENEWABLE RESOURCES

Look Out! Some products, such as gasoline or plastics, are made in special factories. You might think these resources are human-made and do not come from Earth. But all resources can be traced back to some natural material that came from Earth. Gasoline and plastic are made from oil. Oil is a nonrenewable resource that comes from Earth. Looking to the Future: Overfishing Fish are an example of a renewable resource. Humans eat fish for food. The human population is very large. We have many people to feed. Better technology and bigger boats allow fishermen to catch more fish than we did hundreds of years ago. But we may be catching too many fish. Imagine that the ocean has 100 fish. What happens if we catch 90 of those fish? We will have lots of fish to eat. But only 10 fish are left to lay eggs and produce more fish. These 10 fish cannot lay enough eggs to replace all of the fish we caught. The fish population will start to decrease. This kind of fish might even go extinct. This is an example of overfishing. Overfishing happens when humans catch too many fish in an area. The fish population cannot survive. We have seen evidence of this in the North Atlantic Ocean. In the 1990s, humans caught too many cod. A cod is a type of fish in the Atlantic Ocean. The population of cod became so small that they almost went extinct. Scientists noticed the problem and stepped in. They recommended limits on the amount of cod that fishermen could catch. This allowed more adult cod to stay in the ocean and lay eggs. The population of cod began to grow again. Limiting the amount of fish that can be caught helps to keep fish populations healthy.

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STEMscopedia: RENEWABLE AND NONRENEWABLE RESOURCES

Connecting With Your Child Conducting a Survey People use resources from Earth every day. Nonrenewable and renewable resources provide you with the energy, food, and products you need to live. Work with your child to create a survey that asks the people around you how they use Earth’s resources. Here are some sample questions: • Describe how you heat your home. Do you use natural gas, oil, or another resource? • Where does the electricity in your home come from? Does it come from nuclear power, coal power, solar power, wind power, or another source? • Do you or your family members eat plant or animal products? • Are there any products in your home that come from nonrenewable or renewable resources? These products could include plastics, DVDs and CDs, computers, cellophane tape, air mattresses, baby oil, disposable diapers, latex gloves, petroleum jelly, firewood, paper, toothpaste, etc. • How do you or your family try to conserve resources? Try to construct questions that ask about both renewable and nonrenewable resources. Conduct the survey with your neighbors, family members, or your student’s classmates. After the survey is complete, review the results with your child, and make a poster or pamphlet that describes the results. Here are some questions to discuss with your child: 1. How are people using nonrenewable and renewable resources in their daily lives? 2. Which resources are used most often? 3. How are people conserving resources in their daily lives?

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6E6A Renewable and Nonrenewable Resources

Reading Science Name:

Date:

Group:

Wind Energy 1.

Have you ever been outside on a blustery day? The wind can blow hats off heads, golf balls off course, and kites through crazy paths in the sky. During intense storms such as hurricanes or tornadoes, winds can blow away cars and even houses. In short, wind is powerful. When harnessed, wind can supply a renewable energy source.

How can wind be utilized as an energy source? In order to maximize the potential of wind energy, scientists have developed wind turbines. Wind turbines are the opposite of fans. Fans use electricity to make wind. Wind turbines capture wind and convert it to electricity. A wind turbine is a machine in which blades attached to a rotor are turned by the wind. The blades turn a shaft, which is connected to a generator. The generator produces electricity. The turbine takes the wind’s kinetic energy and transforms it into electricity.

What are the advantages of using wind as an energy source? First, wind is plentiful. Second, wind is renewable. This means it will not be depleted as it is used. Wind is formed as a result of the Sun’s uneven heating of Earth. The Sun’s energy is not going to disappear for billions of years, so wind will continue to be an available resource. Third, wind energy is relatively affordable. Maintaining facilities that use the power of wind is less expensive than almost all other systems used for other energy resources—both renewable and nonrenewable. Fourth, wind is a clean source of fuel. Wind exists naturally and requires no burning (or polluting). Using wind as a source of energy is rated as having a “low” impact on the environment.

What are the disadvantages of using wind as an energy source? The most obvious disadvantage is that wind is unpredictable. It does not always blow where it will be harnessed. It does not necessarily blow when the demands for electricity are high. Wind farms are areas where wind turbines are stationed to receive wind energy. Building a wind farm is more expensive than building a traditional power plant that uses fossil fuels to produce electricity. The building of wind turbines has an initial cost in terms of money, energy, resources, and pollution.

California is a trailblazer in regards to using wind energy, producing more electricity from wind energy than any other state. To overcome some of the challenges of wind’s unpredictability, California ordered scientific studies to determine where to put wind farms. Surprisingly, winds of 8 to 55 miles per hour are ideal for producing electricity. Many locations around the country, both on land and in water, are suitable.

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6E6A Renewable and Nonrenewable Resources

Reading Science 6.

In 2010, only 11 percent of the energy sources for generating electricity in the United States were renewable energy sources, including wind, solar, hydroelectric, geothermal, and biomass energy. However, wind energy is currently the fastest growing method of creating electricity. There is good reason for that. Earth has always had wind as a resource. Now people have the knowledge and technology to effectively use that resource.

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6E6A Renewable and Nonrenewable Resources

Reading Science 1.

Why might wind farms be less expensive to maintain than traditional fossil fuel power plants? A

You don’t have to buy a supply of wind.

Fossil fuels are inexpensive.

It is more expensive to build wind farms.

Wind farms might not produce much electricity if it is not windy.

Which of the following is NOT a benefit of using wind as an energy source? A

Wind is a clean source of energy.

Wind is unpredictable.

Wind is a renewable source of energy.

Wind is inexpensive.

The primary function of a wind turbine is to ___________. A

produce wind from electricity

measure wind speeds

shut down when winds reach speeds of 56 miles per hour

produce electricity from wind

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6E6A Renewable and Nonrenewable Resources

Reading Science 4.

What does the word trailblazer in paragraph 5 most likely mean? A

Someone who uses fire

Maker of nature trails

Pioneer

Companion

Which of the following is a similarity between solar energy and wind energy? A

Both are nonrenewable energy sources.

Both are highly utilized energy sources.

Both are renewable energy sources.

Both are classified as highly pollutant energy sources.

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6E6A Renewable and Nonrenewable Resources

Math Connections Name:

Date:

Group:

Since 1980, the number of pounds (lb) of red meat and poultry eaten per year per person has increased from 168.2 lb to 175.7 lb in 2009. What is the average increase per year of the number of pounds eaten per person? (Round to the nearest hundredth.)

Write an equation and then solve for y, where y is the yearly per capita consumption of red meat and poultry, and x is the number of years since 1980.

How many pounds can be predicted to be consumed yearly, per capita, in 2016?

If there are 3,025 people in a local city, how much red meat and poultry will be consumed in 2016?

In 2000, the per capita consumption of wheat was 146.3 lb, but in 2005, it dropped to a record low of 133.2 lb annually. What is the average decrease per year of the number of pounds of wheat consumed per person?

Write an equation to solve for the number of pounds consumed per capita, y, given x, the number of years since 2000.

If this pattern were to continue indefinitely (which is unlikely), how long would it take for the number of pounds of wheat consumed per capita to reach 100? Round years to the nearest hundredth.

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6E6A Renewable and Nonrenewable Resources

Math Connections Use the table below for questions 8-13. (Ratios are written as X:Y. Be sure to get rid of common factors such that the format of your ratio is 1:X.) 2006 Energy Consumption in Petawatt Hours (pWH)

Fuel Type

2006 US Consumption in pWH

2006 World Consumption in pWH

Oil

11.71

53.33

Gas

6.50

35.65

Coal

6.60

38.38

Hydroelectric

0.84

8.71

Nuclear

2.41

10.14

Other

0.95

1.38

TOTAL

29.26

148.41

8. What is the ratio of US consumption to world consumption of oil? Round to nearest tenth. 9. What is the ratio of US consumption to world consumption of nuclear fuel? Round to nearest tenth. 10. What is the ratio of US consumption vs. world consumption of fuel? Round to nearest tenth. 11. Describe the overall relationship between the US consumption and the world consumption. 12. Round the total US consumption and the world consumption totals to the nearest whole number in order to simplify the ratio of US consumption total to world consumption totals.

13. Considering that the world population is 7 billion and the US population is 300 million, compare the ratio of the populations to the ratio of total energy consumption by each population (per capita and round to the nearest whole number for any calculations).

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6E6C Rising Global Temperatures

Math Connections Name:

Date:

Group:

Greenhouse gases help to keep Earth warm enough for life to exist. However, elevated levels of greenhouse gases may cause Earth to become too warm. The majority of the scientific community has agreed that human activity is having a negative effect on global climate through the production of greenhouse gases, mainly carbon dioxide, or CO2.

Use the graph above to answer questions 1–2. 1.

Write a fraction to represent the part of the pie graph that is made up of CFCs and nitrous oxide combined.

What is the ratio of CFCs to carbon dioxide in the chart?

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6E6C Rising Global Temperatures

Math Connections Use the table below to answer questions 3–9. CO2 Emissions Added to the Atmosphere by Vehicles Vehicle MPG Pounds (lbs) CO2 Per Gallon Compact Car 24 20 Full-size Car 16 20 Truck/Van 13 21 Bus 8 22 3.

Ms. Feliciano’s class has 6 students that ride a bus to school. The average distance from their bus stop to the school is 24 miles. How many pounds of CO2 did the bus release picking up her students in the morning?

All of Mr. Bryan’s 21 students live in a new development outside of town. It is 16 miles from the development to the school. 4.

If two-thirds of his students ride the bus and the remaining arrive in their individual parent’s fullsized cars, how many students ride the bus to school?

How many students arrive in their parents’ cars?

How many pounds of CO2 total were released into the atmosphere from his students arriving at school? Complete the equation by adding units and numbers, and then solve.

1 bus x (16 miles / _______mpg) _______ lbs CO2+ (7 cars x _______ lbs CO2) = ______ lbs CO2

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6E6C Rising Global Temperatures

Math Connections Use the table from the previous page to answer questions 7–9. 7.

Becca’s family traveled 572 miles from Omaha, NE to Little Rock, AR to visit her grandmother. If they took their truck, how much CO2 did their vehicle release into the atmosphere traveling to her grandmother’s house? Write an equation and solve.

Becca’s cousins traveled from Amarillo, TX to Little Rock (598 miles) in their full-size car for the same trip. How much CO2 did they release driving to their grandmother’s house? Write an equation and solve.

Alter your equation from the question 7 to represent the same trip, but in a compact car. Write your new equation and solve.

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6E6A Renewable and Nonrenewable Resources

Writing Science Name:

Date:

Group:

LOOK

THINK Baking requires heat energy. Without the addition of heat, the physical properties of the ingredients would not change to resemble a muffin. Think about the renewable and nonrenewable energy resources related to the production of heat. WRITE Explain and compare each type of renewable and nonrenewable resource that could be used to produce heat energy for the purpose of baking muffins. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E6A Renewable and Nonrenewable Resources

Writing Science

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6th Grade Earth and Space Science

6E6B

Sustaining Natural Resources

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STEMscopedia: SUSTAINING NATURAL RESOURCES 6E6B

Reflect Think about the natural resources you have already used today. You used water to brush your teeth and shower. You most likely used fossil fuels when you took the bus or drove to school. And you are probably currently writing with a wooden pencil that has a graphite lead. Humans rely on natural resources every day. Do you think we are responsible for our management of these natural resources? The Price of Progress Human societies are supported by the natural resources and biodiversity of Earth’s systems (geosphere, hydrosphere, atmosphere, and biosphere). As societies have grown and advanced, Earth’s natural resources have been depleted at an alarmingly fast rate. Fossil fuels and coal have been pulled from the ground to support the energy needs of growing communities. Land has been cleared to develop cities, and the lumber has been hauled off to become building supplies elsewhere. With all this human interference, it should be no surprise that Earth’s systems are impacted. This includes affecting ecosystem biodiversity. How do you think biodiversity might be affected by the activities below?

biodiversity: the amount and variety of species in an area or ecosystem

Responsible Management In order for people to sustain the quality of living that they are accustomed to, they need to responsibly manage the usage and treatment of natural resources. Think back to how much water you personally use on a daily basis. Now multiply that by every person in the world. To help prevent the overuse of natural resources like water, policies have been established to manage it. Some cities regulate when and how often grass can be watered. Other communities recycle runoff water and use it to irrigate other areas without having to use drinkable freshwater.

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STEMscopedia: SUSTAINING NATURAL RESOURCES

Protecting the Environment Humans are impacted by the environment around them. Therefore, human health is dependent on monitoring the environment carefully. Unfortunately, human activity can contaminate the environment. Some examples of how humans negatively affect the lithosphere include improper disposal of industrial waste, use of fertilizers, and excess human waste. The environment may contain dangerous levels of substances that are harmful to human beings. That’s why it’s important to monitor the soil, air, and water, and take steps to make these factors safe for all organisms. The good health of humans requires monitoring the environment, maintaining soil quality, and stewardship. Stewardship is the management or care of Earth’s environment and resources. Farming techniques, like crop rotation, help maintain soil quality. Soil provides plants with nutrients that we consume when we eat them. If soil quality is not monitored or the soil becomes contaminated, the whole ecosystem is negatively impacted. Who wants to eat contaminated fruits and vegetables?

What Do You Think? Sustainability of Societies Water is not the only natural resource that needs to be responsibly managed. For example, modern societies require electricity to function— lots of electricity. How do the electrical companies find the energy to supply this electricity? They find it predominantly through natural resources like fossil fuels or coal. These nonrenewable resources cannot be the sole answer to the world’s energy needs because, as the term indicates, once nonrenewable resources are used up, they are gone forever. Therefore, in order to sustainably meet the energy needs of society, people have begun to invest time and money into developing alternative energy resources. The picture to the right shows two of these alternative energy options (solar and wind).

Try Now What do you know? As human populations and per-capita consumption of natural resources continue to increase, so might the negative impacts of this consumption on Earth. Scientists and engineers are constantly trying to develop new technologies and ways to conserve natural resources while meeting the demands of growing human populations.

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STEMscopedia: SUSTAINING NATURAL RESOURCES

Using the space below, brainstorm activities and technologies you can do or use to help conserve the world’s natural resources. Conservation Activities

Conservation Technologies

Connecting With Your Child Exploring Water Conservation at Home To help your child learn more about the importance of protecting watersheds, each member of your family can document his or her water usage. First, discuss with your child where your family’s water supply comes from. Do you have a well in your backyard or does your water come from human-made reservoirs? Is your water treated or filtered before it flows through your pipes? Do you generally drink from the tap or do you buy bottled water? Then have each family member keep a log of all the water he or she uses in a day. Note every time you do these activities: • Wash your hands • Take a shower or bath • Do laundry • Flush a toilet • Drink a glass of water • Brush your teeth • Use water in some other way

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STEMscopedia: SUSTAINING NATURAL RESOURCES

When documenting your water usage, include details such as: • Did you turn the faucet on to full blast, a slight trickle, or somewhere in between? • Did you drink the whole glass of water or did you pour some of it down the drain? • How long were you in the shower? • How full was the bathtub? • Did you leave the water running while you brushed your teeth, or did you turn it off while you were not using it? After 24 hours, compare each person’s water usage logs. Then have a family discussion about how much water you collectively use. Try to determine some ways for your family to cut back on your water usage, and discuss why this is important. Here are some questions to discuss with your family: 1. How much water do we use every day without really thinking about it? 2. How much water are we actually using and how much are we wasting? 3. How can we waste less water? 4. Why is it important to conserve water?

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6E6B Sustaining Natural Resources

Reading Science Name:

Date:

Group:

Molarity, Mercury, and You 1.

Water quality is a huge issue for modern society. Concerns over water quality are growing every day. As towns and cities expand, the demand for power from coal-burning plants increases. This raises increasing concerns about how to monitor our water quality. Both scientists and city health managers need to monitor more than just the water that we drink. This is also an issue to the freshwater and ocean water supplies and the organisms that live in them. The first step is to be able to measure the amount of compounds or elements that may be found in water. We also need to understand what levels are healthy. One specific element that has recently made headlines regarding water quality is mercury.

Coal-burning plants are one way that mercury finds its way into our water systems. As the coal is burned, winds carry the byproduct to nearby waterways. Tons of elemental mercury are released each year. This element interacts with certain microorganisms within the soil or in deep ocean sediments. It can undergo a chemical reaction that produces the highly toxic compound [CH3Hg]+, commonly known as methylmercury. Let us use this as an example to show the importance of understanding the concentration of solutes within solutions.

The quantity of particles present in the water supply is measured in concentration units. Concentration is a measurement of the amount of solute that is dissolved in a given quantity of solvent. You may already be familiar with a concentration unit called parts per million, or ppm. This unit tells you how many particles of a solute there are for each million particles of solution. However, this unit is usually used for very small concentrations of solutes. This unit can be converted to molarity, a concentration unit used more widely in chemistry. Molarity measures the concentration of solute in a solution. Molarity is expressed as the number of moles of solute dissolved in 1 liter of solution, by the equation mol/L, and the unit M.

Concentration is a type of empirical evidence. This means that it is a property that can be directly measured by a laboratory procedure. These measurements are repeatable—they can be made in different labs by different researchers. Direct observations are also considered empirical evidence.

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Reading Science 5.

Why is this important with respect to methylmercury? Small fish and other water animals can absorb small amounts of the mercury that enters waterways. These smaller animals are then eaten by larger fish, such as salmon. As the salmon eat the smaller animals, the mercury from the prey stays in the predators’ bodies. Much larger amounts of mercury can accumulate in their systems. This is also true of other fish-eating predators, such as otters, pelicans, and eagles. Scientists call this bioaccumulation. According to the Environmental Protection Agency (EPA), methylmercury can be hazardous to wildlife as well as humans. In birds and fish, high levels can cause difficulty in reproducing. It also hurts the growth and development of the young.

People also eat fish, including many predators that can have higher levels of methylmercury. These include salmon, swordfish, and some species of tuna. Health effects can include heart problems, weakened immune system, and nervous system disruptions. In order to protect people, we must understand the levels of mercury that are safe for human consumption. The EPA has determined that levels of mercury in fish as high as 1.0 ppm are safe to eat. So how do parts per million relate to the molarity of solutions? Look at the following formulas: ppm = mass solute (g) / (mass solvent + solute (g)) which is equivalent to mass solute (mg)/volume solution (L) when the solvent is water Molarity = moles solute (mol) / volume solution (L)

Therefore, if you know the molar mass of the solute in solution, you can find the molarity of the solution from the ppm. Methylmercury has a molar mass of 215.61 g/mol. Therefore, using mg/L, we can convert 1 ppm of methylmercury to molarity of methylmercury in this way: 1mg (CH3Hg)+/1 L solution x 1 g/1000 mg x 1 mol/215.61 g = 0.0000046 mol/L or 4.6 x 10-6 M

Therefore, the safe concentration of methylmercury in fish for people to eat is 4.6 x 10-6 M. From this answer, you can see that this concentration in molarity is very small. Expressing it in ppm makes it easier to visualize.

Scientists are making surveys of methylmercury concentration all over the world. This is an issue of global concern. Scientific studies of the concentration of mercury in ocean fish brought 147 countries together in January 2013. An international treaty detailing methods of reducing mercury emissions into the environment was signed. This is sure to benefit people and wildlife all around the world. Concentration surveys provide another benefit. Areas that are more highly contaminated can be identified for more aggressive cleaning and remediation. For example, methylmercury concentrations can be much higher in some estuaries. The river concentrates the pollutant in the silt.

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Reading Science 1.

The passage discusses some of the concerns with water quality and the concentrations of solutes within our water. Why is it important to monitor the concentration of solutes in our water? A

It affects the water we drink.

It affects the organisms in the water.

It affects the organisms we eat.

All of the above.

Which of the following statements gives empirical evidence that could be used to support the concept of bioaccumulation? A

The FDA recommends that young children eat no more than two fish meals a week and do not eat shark to protect them from mercury.

A factory dumped waste containing mercury into Minamata Bay in Japan. In the 1950s and 1960s, many residents suffered from severe mercury poisoning.

Predatory fish have higher methylmercury concentrations than other fish. Apex predators of fish have the highest concentrations.

Clams are filter feeders living in the silt. In contaminated areas, they have very high concentrations of methylmercury in their flesh.

Which unit of concentration is equivalent to mg/L? A

ppm

Molarity

Molar mass

Normality

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Reading Science 4.

One particular unit of concentration is used for solution concentrations that can easily be measured and weighed. Which unit would be most appropriate to use for average solution concentrations? A

ppm

Molarity

Molar mass

Normality

A scientific study found that the safe level for chlorine in drinking water is 4 ppm. Using the conversions shown in the reading, convert the ppm unit to a molarity unit. How many moles of chlorine per liter of drinking water are safe for human consumption? Use the space provided below to show all of your work. A

1.13 x 10-4 M

4.33 x 10-3 M

0.113 M

1.22 M

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6E6B Sustaining Natural Resources

Math Connections Name:

Date:

Group:

Prior to 2006, the Ipswich watershed, located north of Boston, Massachusetts, experienced extremely low flows into the Ipswich River. The low flows occurred mainly during the summer months due to an increase of public water use. Concerned about the lack of water, the USEPA (US Environmental Protection Agency) designed a study to test the effects of installing weather-sensitive irrigation controller switches (WSICS) at residences and athletic fields. These switches are fitted with a rain gauge and receive regional weather data from satellites. When the readings indicate that the soil moisture is low, they trigger an irrigation cycle. A box-and-whisker plot is a graphical display of the data, which splits the data into “quarters.” The circle on the graph represents the mean of the data.

The data are presented below as a box-and-whisker plot to show the water usage before and after the installation of WSICS in nine households. The control group represents 71 households. Water Usage Before and After WSICS Installation

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Math Connections Use the graph on page 1 to answer the following questions. 1.

Fill in the approximate median and mean for each group in the chart below. Control Group Before After

Experimental Group Before After

Mean Median 2.

How did the installation of the WSICS affect the water usage of the experimental households?

Was there any significant change in the water usage of the control households?

How did the range of data change among the experimental households before and after the installation of the WSICS?

How did the spread of the data change among the experimental households before and after the installation of the WSICS?

Using the data from the households, scientists were able to make predictions about the effects WSICS could have on the water usage of local athletic fields. The graph below shows the actual water use compared to the predicted water use if the fields install WSICS.

hich school shows the greatest W percent decrease in water usage?

hich school shows the least percent W decrease in water usage?

Based on the data, would you recommend the installation of WISCS in your community? Why?

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Writing Science Name:

Date:

Group:

LOOK

THINK There are many solutions for sustaining our natural resources of soil, water, and air. Think about how to avoid contamination and overuse of soil. WRITE Crop rotation is one strategy for protecting nutrients in soil. Evaluate this strategy and design your own solution for sustaining and protecting the quality of soil as a natural resource. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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Writing Science

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6th Grade Earth and Space Science

6E6C

Rising Global Temperatures

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6E6C Rising Global Temperatures

Student Journal Name:

Date:

Group:

Putting Together a Temperature Puzzle PBL Entry Document Your state has experienced extreme weather pattern events in recent years. During the summer season, it has either been extremely hot and dry or extremely hot and humid. It seems as though every summer is hotter than the last. These divergent weather patterns can be quite unsettling. Extreme weather can cause damage, endanger lives, and disrupt the livelihoods of many people in our community. For those whose livelihood depends upon predictable seasons, such unpredictability and lack of rainfall can translate into abrupt falls in revenue. This provides an early economic indicator of what climate change looks like. Your local communications and marketing department is looking for possible causes or reasons as to why summer season conditions may have changed and possible solutions that can help people prepare for unpredictable occurrences in weather. The department is reaching out to the community through a campaign called “Call to Action” to raise awareness of the potential impact of human activities and the phenomena of global warming. Your team’s mission is to create a product that will communicate the efforts of the “Call to Action” campaign. The purpose of the campaign is to generate a sense of urgency for action by raising the level of awareness about how human activities and natural Earth processes may contribute to global warming. Your product must communicate possible solutions to reduce one or more major factors that contribute to global warming and how models/technology can help us in making decisions about the effects of human activities that contribute to global warming. Your product must include scientific evidence in the form of maps, graphs, and charts to support your findings to questions you raise during your research and investigations. You will present your product to the communications and marketing department, who will carefully analyze the communication efforts of your product and proposed solutions. The product that most effectively communicates the “Call to Action” campaign purpose will be featured in a commercial ad for the campaign during prime time television hours. Each team will have three minutes to present their work. Divide your team into the following roles to complete the project: communications manager, environmental scientist, regional specialist, and graphic artist. Develop a list of what you already know and sketch several possible ideas. © Accelerate Learning Inc. - All Rights Reserved

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Student Journal Putting Together a Temperature Puzzle PBL Expert Roles Communications Manager and Team Leader The communications manager is the team leader. It is important for you to be mindful of the constraints as well as keeping your team on track to meet the criteria for a completed product. Your role is to keep the group’s work focused on the purpose of the project. Rubrics will help you keep your team on target with the many tasks that will need to be accomplished in a short time. Keep in mind the 21st century skill of communication that will be evaluated specifically. Environmental Scientist As the environmental scientist, your role is to ensure your team identifies one or more major factors in relation to human activities and the environment on a global scale. Your team product will need to reflect your reasoning for how the evidence supports the decisions of solutions your team will propose in the presentation. Regional Specialist As the regional specialist, your role is to ensure your team correlates the information presented by the environmental scientist to your specific region of the world. Your team product will need to communicate your reasoning for how the evidence supports the decisions of solutions your team will propose in the presentation. Graphic Artist As the graphic artist, your role is to ensure all the necessary maps, charts, and graphs are created for your product. You will need to work closely with the environmental scientist and the regional specialist to assure that all of their information is correctly presented in your created images.

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STEMscopedia: RISING GLOBAL

TEMPERATURES

Reflect

6E6C

Polar bears are the largest carnivores on land. They live in the Arctic, where they spend a lot of time on ice in the Arctic Ocean feeding primarily on seals. They are covered with thick fur, can grow up to 9 feet tall, and can weigh up to 1,500 lbs. These beautiful, fierce creatures are listed as “threatened” under the Endangered Species Act, which means they are in danger of becoming extinct. Why? Global warming is melting the ice in the Arctic Ocean where polar bears live and hunt for food. With the decreasing ice in their habitats, polar bears have to swim further and further to hunt for food, and swimming has become more dangerous. Scientists predict that two-thirds of the polar bear population will disappear in the next 40 years. Global warming is the rise in the average temperature of Earth’s surface. It is important to understand the difference between climate variability and global warming. Climate variability refers to how a climate fluctuates over a long term. Scientists study climate based on a 30-year range to avoid impacts from short-term differences. Climate change, on the other hand, is a long-term change of average weather conditions. Scientists have come to a consensus that our planet is getting warmer in a manner inconsistent with simple climate variability. Global warming is occurring, and human activities are major factors in the current rise in Earth’s average surface temperature.

• • •

How are humans contributing to global warming? How can humans lessen our impact on the environment and, thus, our contribution to global warming? How can we help reverse the damage we have already caused?

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Look Out Read through these five common misconceptions about global warming. 1. For millions of years, Earth has experienced climate change. The climate variation we are experiencing now is part of the natural cycle. Earth’s climate does have variations that are part of the natural cycle. The changes we are currently facing are not part of that cycle. Scientists studied many natural features (such as tree rings and ice cores) and discovered that both gradual and sudden changes have occurred throughout Earth’s history. However, those changes were caused by natural variations in the carbon cycle. Our planet is currently experiencing higher carbon dioxide levels than any in the last half billion years. Higher carbon dioxide levels in our atmosphere translate to higher temperatures. 2. Scientists are still debating whether humans are contributing to Earth’s climate change. Actually, there is a consensus among scientists that human activities are responsible for the rapid climb in Earth’s temperature. If we do not change our behavior, global warming will intensify, and the effects will become more hazardous. 3. Some places are becoming colder rather than warmer, so global warming is a falsehood. Evidence points to the fact that not all places on Earth are getting warmer. This is, in fact, true. Climate is affected by many factors. Depending on complex environmental factors, scientists predict global warming may create colder conditions for certain regions, such as northern Europe. Regardless, that does not change the trend that average global surface temperatures and ocean temperatures are on the rise. 4. Global warming doesn’t have to be a bad thing. Warmer winters will promote more plant growth, which is great for the planet. Although warmer winters in typically cold places might allow for increased plant growth in those areas, the benefits will be outweighed by many drawbacks around the planet. Disadvantages include: coral reefs dying and killing off vital food webs, ice caps melting and permanently flooding coastal cities worldwide, and droughts and flooding intensifying. 5. It is already too late for people to do anything about global warming. Inaction is the worst course people can take while facing this potentially devastating situation. Scientists have indicated that reducing our use of fossil fuels can have a positive impact on our environment and slow climate change. In addition, scientists are seeking methods to “recapture” carbon from the atmosphere and, hopefully, reduce the impact of climate change. However, to make significant progress, people have to work together at all levels—individually, industrially, governmentally, and internationally. 478

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Carbon Cycle Before you can understand the causes of global warming, it is vital to understand the carbon cycle. Carbon is an element present in the environment in a fixed amount. It travels throughout Earth’s systems through the carbon cycle. What is the carbon cycle? It is the process of cycling of carbon back and forth between living and nonliving components in the environment. Carbon is found in plants, animals, rocks, soil, and oil. Plants acquire carbon from the air through the process of photosynthesis. Animals gain carbon through the food chain. Animals exhale carbon back into the atmosphere. Not all carbon travels back and forth like this. Not all plants are eaten, so when they die, they decompose and carbon is both released into the atmosphere and stored in the soil. To simplify, the carbon cycle is when carbon transfers back and forth (at varying speeds) between carbon sources and carbon sinks. A carbon source is something that releases carbon, while a carbon sink is something that stores carbon. Earth’s lands, waters, and atmosphere continuously cycle the carbon.

What Do You Know? Carbon is found througout Earth. Earth’s system has many complex parts (atmosphere, biosphere, lithosphere, cryosphere, and hydrosphere) that require a delicate balance. If one part of the system changes, it can impact other parts, sometimes negatively. For example, forest fires caused by lightning strikes have happened throughout Earth’s history. They led to an increase in the amount of carbon dioxide in the air, but other Earth systems were able to adjust to this increase. Organisms in the biosphere, such as plants and plankton, can absorb some of this excess carbon dioxide and use it for photosynthesis, which releases oxygen into the atmosphere. This process can help return balance between the parts of Earth’s system. Carbon moves, or cycles, through Earth’s systems. Through the process of decay, carbon from plants and animals is returned to the soil. Carbon is also found in the hydrosphere as carbon dioxide dissolved in the water, in the marine animals and plants, and even in the shells and coral. Carbon can be found in the lithosphere and trapped in fossil fuels, such as coal, oil, or natural gas, or in rocks and volcanic material.

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Read the quick descriptions of each system, then label each system in the diagram. Finally, answer this question: “What effect would too much carbon have on each system?” atmosphere: the layer of gases that surround Earth biosphere: all of the ecosystems on Earth cryosphere: the frozen water on Earth hydrosphere: the system that includes all water on Earth lithosphere: the layer of Earth that includes Earth’s crust and a thin layer of the upper mantle Human Impact on Global Warming Although the carbon cycle is a natural process, human activities have changed Earth’s balance and how carbon moves through Earth’s systems. Deforestation Global deforestation causes two problems. First, deforestation by burning forests releases carbon dioxide into the atmosphere. Second, deforestation also eliminates a carbon sink by killing the plants that would absorb the carbon dioxide from the atmosphere for photosynthesis. Burning Fossil Fuels What exactly are fossil fuels? They are natural resources like coal, oil, and natural gas formed from the remains of animals and plants. We burn fossil fuels to run our cars, create electricity, and power our technology. Burning fossil fuels increases carbon in the air and causes numerous related problems. Smog is a combination of smoke and pollutants, which creates a haze in the air. It can irritate the lungs, eyes, throat, and nose. It is particularly dangerous for people with asthma. Smog is found near industrialized populations. Acid rain happens when chemical gases from burning fossil fuels mix with water in the atmosphere, making the water in clouds and precipitation acidic. Acid rain can kill trees, increase chemical weathering, and change the chemical balances in lakes and ponds, which can harm or kill the organisms in these ecosystems. Since wind can move clouds, gases, and particles in the air great distances, acid rain and pollution can be found far away from their sources. Open burning happens when smoke is released directly into the atmosphere without the use of the filter. Burning trash not only releases carbon dioxide but also puts other harmful gases into the air, such as nitrogen oxide and carbon monoxide.

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TEMPERATURES

Global Warming Solutions Since anthropogenic (caused or influenced by humans) activities have caused global warming and the problems associated with it, it is up to us to fix the problems and restore the balance. People have a duty to be good stewards of Earth. Reducing or reversing the impacts of human activities on the global climate requires creative solutions, and no single solution will fix the problems. Some solutions will help us reduce the amount of carbon dioxide being released into the atmosphere. For instance, reducing carbon dioxide emissions from burning fossil fuels will help. We can invent new technologies to burn fossil fuels cleanly. We can also use alternative energy sources so we do not rely on fossil fuels for all of our energy needs. Alternative energy sources include but are not limited to solar, wind, geothermal, hydroelectric, and biomass.

Besides just preventing climate change from becoming more severe, we have a responsibility to try to improve the current situation we have caused. Reducing the extent of climate change and human vulnerability to the impacts of climate change depends upon our knowledge and understanding of climate science, our engineering capabilities, and human behavior. We need wisdom to apply our knowledge effectively in our decisions and activities. Scientists are developing and testing several ideas to reduce the amount of carbon dioxide in the atmosphere. One simple answer is to plant a lot of trees, which will increase the size of the biosphere carbon sink.

What Do You Think? The Iron Hypothesis Scientists are always researching and searching for solutions to aid in the fight against global warming. The iron hypothesis was first proposed in the 1980s. It involves increasing photosynthesis in phytoplankton in global oceans. In addition to sunlight, carbon dioxide, and water, phytoplankton also need nutrients, like iron, for photosynthesis to occur. Scientists hypothesize that if we add iron to areas of the ocean where iron is limited, it will help increase photosynthesis. During photosynthesis, phytoplankton take carbon dioxide that has dissolved in ocean water and store the carbon in their biomass.

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The more carbon dioxide they remove from oceans, the more carbon dioxide from the atmosphere will dissolve into the ocean to replace it, thereby reducing the amount of carbon dioxide in the atmosphere. When the phytoplankton die, they will sink to the bottom of the ocean, storing the carbon there. There are still concepts scientists need to study, such as whether the phytoplankton’s biomass will truly sink to the bottom of the ocean and remain stored there without decaying. Additionally, they must investigate what effects could occur from adding large amounts of iron to parts of oceans. Earth is a system with many interacting components. Changing one aspect of a system can cause an impact elsewhere. 1. Do you think the iron hypothesis is a sound scientific idea? 2. What are some of the pros and cons that could occur if the iron hypothesis was adopted? 3. Should humans attempt to put it into practice? Why?

Connecting With Your Child Humans contribute to global warming on a daily basis. If every person in the world committed to changing a few detrimental habits, the impact on the environment would be immense. Make a pledge to become stewards of Earth. Guiding Questions: 1. How could you reduce the amount of pollution in your house? 2. Can you walk or ride a bike somewhere instead of driving? 3. Can you combine errands to reduce driving trips? 4. Can you reduce the amount of household trash you produce? 5. Can you recycle more? 6. Can you start composting instead of throwing away organic material? 7. Can you save electricity by turning off lights or technology? 8. Can you save natural gas by setting your thermostat differently? Brainstorm a list of ideas that your family will perform to become better stewards of Earth. Choose three tasks and commit to carrying them out for a month. Answer the following questions: 1. Do these tasks seem daunting or manageable? 2. Why do you think you have not attempted these environmentally friendly ideas in the past? 3. What do you think could happen if everyone in the world committed to performing three new habits that would help stop global warming?

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Reading Science Name:

Date:

Group:

Ice Cores and Observatories 1.

In comparison to the entire history of planet Earth, humans have only existed for a very short period of time. Yet human activities are having a huge effect on Earth’s systems. Before the Industrial Revolution, human activity affected the environments in which people lived. Farming and grazing practices changed ecosystems. Irrigation and damming practices affected waterways. Most of these changes only affected the small, or regional, areas where people lived. It has only been in the past 200 years that human activity has started to affect global systems. So what have these changes been?

The Industrial Revolution occurred in the mid-1700s to mid-1800s. Before this, human society was mainly a rural, agricultural society in which most of the work was done by hand with simple tools. There were no factories, no vehicles, and no sprawling urban areas. During the Industrial Revolution, everything changed. The discovery of fossil fuels as an energy source was the turning point. These fossil fuels include coal, oil, and natural gas. At that time, these types of fuels were inexpensive, easy to find, and easy to use. As a result, industry was able to grow in ways that it could not have before. The steam engine was invented. Large factories were built. People moved in large numbers into cities, so cities grew. Overall population grew as well. At the time, many of these changes benefited society in great ways. However, there was no way for the people of that time to know that the Industrial Revolution might affect global climates.

The climate changes of Earth’s past can all be attributed to a natural cause, generally an event that altered the amount of energy the planet received from the Sun. Since the Industrial Revolution, average global temperatures have steadily increased. We cannot associate this change in climate conditions with a natural event. This increase in average global temperatures is related to the steady increase in the amount of carbon dioxide (CO2) in our atmosphere. It has been the burning of fossil fuels that has led to an increase in the amount of CO2 found in the atmosphere. Thus, the Industrial Revolution is an important marker when it comes to an increase in global temperatures. This is also known as global warming.

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Reading Science 4.

Why is CO2 such an important factor when it comes to a rise in average global temperatures? CO2 is a colorless and odorless gas that has certain properties that allow it to trap heat. The CO2 in our atmosphere prevents some of the heat that radiates from Earth from going off into space. Therefore, CO2 is something called a greenhouse gas. This is not a bad thing in and of itself. We actually need CO2 in our atmosphere, and it has been in our atmosphere for a very long time. There are other greenhouse gases in our atmosphere in addition to CO2. Without them, all of the heat from the planet would be allowed to escape into space. In other words, our planet would be a virtual ice ball without CO2.

If we need CO2 in our atmosphere, why has it been a source of concern since the Industrial Revolution? As the fossil fuels, coal, and oil are burned, the carbon in them combines with the oxygen in the atmosphere and creates CO2. There is a branch of science known as climatology. Climatology scientists focus on studying Earth’s climates, both past and present. One of the ways that they are able to study past climates is by looking at something known as ice cores. Scientists drill into glaciers and pull out long cores of ice. There are some glaciers that have been around for hundreds of thousands of years. The farther down you go in the glacial ice, the older the ice is. Scientists can look at these ice cores, layer by layer, and find interesting data. They can look at the pollen that existed at different periods of time. More pollen points to warmer weather. They can also look at the gases trapped in the cores. These gases give the scientists a good idea of what gases existed in the atmosphere in the past. Then they measure the amounts of each gas found. They can determine the percentage of each type of gas that existed in the atmosphere. The data collected from the ice cores show an interesting trend. Average CO2 concentrations in the atmosphere were fairly stable for the 800,000 years before the Industrial Revolution. Concentrations shifted between 170 and 300 parts per million (ppm). Since the Industrial Revolution, CO2 concentrations have increased. Current atmospheric data shows CO2 concentrations close to 390 ppm.

Scientists also study what is currently occurring in the atmosphere. This data is very important. It shows how CO2 levels in the atmosphere are changing on a daily basis. This allows scientists to observe current trends and to hypothesize about possible explanations for increasing CO2 levels. Some of the most reliable measurements of current atmospheric CO2 levels are taken at the Mauna Loa Observatory in Hawaii. The current readings from Mauna Loa support the trend found in the ice cores samples. The Keeling curve is a graph that charts the changes in atmospheric CO2 concentrations based on these readings. The readings on the Keeling curve have steadily increased since 1958. Today’s readings are over 400 ppm.

We cannot say with absolute certainty that human use of fossil fuels is the main cause for global warming. In fact, there are other factors. Solar input and natural cycles of the orbit of the planet also affect overall global temperatures. However, scientific data shows that the rise in CO2 concentrations in the atmosphere relates to the increased burning of fossil fuels. CO2 is a greenhouse gas that traps heat. Therefore, there is concern that increased CO2 levels could result in an increase in global temperatures. However, there are many recent efforts to reduce the amounts of fossil fuels used. Energy efficient vehicles are becoming common. Renewable sources of energy, such as solar and wind, are replacing fossil fuels. These wise choices will help to reduce the impact that human activities have on the delicate systems of our Earth. © Accelerate Learning Inc. - All Rights Reserved 484

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Reading Science 1.

What change has occurred since the Industrial Revolution that has potentially caused a change in Earth’s average climate? A

An increase in population

Larger urban areas

The burning of fossil fuels

All of the above

Why are scientists so concerned about rising levels of CO2? What is it about this particular gas that makes it concerning? A

It produces a bad odor.

It can trap heat.

It has an unpleasant color.

It is only made by humans.

Which of the following statements about CO2 is not true? A

CO2 is just one type of greenhouse gas.

CO2 is harmful to the planet.

Life as we know it could not exist without CO2.

The CO2 in our atmosphere has been around a long time.

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Reading Science 4.

Why do climatologists study ice cores from ancient glaciers? A

To find out what the ancient glacier is made of

To find out how long humans have lived on Earth

To find out what was found in the ancient atmosphere

None of the above

The Mauna Loa Observatory in Hawaii has been taking atmospheric CO2 readings since 1958. What is the name of the graph that charts the changes in atmospheric CO2 concentrations based on these readings? A

The Mauna Loa trend

The Keeling curve

The CO2 trend

The Hawaiian Atmospheric Chart

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6E6C Rising Global Temperatures

Writing Science Name:

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LOOK

THINK Think about the factors that have contributed to the rise in global temperatures over the last century. WRITE Explain whether or not the picture above shows evidence that contributes to this temperature rise. Then identify human factors as well as natural processes that have led to the rise in global temperatures over the last century. Be sure to • clearly state your central idea; • organize your thoughts; • develop your essay in detail; • choose your words carefully; and • use correct spelling, capitalization, punctuation, and grammar.

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6E6C Rising Global Temperatures

Writing Science

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abyssal plain

GLOSSARY OF TERMS

abyssal plain – underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000m accumulation – a buildup or gathering of something that occurs over time air mass – bodies of air extending over large areas (1,000 milesor more) that develop and retain specific characteristics of pressure, temperature, and humidity

atmosphere

asteroid – large and small rocks or metallic masses orbiting the Sun; made up of materials similar to those that formed the planets asthenosphere – the solid layer with plasticity in the upper mantle that is located just below the lithosphere; lithospheric plates “float” and move on this layer astronomer – ascientist who studies objects in space, such as black holes, galaxies, moons, planets, stars, etc

air pressure – the force exerted by the atmosphere on Earth’s surface by the weight of astronomy – the study of celestial objects, space, and the air above the surface the universe as a whole air temperature – a atmosphere – the layer of measurement of the heat energy contained in the air in a gas surrounding planet Earth, held in place by gravity and certain location; helps predict composed of a limited number weather patterns of elements, primarily nitrogen and oxygen © Accelerate Learning Inc. - All Rights Reserved

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atmosphere

GLOSSARY OF TERMS

clay

atmosphere – a layer of gases biomass – material derived from living things surrounding Earth atmosphere – a layer of air surrounding Earth atmosphere – the layer of gas surrounding planet Earth, held in place by gravity and composed of primarily nitrogen and oxygen atmospheric movement – global air circulation patterns within the atmosphere held to Earth by gravity and warmed as heat radiates from Earth; influenced by convection of warm, less dense air (rises and spreads out) and cold dense air (sinks) big bang theory – a theory that says the universe began as a small point that expanded rapidly about 13.8 billion years ago

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carbon dating – the process of determining an approximate computed age based upon the proportions of carbon isotopes present characteristic – a feature that helps identify something chromosome – a single linear or circular piece of DNA that contains some or all of an organism’s genes classification – the grouping and characterization of things based on systematic examination and shared characteristics clay – a fine-grained soil that often contains organic material

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climate

GLOSSARY OF TERMS

climate – average weather conditions for a region year after year coal – a hard, black solid fuel formed from the remains of plants over millions of years and extracted from the ground; a nonrenewable fossil fuel

contribute

condensation – the change from gas state to liquid state conduction – the transfer of energy from one object to another through direct contact

conservation – efforts to wisely use, distribute, and protect valuable resources such as fresh water, soil, cold front – the border between an advancing cold air unique environments, and mass and a retreating warm air energy resources as well as natural and human-made mass materials comet – a celestial body of continental shelf – area ice, dust, and rock with an of seabed around a large elongated and elliptical orbit landmass where the sea is compaction – occurs when relatively shallow compared rock particles or sediments with the open ocean are pressed together or continental slope – the slope packed down by gravity and between the continental shelf the pressure of overlying rock and the ocean floor layers composition – the general makeup of something © Accelerate Learning Inc. - All Rights Reserved

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contribute – to help cause something to happen 495

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convection

GLOSSARY OF TERMS

density

convection – transfer of heat through the rising of hotter liquids and gasses and the falling of cooler liquids and gasses

core – the two-part layer of Earth below the mantle with a liquid outer core and a solid inner core, both a iron-nickel alloy

convection currents – a circular movement of fluids caused by the rising of hotter, less dense fluid and the falling of cooler, more dense fluid

crossing over – the exchange of genetic material between homologous chromosomes during meiosis; contributes to genetic variation

convection currents – a cyclical motion occurs because of density differences in the mantle. heated, less dense lower regions of the fluid mantle rise; denser, cooler regions sink due to gravity. the combined motions serve as the engine for crustal plate movement

decompose – to break down into simpler components or basic elements

convergent boundary – occurs when two tectonic plates move toward each other and collide

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deforestation – removal of a forest or stand of trees where the land is thereafter converted to a non-forest use delta – a triangular land form where a river empties into another body of water density – the amount of matter in a given space or volume; it is a relationship between mass and volume © Accelerate Learning Inc. - All Rights Reserved

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deposition

GLOSSARY OF TERMS

deposition – the process by which gravity, water, wind, and ice deposit weathered and relocated sediment diploid – the characteristic of having two copies of each chromosome

fossil fuels

erosion – the process by which water, ice, wind, and gravity remove and transport sediments from one place to another evaporation – the changing of water from liquid to a gas

divergent boundary – the boundary between two tectonic plates moving away from each other

fault – a crack in Earth’s crust resulting from the displacement of one side with respect to the other

earth’s tilt – a tilt in Earth’s rotational axis relative to its orbital plane

force – a push or pull that can change the motion of an object fossil – preserved parts or traces of animals and plants that lived in the past

earthquake – a sudden movement of Earth’s crust caused by the release of stress fossil fuels – preserved parts accumulated along geologic or traces of animals and plants faults or by volcanic activity that lived in the past emissions – the act of discharging energy, light, particles, and different types of waves © Accelerate Learning Inc. - All Rights Reserved

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fossil record

GLOSSARY OF TERMS

fossil record – the fossils and their locations in the sedimentary layers of Earth’s crust, which provide information about things that lived in the distant past fresh water – water found in rivers, lakes, glaciers, ice sheets, and underground that contains low concentrations of salt galaxy – a large grouping of stars, planets, gas, and dust in space held together by gravity

global warming

geocentric model – a model showing Earth located at the center of the universe geological record – the layers of rock, including its fossil content, that give information about Earth’s history geothermal power – heat transferred from beneath the surface of Earth and used to produce energy for human use glacier – a large, slow-moving, long-lasting accumulation of snow and ice that develops on land

gamete – cells that contain half the total number of chromosomes for an organism; global – affecting or relating to the whole world sex cells

genotype – the exact genetic information carried by a single individual

global warming – continuing rise in the average temperature of Earth’s climate system caused by an increase in the amount of carbon dioxide and methane in the atmosphere

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gas giants – outer planets made mostly of gases

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gravel

GLOSSARY OF TERMS

gravel – composed of rock fragments of various sizes gravitational pull – the attraction between two objects due to the invisible force of gravity; the gravitational pull from the moon is primarily responsible for the tides that form on Earth

heat and pressure

greenhouse gasses – gas in an atmosphere that absorbs and emits radiation within the thermal infrared range Gregor Mendel – an austrian monk and botanist who established key principles for the study of genetics; the father of genetics

gravity – the force of attraction that pulls objects toward each other; the force that controls the motion of our solar system

groundwater – water located below Earth’s surface; water that has seeped into Earth’s surface; stored in aquifers

greenhouse effect – the increase in temperature of the surface and lower atmosphere of Earth due to the trapping of heat by an accumulation of greenhouse gasses

haploid – a cell that contains a single set of chromosomes

greenhouse gases – gases in the atmosphere that trap heat within the atmosphere

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heat and pressure – changing variables due to the weight of overlying rocks, causing changes to rock characteristics and mineral composition, thus forming metamorphic rocks

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heliocentric model

GLOSSARY OF TERMS

heliocentric model – a model showing the Sun as a fixed point in the center of the universe with objects revolving around it high-pressure air mass – an air mass with greater atmospheric pressure than the surrounding air masses; air moves away from the center of the high pressure, traveling in a clockwise direction in the northern hemisphere and a counter-clockwise direction in the southern hemisphere humidity – amount of water vapor or moisture content in air hurricanes – a large, tropical weather system consisting of an extremely low pressure air mass with heavy rains and wind speeds of at least 119 km/h

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interaction

hydropower – a renewable source of energy based on the natural movement of water igneous rock – the rock formed when lava or magma cools and solidifies; lava cools quickly and forms rocks with small crystals, while magma cools more slowly and forms rocks with larger crystals inertia – an object’s tendency to resist changes in its motion infiltration – the process by which water passes through soil and seeps into the ground inner core – the sphere of solid nickel and iron at the center of Earth; surrounded by the liquid outer core interaction – action that occurs as two or more objects have an effect upon one another

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lake

GLOSSARY OF TERMS

lake – a large body of water surrounded by land latitude – geographic coodinate that specifies the north-south position of a point on Earth’s surface

mesoshpere

lunar eclipse – the full moon passes into Earth’s shadow causing the moon to appear reddish in color when the Sun, Earth, and Moon directly line up; lasts 1-3½ hours

mantle – the solid layer of lithosphere – the outermost Earth between the crust and part of Earth that comprises the the core; made of dense crust and the uppermost part of silicates the mantle mass – the amount of matter in low-pressure air mass – an something; measured in grams air mass with less atmospheric pressure than the surrounding meiosis – cell division that results in the production of air masses; air moves toward haploid gametes; sperm and the low pressure, traveling in a counterclockwise direction in egg the northern hemisphere and mesosphere – the third layer a clockwise direction in the of Earth’s atmosphere; located southern hemisphere between the stratosphere and thermosphere lunar cycle – the moon’s repeated pattern of changes in appearance due to its changing position relative to Earth and the sun as it circles Earth © Accelerate Learning Inc. - All Rights Reserved

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metamorohic rock

GLOSSARY OF TERMS

metamorphic rock– a rock that has changed in form due to high temperatures and pressure; the rock formed deep underground where heat and pressure cause existing rocks to be changed in both mineral composition and structural characteristics meteorite – remains of meteoroids that strike the surface of a planet or moon meteroid – a natural chunk of rock or dust existing outside of Earth’s atmosphere

motion

Milky Way Galaxy – the galaxy in which the Sun and Earth are located mineral composition – the unique combination of solid elements and compounds that make up a mineral minerals – a naturally occurring substance that is solid and stable at room temperature moon phase – what the moon looks like at different times of the month

moraine – a mass of rocks and sediments carried and mid-ocean ridge – underwater deposited by glaciers mountain range created when motion – describes change in magma rises between two an object’s position with respect tectonic plates at a divergent to time and in comparison to boundary other objects

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natural gas

GLOSSARY OF TERMS

natural gas – a gas usually found in the ground positioned above petroleum deposits and burned to obtain energy; a nonrenewable fossil fuel natural resource – recources that exsist in the environment without humane intervention nonrenewable – an energy resource that takes millions of years to form from the remains of plants and animals, such as coal,oil, and natural gas nuclear power – harnessing energy from the decay of uranium atoms ocean – a large body of salt water; cover most of Eath’s surface ocean waves – a disturbance in ocean water that transfers energy from point to point

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organic material

ocean currents – a directional movement of ocean water; surface currents result from steady winds over the ocean surface; deep currents result from density variations due to temperature and salinity differences oil/petroleum – a flammable yellow-to-black liquid composed of hydrocarbons occurring naturally beneath Earth’s surface; a nonrenewable fossil fuel processed to make gasoline used in vehicles orbit – the path one object takes as it revolves around another object in space organic material – material from the remains of dead organisms and their waste products in the environment

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organism

GLOSSARY OF TERMS

organism – a self-contained living thing that perform all of the functions of life outer core – the outer layer of Earth’s core; surrounds the inner core and is made of liquid, nickel, and iron

radar

planet – a celestial body that orbits the sun plasticity – a characteristic of the material in the asthenosphere; existing in a solid state yet having the ability to flow without being a liquid

ozone – gas in Earth’s atmosphere that absorbs most of the damaging high-energy ultraviolet radiation from the Sun

plate tectonics – theory that the lithosphere is divided into tectonic plates that slowly move on top of the asthenosphere

phenotype – the physical appearance of an organism

precipitation – rain, snow, sleet, or hail that falls from clouds in the sky

pollution – the presence of paleontologist – a person who harmful or unwanted levels of material in the environment studies fossils

physical weathering – geological process of rocks breaking apart without changing their chemical composition

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preserved – to be kept in its original state radar – system for bouncing electromagnetic waves off of objects to locate them; used to track weather patterns © Accelerate Learning Inc. - All Rights Reserved

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radiation

GLOSSARY OF TERMS

radiation – the transfer of energy through air or empty space

rotation

renewable – an energy resource such as trees or wind that is replaceable by natural means

rain guage – a tool that measures the amount of rainfall revolution – move in an elliptical path around a center recycling – properly disposing used resources so they can be rift valley – a trench formed reprocessed into new products between highlands on a divergent boundary where the regional – affecting a particular plates separate region river – a body of fresh water relative – in comparison to that flows continuously towards something else the ocean relative position – where an object is located in relation to another object renewable – a resource that cannot easily be exhausted because it is rapidly replaced by nature

rock cycle – Earth’s rocks change from one type into another over time due to various Earth processes. changes occur in mineral compositions and physical structures rotation – to spin on an axis; the spinning of Earth on its axis that causes day and night to occur

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runoff

GLOSSARY OF TERMS

solar power

sedimentary rock – the rocks formed when particles of other rocks are deposited in layers and are compacted (crushed together), and cemented salinity – saltiness or dissolved (binding of the sediments) salt content of a body of water soil – a mixture of minerals, salt water – water found in organic matter, gases, and oceans (and few lakes) that organisms that can support contains 3-4% salt plant life runoff – rainfall and surface water that drains or flows from the land into streams, rivers, lakes, or the ocean

satellite – something that orbits around another object, including a moon orbiting a planet, or a man-made object orbiting Earth

soil – a mixture of sand, silt, clay, rock and humus (plant and animal remains)

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solar eclipse – the moon passes between Earth and season – a part of the year that the Sun, covering all or part has a certain type of weather of the Sun; occurs when the Sun, Earth, and Moon directly sediment – Earth material that line up; lasts for less than 12 is broken down by processes minutes. of weathering; can be eroded and deposited by the agents of solar power – harnessing water, wind, ice, and gravity energy from the sun with the use of solar panels

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solar radiation

GLOSSARY OF TERMS

topsoil

thermal energy – energy that solar radiation – the electromagnetic energy emitted is measured by a thermometer from the Sun thermosphere – the fourth solar system – the Sun and all layer of Earth’s atmosphere; of the objects that move around located between the mesosphere and exosphere it stratosphere – the second layer of Earth’s atmosphere; located between the troposphere and mesosphere subduction – the process in which a denser plate is pushed downward beneath a less dense plate when plates converge; occurs at continental to oceanic boundaries and oceanic to oceanic boundaries surface winds – winds above Earth’s surface terrestrial planets – interior planets made mostly of rock; Earth-Like

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thunderstorm – a storm that is formed by the quick movement of warm, moist fronts into the cool atmosphere; also know as a lightning storm tidal – harnessing power from tides and converting it to power tides – the rise and fall of the level of the sea in response to the pull of the Moon’s gravity topography – a description of land surface area with reference to variation in elevation topsoil – the top 2 to 8 inches of soil

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tornado

GLOSSARY OF TERMS

tornado – a violently rotating column of air extending from a thunderstorm to the ground with wind speeds from 40 to 318 mph. transform boundaries – occurs when two tectonic plates slide past each other

waste

universe – all space and the matter space contains v-shaped valley – a valley formed into a V-shape by flowing water

variability – the measure of the tendency of single genotypes in a population to transpiration – the evaporation vary from one another of water through openings on volcano – a mountain or hill the leaves of plants made by hot rocks and gasses moving to the surface of Earth trench – deep and narrow from deep inside Earth depressions in the seafloor where the subducted plate moves into the asthenosphere warm front – the boundary between an advancing warm air mass and a receding cooler troposphere – the layer of atmosphere closest the surface air mass of the Earth; where weather waste – properly disposing occurs used resources so they can be reprocessed into new products u-shaped valley – a valley shaped like a U that is formed by glaciers moving along and down a slope 508

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water cycle

GLOSSARY OF TERMS

wind speed

water cycle – the change of water from one state to another as it moves between Earth’s surface and the atmosphere weather – the day-to-day state of the atmosphere weather map – a map or chart that shows the weather conditions at a specific point in time over a specific region weathering – the mechanical or chemical processes that break rocks into smaller pieces and sometimes change the chemical composition wind – a natural movement of air, sometimes with considerable force, from an area of high density and pressure to an area of low density and pressure wind speed – measured by anemometers; helps predict changes in weather patterns © Accelerate Learning Inc. - All Rights Reserved

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6 STEMscopes Georgia Student Notebook

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6th grade Notebook

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