Type:
Solution Manual
Resource:
Introducing Physical Geography
Edition:
6th Edition
Author(s):
Alan Strahler
Instructor’s Manual for Strahler, Introducing Physical Geography, 6th Edition Chapter 1: Earth as a Rotating Planet Chapter Objectives: Upon completion of this chapter the student will be able to: 1) Describe the shape of the Earth. 2) Explain Earth’s rotation. 3) Describe the features of the geographic grid. 4) Explain different types of map projections. 5) Describe Earth’s time zones. 6) Describe Earth’s seasons using its revolution around the Sun. This chapter introduces a few of the fundamental tools that geographers use including maps, GIS, and GPS. There are a number of ways that we can introduce these topics to appeal to the variety of interests and learning styles of your students. A Historical Perspective: For many non‐science students, topics in physical geography can seem distant and unfamiliar. The historical aspects of maps, and the ways in which we have developed these techniques over hundreds of years, provide a useful method to instill interest and enthusiasm in these students. The following list of internet resources furnishes students with interactive learning opportunities, creatively explaining each of the major topics presented.
Helpful Hints: • Following a review of seasons and daylight, assign students to follow the animations in WileyPLUS Follow up in WileyPLUS with a quick quiz. • Provide students with a list of world cities and, with the aid of an internet resource such as the WorldTime Interactive Atlas, have them calculate the different times in each of the cities when it is 9:00 am local time. • Similarly, provide students with a list of dates and assign them to look at the Guide to Arctic Sunrise and Sunset site to find out how many hours of daylight they would receive.
Relevant Internet Resources: ConceptCaching.com is a website that promotes student spatial awareness by relating specific features on Earth’s surface to their visual character and GPS coordinates. Photographs and GPS coordinates that demonstrate core concepts in geography are organized for viewing by core concept and by region. GeoDiscoveries animations and interactivities illustrate and reinforce key concepts. They are good for use in lectures and as demonstrations. Students can use the activities for practice or study. Nova Lost at Sea: The Search for Longitude. This web site, from the PBS series Nova, outlines the problems involved with developing an accurate system of longitude for navigation. http://www.pbs.org/wgbh/nova/longitude/ NOAA Digital Topographic Atlas provides many different topographic maps using digital elevation models. http://www.ngdc.noaa.gov/mgg/topo/topo.html This short webpage is a good introduction to Geographic Information Systems (GIS). http://www.gis.com/content/whatisgis WorldTime Interactive Atlas provides an interactive globe that allows you to point and click to find out the longitude, latitude and current time. http://www.worldtime.com/ World Time Server provides the current time and location of any country, including the different states of the US and provinces of Canada. http://www.worldtimeserver.com/ Guide to Arctic Sunrise and Sunset. This web site provides the hours of daylight and darkness for each day of the year for three latitudes in the Arctic region. http://www.athropolis.com/sun‐fr.htm SunAngle: Calculates solar angles and related information for a given location, date, and time. http://www.susdesign.com/sunangle/ SunPosition: Calculates the position of the sun and related information for a given location, date, and time. http://www.susdesign.com/sunposition/ Interactive World Time Zone Map provides a variety of ways to view the world’s different time zones. http://www.worldtimezone.com/
Tracking the North Magnetic Pole. It is important to remember that the geographic poles and the magnetic poles are different. This Canadian web site demonstrates how the magnetic north pole is moving. http://geomag.nrcan.gc.ca/mag_fld/magdec-eng.php Multimedia Tour of the Sun. This site from the Netherlands gives a clear and concise tour of the Sun and explains the processes and features of our nearest star. http://www.michielb.nl/sun/ Animation of the seasons. This web site shows Earth orbiting around the Sun and how the declination changes. It has a useful stop feature so you can pause to evaluate the seasonal changes. http://www.astro.uiuc.edu/projects/data/Seasons/seasons.html Tutorial on Global Positioning Systems (GPS) by Trimble, a leading manufacturer of GPS equipment. http://www.trimble.com/gps_tutorial/ Introduction to LiDAR (Light Detection and Ranging), a relatively new airborne mapping technique. http://www.csc.noaa.gov/digitalcoast/_/pdf/What_is_Lidar.pdf
Chapter Lecture 1.1 The Shape of Earth: The Earth is not a perfect sphere, as evidenced by the 26 mi (42 km) difference between the equatorial diameter of 7,926 mi (12,756 km) and the polar diameter of 7,900 mi (12,714 km). The reason for this difference, even if it is slight, is due to the centrifugal force exerted on the planet by the Earth’s rotation. Thus, the equatorial bulge and the polar flattening make the Earth’s shape an oblate ellipsoid rather than a sphere. Actually, an even better characterization of the Earth’s shape is the geoid, which reflects the unevenness of gravitation pull. 1.2 Earth’s Rotation: Earth rotates on an imaginary straight line through the poles and center. One complete rotation is referred to a solar day that is divided into 24 hours. This axial rotation provides a ready reference for establishing a geographic grid of latitude and longitude, in addition to the convenience of having the day divided in hours, minutes, and seconds. 1.2.1 Environmental Effects of Earth’s Rotation: These include the following factors that are of substantive importance to all life forms: sunlight, air temperature, humidity, and motion are all affected by this diurnal rhythm. The Coriolis effect is a rightward deflection of air and ocean currents in the northern hemisphere that is caused by Earth’s rotation and varies from zero at the Equator to a maximum at the poles. The deflection is leftward in the southern hemisphere. Ocean tides on Earth are caused by the gravitational attraction of the moon and the sun as the planet rotates on its axis. 1.3 The Geographic Grid: An orderly system of imaginary circles, called meridians and parallels, is used to locate any position on Earth. It is necessary to establish these circles in order to make maps. 1.3.1 Parallels and Meridians: Parallels (of latitude) are east‐west circles that are parallel to one another. The equator at 0º is the largest parallel. We can define as many parallels as we want. 1.3.2 Meridians (of longitude) are north‐south lines that extend from one pole to another. As with parallels, we can define as many as we want. 1.3.3 Great circles pass through the center of Earth. 1.3.4 Small circles pass through Earth but not through its center. Meridians are halves of great circles, while all parallels, with the exception of the equator, are small circles. 1.3.5 Latitude and longitude are used to pinpoint any location on Earth’s surface. Latitude is measured as so many degrees north or south of the equator to either pole, thus ranging from 0º to 90º. In comparable fashion, longitude is measured as so many degrees east or west of the prime meridian, the 0º reference point passing through Greenwich, England.