Issuu on Google+

Pascal Gunsch, Lotte van den heuvel, Maarten Hoogstad, Selina van luik, Ramona van Marion,


2012 The Science Gang, the Netherlands all rights inversed www.iceage.nl.ae Cover:

Pascal Gunsch

Graphic Designer:

Pascal Gunsch

Executive Editor:

Pascal Gunsch

Publishing Editor:

Selina van Luik

Website:

Pascal Gunsch

Texts:

p. 8-9 Pascal Gunsch p. 10-15 Selina van Luik p. 18-25 Pascal Gunsch p. 26-31 Selina van Luik p. 31 Ramona van Marion p. 32-36 Lotte van den Heuvel p. 36-38 Maarten Hoogstad p. 40-44 Pascal Gunsch p. 46-47 Ramona van Marion p. 50-55 Ramona van Marion p. 54-59 Maarten Hoogstad p. 60-65 Lotte van den Heuvel p. 53 Pascal Gunsch

Logbook: Figures:

Lotte van den Heuvel, Ramona van Marion Fig. 11.4 Maarten Hoogstad Fig. 12.4 Lotte van den Heuvel

Fig. 0.2, Fig. 1.5, Fig. 3.1, Fig. 10.1 Pascal Gunsch ISBN:

2

978-0-9557163-0-0


Ice Age Pascal Gunsch, Lotte van den Heuvel, Maarten Hoogstad, Selina van Luik, Ramona van Marion

3


Table of Contents

Table of Contents ........................................................................................................................... 4 Introduction................................................................................................................................... 6

General Stuff ............................................................................................................................ 7 Units .............................................................................................................................................. 8 Geological time scale...................................................................................................................... 9

The Greenhouse Effect ...................................................................................... 10 Consequences ............................................................................................................................... 13 Prevention..................................................................................................................................... 14

Part I Causes........................................................................................................................... 17 The Milankovitch Theory .................................................................................. 18 Seasons ......................................................................................................................................... 19 Obliquity ...................................................................................................................................... 20 Axial Precession ............................................................................................................................ 21 Eccentricity .................................................................................................................................. 22 Apsidal Precession ....................................................................................................................... 24 Orbital Inclination ....................................................................................................................... 25

Albedo ............................................................................................................... 26 Atmosphere Composition.................................................................................. 28 Solar Variations ................................................................................................ 30 Geographical Causes ......................................................................................... 32 Continents.................................................................................................................................... 33 Sea level ....................................................................................................................................... 35

Human Causes .................................................................................................. 36 The Oxygen Cooling........................................................................................... 40 The Fern Cooling ............................................................................................... 42 The Dust Cooling ............................................................................................... 46 4


Part II Icefluence ...................................................................................................................49 Temperature ..................................................................................................... 50 Humanity .......................................................................................................... 54 Transport ..................................................................................................................................... 56 Industry ........................................................................................................................................ 57 Economy ...................................................................................................................................... 58

Geographical Issues .......................................................................................... 60 Landscape ..................................................................................................................................... 61 Sea levels ...................................................................................................................................... 64 Continents.................................................................................................................................... 65 Conclusion ................................................................................................................................... 66 Logbook ....................................................................................................................................... 68

5


Introduction This book is a physics assignment. It is due to a movie we watched, ‘the day after tomorrow’. We had to analyse the plot. After that, we decided to research the causes and effects of a new ice age. We divided everything in 5 main categories: 

meteorological/astronomical/ influences

physical/chemical influences

geographical influences

biological/ecological influences

human/economical/industrial influences

(general stuff)

We divided the tasks, so that everyone had an ‘influence’. We also set a deadline. However, we thought it had to be finished later than our teacher did, which led to conflicting deadlines and limits. We revised everything and set a new deadline. You can see who did what on page 2. As told before, we investigated the causes and effects of a new ice age. Part I therefore contains causes, and part II the effects. The general stuff in mentioned before those parts. I hope you’ll close this book with positive thoughts,

Pascal

6


General Stuff

7


Units Here is a closer look at all familiar and unfamiliar units (and percentages) used in this book. Familiar units: °C – m – g – s – % Unfamiliar units: K – a – ppmv K:

Kelvin, used for temperature. K is derived from °C. Kelvin = Celsius + 273.15 Celsius = Kelvin – 273.15

a:

annum, the Latin equivalent of the word year. 1 a = 1 year When the SI-prefixes are applied (k, M, G), it can also mean years ago. a

annum

one (100) year (ago)

ka

kiloannum

thousand (103) years (ago)

Ma

megaannum

million (106) years (ago)

Ga

gigaannum

billion (109) years (ago)

ppmv: parts per million volume, so 0.0001% volume. For example, 1cm3 CO2 in 1 m3 dry air

8


Geological time scale Eon

Era

Period

Start Ma

Quaternary

2.6

Neogene

23

Main Events (glaciation, climate, etc.) (Ma) 1850CE 1816CE 1400-1850CE 12 ka 2.3 2.6

Cenozoic 34 49 Paleogene

65

Cretaceous

145

Jurassic

200

Triassic

250

Permian

299

Carboniferous

359

Devonian Silurian

416 444

Ordovician

488

Cambrian

542

Ediacaran

630

Cryogenian

850

Tonian Stenian Ectasian Calymmian Statherian Orosirian Rhyacian

1 000 1 200 1 400 1 600 1 800 2 050 2 300

Siderian

2 500

Phanerozoic Mesozoic

Paleozoic

Neoproterozoic

Proterozoic

Mesoproterozoic

Paleoproterozoic

Archean

Hadean

Neoarchean Mesoarchean Paleoarchean Eoarchean

2 800 3 200 3 600 3 800 4 570

56 65 65

251 360–260 360–260

460-430 460-430 530

CO2 – 280 → 390 ppmv Industrial Revolution Year Without a Summer Little Ice age Last glacial ends Homo habilis (humans) Start Quaternary glaciation CO2 – 100 ↔ 300 ppmv Icehouse climate CO2 – 650 → 100 ppmv Warm but cooling climate Azolla event (CO2 – 3800 → 650 ppmv) Moderate, cooling climate Climate tropical First large mammals Dinosaurs extinct CO2 – 385 ppmv (present) First mammals, birds CO2 – 1500 ppmv First Dinosaurs Permian-Triassic extinction The Karoo Ice Age Formation Pangaea The Karoo Ice Age O2 – Highest ever Andean-Saharan glaciation Andean-Saharan glaciation First green plants Cambrian Explosion CO2 – 6000 ppmv

650-635 750-730

Marinoan glaciation Sturtian glaciation

2 050 2 400-2 100 2 400-2 100 2 500

atmospheric oxygen Huronian glaciation Huronian glaciation GOE

3 200 3 600 3 800 4 533 4 570

First Stromatolites First phototrophs First life Formation of Moon Formation of Earth

9


The

Greenhouse

Effect

What are the causes of the greenhouse effect? What are the consequences? Can we do something to stop it?

10


The warming of the Earth is the opposite of what would happen during an Ice Age (or icehouse effect). The most important factors are of course the atmospheric composition, also known as the greenhouse effect. The atmosphere has the most influence on the temperature on Earth than anything else. In early times, when the atmosphere wasn’t formed completely yet, it was really warm on the Earth. This could be a sign of what is happening now, that we will lose our atmosphere again. The greenhouse effect is the most well-known effect for the warming of the Earth. Scientists are 90% sure this is the most important cause. The high level of CO2 is our biggest problem. The temperature on Earth has raised 0.8 °C in the last century, and two-third of it was during the last 3 decades. The industrial revolution was huge at that time, and even more factories are coming. Most of these factories produce a high amount of CO2, which they release in the air. Drillings in Antarctic ice have proved this too. It shows that the amount of carbon dioxide hasn’t been higher than 300ml/m3 in the last 650.000 years. You can clearly see that amount going up when the industrial revolution started. Usually the Earth only gets its warmth from above the clouds, from the Sun. And the total amount of that is only reached at the top of the atmosphere (TOA), 50% of it is absorbed by the surface of the Earth. It is send to us in a form of UV, which is close to IR radiation. Because of the warmth, the Earth radiates a higher IR thermal radiation. This kind of radiation has longer wavelengths than IR radiation. These waves go up and between the Earth and its atmosphere. Because of all this warmth that is trapped the average temperature everywhere on Earth will rise. If there are a lot of factories on one place it doesn’t just affect that one place, but the whole atmosphere. In fact this is just a small summary compared to the complexity of the whole greenhouse effect. The energy that is absorbed warms the surface. Simple explanations tell us that this warmth is lost as thermal radiation. The atmosphere close to the surface barely gets any thermal radiation (with the exception of “window” bands). The most loss of heat is caused by sensible heat and latent heat transport. Sensible heat could cause a change of temperature, but latent heat transport can’t. The loss of this radiative energy becomes very important because the water vapour in the atmosphere is decreasing; water vapour is a really important gas in the atmosphere.

11


Fig. 0.1 – a diagram of the greenhouse effect.

Now the greenhouse model is explained a little better, and it becomes more realistic. The Earth gets warmed to a temperature of about 255 K (the property of this is Kelvin; you can also measure it in Celsius). It radiates long wave-lengths now, IR heat between 4-100 μm. Remember the Sun only radiates between 0.2-4 μm. With these kind of wavelengths, greenhouse gases that were transparent to IR aren’t anymore (like Ar). Each layer of atmosphere the warmth passes more atoms absorb the heat of it, the heat that is radiated upwards from the layer underneath. To stay true to its ‘normal habit’, it wants to get rid of this warmth as soon as possible. It sends out all the radiation it has in every direction that is possible. This means there is also more warmth from below. But it is still radiating back out into space from the upper layers to maintain its own ‘normal habit’. Because of the increasing amount of concentration of these gases also the absorption and sending out from the warmth increases. Therefore it warms the layers even more and eventually the surface below. Greenhouse gasses include most gases with two different atoms (for example: carbon monoxide, carbon dioxide) and all gases with three or more different atoms. These gases are able to absorb and send out infrared radiation. But most of the atmosphere, more than 99%, is transparent to infrared radiation. The main atoms are N2, O2 and Ar. These consist out of only one type of atom, and therefore they don’t directly absorb or send out IR.

12


Consequences A severe warming of the Earth could have many consequences. The first and most obvious of course, is that the average temperature of the Earth will rise. At first this won’t cause many problems for anyone of course. But the pollution of the air could cause some problems. It wouldn’t only cause problems to human, but also to other animals and plants. Nothing that is on the Earth right was made for higher temperatures than they are used to now, even a cold winter or a really hot summer can cause a lot of damage to animals and plants. We can already see that nowadays. The pollution of the Earth will be a long-term problem. We won’t see much of the consequences of it soon, but if we go on like this we will. Most importantly the air we breathe in. Humans and animals mostly breathe in O2 and a lot of the air we breathe in and out consists out of N2 too. If these gases are changed by the greenhouse effect it could be dangerous. It definitely isn’t good for anyone to breathe in radiated gases. But it will probably take quite some time before the concentration of radiated O2 and N2 is high enough for that. Plants also suffer from this. Plants make use of photosynthesis, which is important for us too. If they aren’t able to get in the right concentration of air, many plants will die which is bad for us again. We should be really careful with our plants. Some of the consequences are already visible for us. We all know the ice on the North Pole and the Antarctic is melting. This means the sea level is rising, which would cause a lot floods everywhere. The effect these floods will have will be immense. Water exists on almost every part of the Earth, so if the ice or the snow on the mountains melts, it can soon be everywhere maybe even in places we wouldn’t even expect it to be at. It does have one good consequence though, because the water that is now frozen is the water we use to drink right now. We shouldn’t use all the water of course, but there are places on this Earth which do need more water and if it does get warmer everyone will need more water to drink. There might be one good consequence though. It will be very unlikely for a new Ice Age to happen. But it could be very dangerous if the schedule of the Earth is messed up, you can’t have a warm period and a very cold period at exactly the same time (see: Milankovitch cycles). One question will probably remain forever: will the warming of the Earth or a new Ice Age have more effect on life as we know it now on Earth?

13


Prevention The warming of the Earth is something we could prepare ourselves for, but it would be even better if we prevented the worst at all. The most important preparation has to be the reduction of the CO2 and other dangerous greenhouse gases. We have to look at the biggest sources of CO2, which are probably most factories. We already try to make those factories less polluting, but most of them don’t even have the money for that. To change all factories on Earth, it will take quite a lot of time and also a lot of money. Right now, we are all focusing on the CO2 but we shouldn’t forget the other gases too, like the big amount of methane that is now hidden under the ice of Canada and Russia. We have to make sure that either that ice will stay, or that we have a good place to make use of all this gas. We also have to be careful with our plants, they are more important than some people might think they are. They provide us oxygen and food, which are both necessary to live. If the warming continues, we could decide to put more plants in greenhouses. We could also cultivate them in a way they are better at resisting warmth so we can still make use of them. It is probably better to put the plants we use for oxygen outside and make them better at resisting the warmth and keep the plants we use for food inside and don’t change too much about them. Who knows what happen if we change the composition of those plants, they might become unhealthy or even poisonous. The water is also something we should prepare us for. Right now it is still ice, but it is also at places we can barely get ourselves. The ice on the North Pole is already melting, and it is possible for the sea level to rise. Countries that lay underneath that sea level are in great danger. In the Netherlands we could for example make our dikes higher, but that is a lot harder for a whole country which is totally unprepared at the moment. It is probably not possible to save all these little islands, but if we don’t try we will never know.

14


Annual CO2 Emission

Industry Traffic Households Trade, Services, Government Agri- & Horticulture Other

Fig. 0.2 – Where does our CO2 originate?

15


16


Part I

Causes What could cause an Ice Age? Below, a diversity of aspect is taken into consideration.

17


The

Milankovitch Theory Milutin Milanković (Serbian: Милутин Миланковић) was a Serbian mechanic and geophysicist. He was born in Dalj (present-day Croatia) the 28th of May 1879 and he died there December 12th, 1958. He studied mechanics in Vienna, but he dedicated his life to formulating mathematical theories on varieties in Earth’s orbit. Milanković published his work in several papers from 1912 till 1920. He described 5 varieties that could cause climatic cycles, known as Milankovitch cycles. These five factors are obliquity, eccentricity, axial precession, apsidal precession and orbital inclination. Before we can understand the influences of Milankovitch cycles on our climate, we must first understand the force driving the seasons.

18


Seasons

Fig. 1.1 – a representation of Earth’s obliquity and the density of sun rays.

Earth has a small tilt, called the axial tilt or obliquity. Earth’s obliquity is about 23.5° at the moment. This feature is also shown on globes (and in Fig. 1.1). Due to this tilt, one hemisphere (in case of Fig. 1.1 the Southern) receives more light and warmth per m2, or in difficult words more insolation. Therefore it’s summer on the Southern Hemisphere, and winter on the Northern. We call this situation a solstice. If the sun were on the other side, it would have been summer on the Northern hemisphere and winter on the Southern (see Fig. 1.2). However, in some cases it is harder to distinguish the seasons. Take position 4. The incoming energy is equally big on both hemispheres. We call this situation an equinox.

4

3

1

2 Fig. 1.2 – 1: winter solstice, 2: vernal equinox, 3: summer solstice, 4: autumnal equinox.

Knowing how the seasons work, we can think about ways to change the climate (for example by change of the obliquity). There are however other factors to be taken into account. These factors will be discussed in the next paragraphs.

19


Obliquity We already know that obliquity is the same as axial tilt. We also know that axial tilt is the angle a planet is tilted, in Earth’s case 23.5°. To illustrate its essence in Earth’s climate, you’ll see some tilts of other planets in Fig. 1.3.

Fig. 1.3 – obliquity of the 8 planets (note: a smaller obliquity means a steadier climate).

Earth’s axial tilt is, due to gravitational forces, not always the same and has a range of 22.1° to 24.5° (See Fig. 1.4). It takes about 41 000 years to shift between a tilt of 22.1° to 24.5° and back again. When the obliquity decreases, it implies a decrease in summer insolation, but an increase in winter insolation. Conversely, when the obliquity increases, insolation during summer increases, and during winter decreases.

Fig. 1.4 – the 22.1°-24.5° range of Earth’s obliquity

The magnitude of these changes depends on the latitude. At high latitudes, the mean insolation increases with an increasing obliquity, while lower latitudes have a decrease in mean insolation. These changes imply cooler summers. These events may trigger an ice age, as cooler winters precipitate more and cooler summers melt less. Also, a decreased obliquity means a decrease in summer insolation, and a decrease in mean insolation at high latitudes (where most snow/ice can be found). Earth is currently tilted 23.44°, which is roughly halfway between the extreme values. The tilt is now in its decreasing phase, and reaches the minimum value around 10 000 CE. This means that the winters get warmer and summers cooler, with an overall cooling. This could trigger an ice age. 20


Axial Precession When you ever get the change to stand on the North Pole and you look directly above you, you’ll see a star called Polaris (or North Star). When you’d visit exactly the same spot some thousand years later, and do exactly the same as you did before, you would not see Polaris anymore. This is because Earth wobbles. The wobble is called axial precession. It takes about 26 000 years to complete one full wobble. It is caused by gravitation exerted by the Sun and Moon

Fig 1.8 – Earth’s axial precession

The wobble causes minor changes in the seasons. This is because the direction of our tilt is altered during every orbit around the Sun. For example, when the axis points towards the Sun in perihelion, the northern hemisphere will receive more insolation. Also, the winter will receive less insolation. The summers are hotter, and the winters are colder. For the other hemisphere, it’s all vice versa; it will face hotter winters and colder summers. Currently, perihelion occurs during our winter (northern hemisphere), and aphelion during our summer. We have, therefore, hot winters and cold summers, while the southern hemisphere has hot summers and cold winters. These effects are less extreme than shown before, but still noticeable.

21


Eccentricity Eccentricity is the same as the rate in which an orbit is different to a circle. You can see a schematic drawing of Earth’s orbit in Fig. 1.5. The orbit is an ellipse. We call Earth X, and the Sun F1. Point A, closest to the Sun, is called perihelion. Point B, furthest from the sun, is called aphelion.

Fig. 1.5 – a schematic drawing of Earth’s orbit. Earth = X, Sun = F1

Now we need some mathematics to calculate the eccentricity. We first have to name the parts of an ellipse. In Fig. 1.5; AB is called the major axis, AM the semi-major axis (we call this a) and MC the minor axis (we call this b). Eccentricity is expressed with the letter ε. There are some given eccentricities. For a circle, ε = 0, for an ellipse, 0 < ε < 1, for a parabola, ε = 1, for a hyperbola, ε > 1 and for a line segment, ε = ∞. The formula for

Fig. 1.6 – formula for eccentricity

eccentricity is shown in Fig. 1.6. Now we have an idea on what eccentricity actually is, and what Earth’s orbit looks like, we can focus on orbital eccentricity.

22


Earth’s Orbital Eccentricity Earth’s orbit varies from nearly circular to elliptical. Its mean eccentricity is 0.028. The present eccentricity is 0.0167. It takes about 100 000 years to change from a low to a high eccentricity. Right now we are in the decreasing phase. Eccentricity is caused by the gravitational fields of Jupiter and Saturn.

nearly circular (ε = 0.005) Fig. 1.7 – different orbits

elliptical (ε = 0.058)

So, when eccentricity increases, the orbit becomes more elliptical. This means that the semi-major axis, the minor axis or both should change. A given fact is that the semi-major axis of planets remains unchanged. Therefore, a year remains the same too (see Kepler’s 3rd law). If the semi-major axis does not change, it must be the minor axis to change, and it does so. When the minor axis decreases because the eccentricity increased, the seasonal changes increase. The solar irradiation at perihelion compared to the irradiation at aphelion is slightly larger than 4 times the eccentricity. Using this we can easily calculate 0.0167 × 4 = 0.067, which is corresponding with our present day difference of 6.8%. When the eccentricity is at its maximum (0.058), the difference in irradiation is 0.058 × 4 = 0.232, which is corresponding with a mean difference of 23%. When the eccentricity is at its maximum, the orbital motion differs more and the lengths of the seasons change. The parts nearest to perihelion receive more gravitational force from the Sun, and orbit faster. This means that, if for example autumn and winter occur near to perihelion, they are slightly shorter than spring and summer. We can state: an increasing eccentricity lengthens the time spent at aphelion, but shortens the time at perihelion. Kepler’s Third Law T = time, a is average distance to Sun.

23


Apsidal Precession Consider Earth’s orbit as a hula hoop and the Sun as your waist. Just like the hula hoop shifts around your waist, Earth’s orbit ‘shifts’ or precesses around the Sun. For you it takes but a second to hula hoop, while the Earth is a bit slower, it takes 21 000 years to complete a cycle. Apsidal Precession plays a minor role in Earth’s climate, together with Earth’s Eccentricity.

Fig.1.9 – it takes Earth about 10 000 years to go from the left image to the right.

Fig. 1.10 – a diagram showing the four phases of apsidal precession.

24


Orbital Inclination If you’d take the orbits of all eight planets, and average them, you’d create what we call the (Laplace’s) invariable plane. Jupiter is roughly like placed on this plane. However, Earth is ‘tilted’ or inclined from the invariable plane. Earth has an inclination of 1.57°; however, not all planets do. Also, the inclination changes over time in cycles of 100 000 years. The inclination can be as much as 3°. Higher Inclination implies a higher obliquity (see Fig. 1.12). Originally, this factor was not part of Milanković’s theory. It is however added to the Milankovitch Cycles, as it impacts the amount of insolation and follows the well-known

Fig. 1.11 – Inclination.

100 000 year pattern.

Fig. 1.12 – Earth’s orbital inclination as seen from the side.

25


Albedo

26


Albedo is the reflecting power of a specific surface. There are different ways to express it, sometimes it is expressed in percentages but it can also be expressed in a scale of 0.0-1.0. Albedo does depend on the amount of radiation that is reaching the Earth. Albedo is very important in both astronomy but also when it comes to climates. The name is derived from a Latin word where it means whiteness. Typical Albedos Asphalt 12% 8%‒15% Conifer forest Deciduous trees 15%‒18% Bare soil 17% Green grass 25% Desert sand 40% New concrete 55% 50%‒70% Ocean Ice Fresh snow 80%−90% Fig. 2.1 – some typical albedos. The average albedo of the Earths is between 30%35%. This is called terrestrial albedo. When you look at the Earth in general, you can see that both oceans and forests have a low albedo. From all the other landforms, deserts have the highest albedo of all. Mostly the albedo of landforms is between 10%-40%. That the total albedo of the Earth is in fact is higher than the average amount of albedo on the surface, has

Fig. 2.2 – some typical albedos in a graph.

to do with the contribution of the clouds. The reflectance of a black sky is sometimes called the directional-hemispherical reflectance, and the white sky albedo is sometimes called bi-hemispherical reflectance. It is a fact that humans have changed the albedo of the Earth, but it is very difficult to say if it makes a difference. There is also something called astronomical albedo. Just like the Earth, other planets, asteroids and satellites have an albedo too. You would say our moon has a high albedo, but with an albedo of 12% it is even lower than the Earth’s albedo. If the Earth does get colder, it won’t just be gone after a short period. The snow and ice that will be on Earth has a high albedo, causing a huge feedback of the temperature. Once it’s cold, it will stay cold. More ice will cause the albedo to increase, less sunlight will be absorbed and the temperature will be decreasing. But this could also happen the other way around. When an area where there used to be a lot of snow and ice melts, the albedo decreases. This means more sunlight is absorbed by the surface of the Earth and the temperature will keep increasing causing more ice to melt and so on. We will be in a cycle of warming.

27


Atmosphere Composition

28


Atmoshpere Composition Nitrogen (N2) Oxygen (O2) Argon (Ar) Carbon dioxide (CO2) Neon (Ne) Helium (He) Methane (CH4) Fig. 3.1 – Earth’s Atmosphere Composition.

Changes in the atmosphere of the Earth are a really important thing when it comes to changes of temperature. There is prove that the amount of greenhouse gas started to drop at the start of an Ice Age, and came back again when the ice was starting to disappear. But there is no one who can tell us why exactly it happened and why it happened at that specific moment.

Typical GWPs Gas Formula GWP Carbon dioxide CO2 1 Methane CH4 25 Nitrous oxide N2O 298 CFC-12 CCl2F2 10 900 HCFC-22 CHClF2 1 810 Tetrafluoromethane CF4 7 390 Hexafluoroethane C2F6 12 200 Sulphur hexafluoride SF6 22 800 Nitrogen trifluoride NF3 17 200 Fig. 3.2 – global warming potential of typical greenhouse gases over a 10o-year horizon.

The greenhouse effect has also had its effect in earlier climate changes, but now that it is so severe it becomes more and more important, especially the changes in the composition of the greenhouse gases. The atoms which are now transparent will get less transparent so they will radiate more warmth. It is clear this is one of the causes of the changes of the temperature on Earth. One thing is for example that CO2 won’t dissolve in water as well as it did before when the temperature rises. If the composition of the CO2 stays the same, it will take thousands of years for us to see any changes, but if the level of CO2 goes up we could already see the difference in less than 40 years. Gas hydrates could also cause a difference in the temperature, but the Earth already needs to be warm enough before it can happen. Some parts on Earth are always frozen, for example in Canada and Russia, and under that ice there is stored a big amount of methane (CH4). Because of this permafrost, it is not possible for these gases to radiate their energy. If everything would come out all at once, the Earth would have a lot of methane at one moment.

29


Solar Variations

30


In earlier times other things had an effect on the warming of the Earth. This is called solar variation. Because of the big greenhouse effect, we aren’t really sure how much of a difference this still makes in the warming of the earth. There have been warmer times on Earth before, but not on a regular scale like ice ages did. Solar variations could also be a cause of cooling the Earth. Solar variations affect the temperature in different ways. If solar activity, more Sunlight, and also greenhouse gases would increase the troposphere was expected to warm. The troposphere is the lowest part of the Earth’s atmosphere. An increase of the solar activity would warm the stratosphere and only an increase of greenhouse gases would cool the stratosphere down. The stratosphere is the second layer of the Earth’s atmosphere, just above the troposphere. Data have shown that the stratosphere has cooled down after the first measurements. This would mean the amount of greenhouse gases has increased. That it can warm the Earth, means it can cool the Earth down too when the solar activity is less. The Sun also has cycles, called solar cycles. But once again, there is no definitive link between the temperature on Earth and the activity of the Sun. From the 15th till the 19th century our planet had to deal with an Ice Age, called the Little Ice Age. A part of this Ice Age coincided together with the Maunder-Minimum (1645 - 1715). On average the solar activity didn’t increase for 50 years and in 2009 it broke a low record from more than a century old.

Fig. 4.1 – the Maunder minimum.

Cosmic rays from space have so less effect on the temperature there is no need to explain these. Studies have showed that the solar activity might be slowing down, which means that there could come a new solar cycle. But yet there is no definitive link between solar activity and global

Fig. 4.2 – atmosphere.

temperatures.

31


Geographical Causes 32


Continents The continents weren’t always as they are now. We know them different than thousands of years ago. The continents are constantly moving. You cannot see, feel, hear, smell or taste the movement of the continents. But that doesn’t mean that they don’t move! Pangaea was a supercontinent from very long ago. It was 1 continent consisting out of all continents we know nowadays. Pangaea comes from the Greek words παν γαια They mean ‘entire’ and ‘earth’. There was also 1 big ocean; Panthalassa, which comes from the Greek word θαλασσα. That means ‘sea’. Later, Pangaea split up in the continents from now. That was because of the moving fluid underneath the crust. There has been (at least 1) more supercontinent(s) in history. Next to Pangaea there was also supercontinent Rodinia.

Fig. 5.1 – Pangaea.

33


The continents are lying on a sort of liquid underneath the crust of the earth. As you possible know, liquid moves. Look at water, it streaming in a direction. That also happens with the liquid underneath the continents. That makes that the continents move. Here are some reasons why continents might cause an ice age: 

If the continents move much, for example Europe, it can be lying on the place of a desert and become extremely dry. Then, all the factories might not work and break down. Or cars cannot drive anymore because there is not enough oil there or because of other reasons, there will be less CO2. The earth would become cooler therefore. If the continent Europe moves to a colder place, it might freeze up and there will be an ice age. The change that this will really happen is very small and it will take centuries before Europe would be on a place that far away.

In a nuclear war, continents might get totally destroyed and cities will be lost. So, cars and factories will break down. The earth will become cooler and some parts of the world might freeze up. Let’s hope it will not go like this!

Another theorem: when the earth stops rotating around the sun and itself, continents will be extremely hot or extremely cold. The parts where it’s cold may form ice continents. But if you can call that an ice age?

As you have read, none of those theorems are very likely. Will there be an ice age because of the continents? That seems to be not the case. There have been a lot of ice ages and they had a kind of pattern, which might conclude that more ice ages will follow the last ones. But the continents will not be a main cause for an ice age.

34


Sea level The sea level rises because the earth is too warm. The poles can’t stand that warmth and melt. That water streams in the oceans and the sea level rises. But can that cause an ice age? That’s what we’re going to discuss right now.

 Fig. 5.2 – sea level rise.

When there is ice, it’s cold, it’s freezing. So when there is an ice age, it must be cold too. But now, the earth becomes warmer and warmer. Like already told, the poles melt because of that warmth. The poles are made of ice, which is frozen water. When it melts, it becomes water again. So that water comes in the oceans and seas and causes the sea level too rise. When the sea level continues to rise, land will flood. That makes cars crash and break factories down. These things cause CO2 and that makes the earth becoming warmer. So if they are out of order, the earth might cool down. It might become so cold (once there came an ice age because of the temperature decreased 4 degrees), that the sea level causes an ice age and it will also cause the poles to freeze up again. There will be a lot of ice on the world then! But when the sea level stop rising, and becomes lower, the land will not flood. And it will not cause the earth too cool down. This will make the poles melt and make the sea level rise again. So when the sea level decreases, the change is very small that the sea level is the cause of a new ice age. But it can cause the sea level too rise again. And that causes an ice age, so you can say that the decreasing of the sea level in a way causes an ice age too. But not in a direct way.

35


Human Causes The effect on the climate by humans is critical. People pollute the environment too much with the production of too much waste products such as: CO2 and other chemical waste.

36


People make great campaigns against pollution but they donâ&#x20AC;&#x2122;t entirely solve the problem. There must be a strict law with high fines for production of waste that is very bad for the environment. Air pollution is one of the most dangerous types of pollution because it will affect peopleâ&#x20AC;&#x2122;s health and also the ozone layer. Due to air pollution there are huge holes in the ozone layer and the ozone layer protects us from the ultraviolet radiation. So when there are holes in the ozone layer it cannot protect us anymore and more people will suffer from skin cancer.

Fig. 6.1 - Sunlight passes the ozone layer, and so does the ultraviolet radiation.

Many people are trying to reduce the amount of CO2 made by inventing cars that can run on alternative fuel and that is working out quite good. However that would not be enough to stop the whole air pollution. Many factories pollute the air too and it would be difficult to let a factory run on alternative fuel.

37


As written in the page before pollution is caused by many different factors: 

Humans; we pollute the air with harmful gases.

Chemical waste dumped in a not thought through way and leads to pollution of the ground.

The CO2 made by humans in such an amount that it thins the ozone layer and also lead to holes in the ozone layer.

We are going to focus on the last factor. Because there are holes in the ozone layer the sun radiation isn’t hold back anymore and can pass right through the ozone layer. The sun radiation disturbs the magnetic field of the earth. This may lead to shifting of the magnetic poles and this will eventually cause an ice age because in fact the earth’s position has changed.

Fig. 6.2 – a diagram of Earth’s poles.

38


39


The

Oxygen Cooling Let’s take you back to what is not only largest glaciation ever, but also the worst mass murder in history. It all started with oxygen.

Oxygen (O) is an atom with its atomic number 8. It’s a non-metal, and a gas at room temperature. It melts at 54.36 K, and its boiling point is at 90.20 K. About 19% of Earth’s atmosphere is filled with oxygen molecules (O2). Oxygen is also found in water (H2O) and in the greenhouse gas carbon dioxide (CO2). Parts of Earth’s crust contains oxygen compounds, such as silica (SiO2) which is found in granite and sand, aluminium oxide (Al2O3), which is present in bauxite and iron(III) oxide (Fe2O3), found in rust.

40

Fig. 7.1 – An O2 molecule


About 3 600 million years ago, during the Paleoarchean, the first known oxygen-producing organisms (mainly bacteria, such as the cyanobacteria), or in different words phototrophs, were found. They use sunlight, carbon dioxide (CO2) and water (H2O) to form glucose (C6H12O6), with oxygen as a combustion product. This process is called photosynthesis, and can be expressed as: 6 CO2 + 6 H2O + sunlight → C6H12O6 + 6 O2 This reaction produced oxygen, but the oxygen was only present in small quantities. This continued for about 1 400 million years. When 2 500 million years ago the oxygen levels became higher, free oxygen became available in the atmosphere. We refer to this event as the Great Oxygenation Event (GOE). Also, the phototrophs wiped out all anaerobic species of that time.

Fig. 7.2 – a graph showing oxygen levels in the atmosphere. stage 1: first phototrophs, stage 2: GOE

But more importantly, the free oxygen began to oxidise methane (CH4), a greenhouse gas 25 times stronger than carbon dioxide. This is a formula for the reaction: CH4 + O2 → CO + H2 + H2O The resulting hydrogen oxidises, 2 H2 + O2 → 2 H2O As does the resulting carbon monoxide 2 CO + O2 → 2 CO2 We can summarise above to and easier formula: CH4 + 2 O2 → CO2 + 2 H2O Every reaction, the greenhouse effect is deduced 25 times. This is believed to be the cause of the Huronian glaciation, a period from 2400 Ma to 2100 Ma. During the Huronian glaciation, the Earth probably was in a ‘snowball’ Earth phase. This means that the whole Earth is covered with snow.

41


The

Fern Cooling Still today weâ&#x20AC;&#x2122;re in an ice age. An ice age knows glacial periods and interglacial periods. Glacial periods are cold, snowy and characterised by low temperatures. An interglacial is an interval of warmer temperatures. But, What caused the ice age this time?

Background â&#x20AC;&#x201C; The Azolla filiculoides (or commonly known as Water Fern) is a modern descendant of the Paleogene Azollas.

42


About 49 million years ago, during the Eocene epoch (part of the Paleogene era) the world looked different then now. At first, the climate was much hotter, with about the same temperature on both the equator and the poles. There are fossils from the Arctic area, which suggest that there were mixed conifer-broadleaf rain forest, supporting animals like alligators, mammals,

including

brontotheres (Fig.

8.1),

turtles, and diverse primates, and

the

tapirs,

Fig. 8.1 – a reconstruction of the Megacerotops (a Brontotheres genus).

hippo-like

Coryphodon (Fig. 8.2). These are all tropical life forms, which require a temperature higher than 22°C, and with about 20 hours of sunlight a day, this seemed to be no problem. It was, as you can call it, a greenhouse Earth, with about 0.38% of Earth’s atmosphere filled with CO2. Also, the continental configuration was different then it is now. If you’d look at the Arctic Sea, you could conclude that it is ‘closed off’ from the rest

Fig. 8.2 – a reconstruction of the Coryphodon.

of the seas. Because of this, no cold currents could come over there and, the water only warmed, creating a perfect tropical environment. The Arctic Sea warmed and evaporated a lot, increasing the density of the sea. The rivers that fed the basin, filled with the low densed freshwater, formed a nepheloid layer (a layer of fresh water) on the surface of the Sea. This nepheloid layer would be mineral (e.g. Phosphorus) rich, as it had already crossed a lot of earth and mud.

Fig. 8.3 – a reconstruction of the Arctic Rainforest.

43


Fig. 8.4 – continental configuration during the Eocene epoch.

Azollas can draw down as much as a tonne of nitrogen per acre per year (0.25 kg/m²/a). This is matched by 6 tonnes per acre of carbon drawdown (1.5 kg/m²/a). Azollas use nitrogen for growth, and there’s a lot of nitrogen in the air (79%). They only limit in their growth can be phosphorus. This is because phosphorus is required for DNA. If these are combined with a moderate temperature and 20 hours of sunlight, the Azolla biomass can double within three days. All the conditions described above – the temperature, 20 hours of sunlight, nitrogen and carbon dioxide rich atmosphere, fresh water, no circulation, and the mineral (Phosphorus) rich water – are a perfect match with Azolla’s needs. There came huge blooms of Azolla in the Arctic Sea, and they only grew due to their asexual reproduction. As more Azollas lived, more Azollas died. When they died, they took some carbon dioxide with them and sank down to the higher densed, anoxic part of the Sea. Here they could not rot and eventually, they all became part of the fossil record (including their carbon dioxide), or made into oil. Global carbon dioxide levels were reduced from 3800 ppmv to 650 ppmv. This is known as the Azolla Event. It reduced

the

greenhouse effect and caused an icehouse Earth we are still in.

Fig. 8.5 – the Arctic Sea probably looked like a giant garden pound.

44


45


The

Dust Cooling A new theory says that all you need, to start a new Ice Age on Earth, is dust.

46


When iron rich dust would be blown into the sea, the iron rich dust would react on the plankton. The plankton would, because of that, take up large amounts of carbon dioxide from the air. They even think it would be a solution for the greenhouse effect. Algae bloom through iron rich dust. It is not new that when iron rich dust comes in contact with the surface of the ocean, that the reaction is algae bloom. When the number of algae increases they take huge amount of carbon dioxide up from the water. The ocean will take carbon dioxide up from the air. In this process, the amount of carbon dioxide in the air will decrease and in this way they say it will help to reduce the greenhouse effect. At this moment, the climate is dry and warm. This dry and warm climate causes a very few dust storms. Observations of the ice of the Antarctic Ice, which can be 800.000 years old, said that the air in these Ice Ages were twice as more dusty as they are now. This was a combination with lower carbon dioxide percentages. Algae bloom causes a decrease of the temperature. Many climate scientists think that dust storms are the key for the last Ice Ages many years ago and maybe the ones for the future. When huge amounts of land get dryer and dryer, the air becomes dustier and in this way there will be more iron in the ocean, because of the dust storms. At this moment is the Southern Ocean, the Pole Ocean around Antarctica, in many ways a biological dessert. The reason for this is the amount of iron in the ocean. There is a lack of iron. When huge amounts of iron would be blown into the sea, the algae would grow and would take up much carbon dioxide. And when the amount of carbon dioxide decreases, the temperature would also decrease. When there would be dust storms and the dust would blow into the Southern Ocean, the algae would grow and this could be the start of another ice age. This will stay for about thousand years. After these years the cooling stops for a certain unknown reason. They think of the Milankovitch cycles. The result of this: The dust storms stop, the algae die of hunger and the amount of carbon dioxide will increase.

Fig. 9.1 â&#x20AC;&#x201C; temperature variation compared with dust concentration.

47


48


Part II

Icefluence How does an ice age influence diverse aspects mentioned above?

49


Temperature Changes in the temperature are probably one of the first things we will notice if thereâ&#x20AC;&#x2122;s coming a new Ice Age.

50


Mean Temperature 1901 - 2011 12 10 8 6 4 2

1901 1904 1907 1910 1913 1916 1919 1922 1925 1928 1931 1934 1937 1940 1943 1946 1949 1952 1955 1958 1961 1964 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997

0

mean temperature 1901-2011. There is a steady line.

Mean Winter Temperature 800 - 1990

800 840 880 920 960 1000 1040 1080 1120 1160 1200 1240 1280 1320 1360 1400 1440 1480 1520 1560 1600 1640 1680 1720 1760 1800 1840 1880 1920 1960

4 3,5 3 2,5 2 1,5 1 0,5 0

mean winter temperature from 800 till 1990. There is some kind of a steady line, with peeks (800, 1200, 1990) and troughs (900, 1320, 1800, and 1550-1800). Fig. 10.1 â&#x20AC;&#x201C; recent temperature changes projected in two graphs.

51


Our climate has had more huge changes of temperature. In the last 2.6 Ma there were more big ice ages. Those ice ages were interrupted after 100.000 years by a warmer period of about 10.000 years. The ice ages are actually called glacial periods. So, we actually live in an Ice Age, called the Quaternary Glaciation. In this period there were colder periods. In these colder periods the ice grew and the sea level dropped. An interglacial period is a period between 2 glacial periods. The characteristic of this period is the rising of the temperature. The most recent interglacial period is the one we are living in now, called the Holocene. The Holocene started of about 10.000 years ago and didnâ&#x20AC;&#x2122;t end yet. The periods interchanged with interglacial periods, warmer periods were the ice began to melt.

Fig. 10.2 â&#x20AC;&#x201C; global cooling during the 20th century.

The last interglacial period began about 11.000 years ago. But does this mean that we are entering a new glacial period? If we look at the position of the earth and the expected CO2 in the atmosphere we are positioned in a longer interglacial period than we have ever been in the last 2.6 million years. Even if we take a close look to the ice on the North Pole. The ice is melting and not growing. It the ice starts to grow, than we can say that in the coming 10.000 years the ice is growing for the upcoming Ice Age.

Fig. 10.3 â&#x20AC;&#x201C; a graph showing interglacials.

52


Northern hemisphere

Southern hemisphere Fig. 10.4 â&#x20AC;&#x201C; present day glaciations are indicated in dark grey/black.

53


Humanity

54


Below we discuss the possible influences of an ice age on diverse factors; notably transport, industry and economy. However, this is not the first time we have to deal with a glaciation. The only differences between now and 10 000 years ago are that we have changed our way of living.

Fig. 11.1 â&#x20AC;&#x201C; an artistâ&#x20AC;&#x2122;s reconstruction of an ice age village, 10 000 years ago.

55


Transport Because of the ice age people would not be able to transport themselves and also you cannot transport goods. This will affect the world trade and above all that the world economy –were we are going to talk about a moment later. Oceans could freeze and transport overseas would become impossible and overland it will become too dangerous. And of course flying would be impossible because you cannot take off and land and it is very cold. Maybe when an ice age happens people could invent other means of transportation. People aren’t thinking when they pollute the air and don’t think about the effects and that is why we aren’t prepared for an ice age. If transport becomes impossible we become stuck to where we are because we cannot move ourselves to other places. And if there is no transportation we do not have enough life supplies to keep us alive and we will die out.

Fig. 11.2 – snow is already a problem for transportation nowadays.

56


Industry

Fig. 11.3 – Industry is largely responsible for polluting the air.

If transport would become impossible, the industry will collapse. And this will cause a collapse of the economy. The industry needs transport to import and export goods. Many factories would have to close due to the ice age and this will be bad for many people. They will lose their jobs. You see that an ice age can cause many problems to society. If industry stops the most life supplies cannot be made and –what already said- transport is impossible. Many people will starve of hunger. And of course it is very cold and this doesn’t help the situation. Because of the ice age factories will shut down and there is no transport so there would almost be no greenhouse gases produced so maybe the ozone layer can repair itself, which is a positive factor.

57


Economy The two factors above will be affected by the ice age so automatically the economy will be affected too. Due to the fact that transport will become impossible there wonâ&#x20AC;&#x2122;t be any world trade and that is bad for the economy worldwide. The huge impact on industry is bad for the financials for many individuals and the whole country will suffer from it. Because more people lose their jobs, they can spend less. All the different subjects that will be affected by the ice age work in a spiral downwards, which is projected in Fig. 11.4. Our conclusion is that everyone in the world will suffer from the ice age; not only economical but also on health.

58


Transport is more difficult

Goods become more expensive (inflation)

•The society and industry are affected

Many people will lose their jobs

•Bad for the individual and national finance

People cant afford life supplies

Many people starve due to famine

World economy will collapse and humanity may become extinct

Fig. 11.4 – a downwards spiral about what happens when an ice age occurs.

59


Geographical Issues

60


Landscape Landscape can be a consequence of an ice age too. Some examples are glacial deposits. The Great Lakes (see Fig. 12.1) in Northern America are formed because of an ice age. Not only the Great Lakes, but also the Baltic Sea was formed.

Fig. 12.1 – the Great Lakes.

Another aspect of the landscape is formed by ice ages; erratic’s. Erratic’s are very big stones which come from a glacier. The word erratic comes from the Latin verb ‘errare’ which means to rove. They are brought to another place by the melted ice (water). The water brought the erratic’s to the place where they are now. And they are grinded by the sand in the water.

61


Also hills (drumlins) are a consequence of an ice age. The ice sheet moves over the land and forms a drumlin.

Fig. 12.2 â&#x20AC;&#x201C; a schematic drawing of a drumlin and a drumlin field.

The water of the ice forms the land. Therefore there also form gorges and other aspects of landscape. There are countlessly more features, which you can see in Fig. 12.3.

Fig.12.3 â&#x20AC;&#x201C; glacial features.

62


The melted ice takes stones and plants to other places. The plants leave their seeds on their new living place and more plants are going to grow there. First, a forest would be in Drenthe and after the ice age a new forest would be in Limburg. Not only is the place of the forest determined by the ice age, also the sort of the trees. The trees in Drenthe were developed to a new sort of tree that can stand the cold ice and snow better than the first trees. This happens with a lot plants and trees, but also with animals. Some species will disappear, others will change to animals that can eat the new plants and can stand the coldness. The ice age changes the landscape and the landscape changes the animals.

Ice Age

Landscape

Animals Fig. 12.4 – a diagram of the ice age, landscape, animal triangle

Conclusion; an ice age changes the landscape drastically. Lakes, seas and falls are formed by all the ice flowing away. But also erratics, gorge and hills are formed by the melting ice flows. An ice age has big impact on the landscape forming. We can’t stop the ice age forming the landscape; it wouldn’t work if we would place fences around the trees so they cannot go away. You can think of all kind of methods, but it will be very, very hard to find one that’s possible. Landscape changes, we can’t stop that, it’s just nature!

63


Sea levels Everything has an end, so of course, an ice age too. When all the ice and snow of the ice age melts, a lot of water will be there. But where does that water has to go? Therefore much land floods and there will be much more water in the seas and oceans too. The sea level rises again. The sea level is a consequence of an ice age, definitely.

Fig. 12.5 – melted ice made place for a small lake at the Austrian ‘glacier’ Pasterze.

But an ice age doesn’t only change the sea level; it also changes the place of rivers and lakes. At some places, there might be more ice and snow on one place than on another. So when it melts, there is more water on some places and that melted ice forms lakes. And some mountains or glaciers are frozen and covered with much ice and snow, which melts down later. That may change the direction of the river on that mountain or glacier (if there already was a river, otherwise a new river will be formed). All the water flowing down the mountains or glaciers into rivers, streams to the sea and there, makes the sea level rise (only a little bit).

64


Continents Will continents be a consequence of ice ages? Well, that could be possible. When there is an ice age, water could freeze up and if itâ&#x20AC;&#x2122;s cold enough, whole oceans or seas can freeze up. That means that lands or continents fuse by ice. Now, different creatures can travel from for example Europe to Africa. So when water freezes up, land bridges will form. This can also happen because the sea levels drop. An example is the Isthmus of Panama (Fig. 12.5), that connected North America with South America and allowed exchange of species. Another example is the former Dogger Bank, in the middle of the North Sea (it connected Great Britain with the Continent).

Fig. 12.6 â&#x20AC;&#x201C; the Isthmus of Panama.

65


Conclusion Just think about how much we depend on the climate and environment, and how we can make and break our world for the best part. Of course, a new ice age is caused by various factors we humans can’t control. Vast amounts of ice can be formed – or melted. It is not only caused by factors out of our reach, but it also has a destructive – or creating – power which is far beyond our capacities. All of this is just because of 2 main factors: insolation and the green/ice house effect. Insolation is very important for earth’s potential warmth. If there is less insolation, there will be less warmth, and vice-versa. The step between insolation and temperature – the atmosphere – is crucial for our protection. Well, as long as we maintain it properly. We contribute for a large part in the production of greenhouse gases; so in fact, we have the climate in our own hands. Unfortunately, we can only guide it, and not change it. We should consider what we do to the climate, which makes us to live our life happy. If every human being would take a moment to realise this, it would help us further. Still one thing is sure; an ice age can barely be prevented, so we can only hope it won’t get that far.

Fig. 13.1 – an artist’s impression on what Earth looked like during the last Glacial.

66


Sources Below is a list of most used sources, and if consulted multiple times, only the homepage is given. crisisboom.com/2011/03/28/nasas-elenin-buzz en.wikipedia.org english.pravda.ru/science/earth/11-01-2009/106922-earth_ice_age-0 ilovecarbondioxide.com images.google.com members.chello.nl/p.wijbrans/home3.htm nl.wikipedia.org paulkiser.wordpress.com/2011/11/14/are-we-missing-an-ice-age-part-i paulkiser.wordpress.com/2011/11/16/are-we-missing-an-ice-age-part-ii-of-iii paulkiser.wordpress.com/2011/11/21/are-we-missing-an-ice-age-part-iii-of-iii www.cotwee.nl/wat-is-cotwee/default.aspx www.exitmundi.nl/sealevel.htm www.falw.vu/~huik/ijstijd.html www.google.com www.google.nl www.indiana.edu/~geol105/images/gaia_chapter_4/milankovitch.htm www.knmi.nl/klimaatverandering_en_broeikaseffect/klimaat_en_klimaatverandering/deel_1.html www.schoolplaten.com www.skepticalscience.com www.theglobalcoolingproject.com www.visionair.nl www.weerstatistieken.nl

We also used the lessons provided, found on: http://issuu.com/pascal.gunsch/docs/module1 http://issuu.com/pascal.gunsch/docs/module2

67


Logbook We split our logbook in several parts. At first, we would like to mention our planning, and how the lessons were planned. Secondly, we want to evaluate several issues, like communication and work.

Lesson Plan September 15th, 2011 − September 29th, 2011 We started the project by watching a movie, ‘The Day after Tomorrow’. During the movie, we had to look for specific items which could be fictitious, and items that could be scientifically right.

October 6th, 2011 We formed our group, called the Science Gang. It includes Pascal, Lotte, Maarten, Selina, Ramona. Maarten also made a stimulating start on the project.

October 13th, 2011 We thought about how we could present our subject. We choose the form of a book, which seemed most convenient in our case, as we had a lot of information to present. We also thought about what subjects we should include and a general layout. We thought of these subjects and divided them: 

meteorological/astronomical/ influences – done by Selina

physical/chemical influences – done by Pascal (+ book)

geographical influences – done by Lotte (+ evaluation)

biological/ecological influences – done by Ramona (+ logbook)

human/economical/industrial influences – done by Maarten

October 27th, 2011 – November 10th, 2011 We presented several subjects provided in our booklet, in our case about reduction of the greenhouse effect. We were not able to work on our project.

November 17th, 2011 – December 23rd, 2011 We set up a working plan. We also took the whos, whats, wheres, whens and hows regarding handing in the subjects into consideration. However, we had to change these later on, due to some problems regarding the date given by the teacher. We worked on the project during class, borrowed laptops, discussed topics, read books and internet pages, etc.

December 24th, 2011 – January 8th, 2012 We worked on the project at home. Lotte worked for 2 days, Selina 4 days, Ramona 3 days, Pascal for 5 days, and Maarten for 0 days. The deadline was set on the 5th of January. Pascal made it to a book.

January 9th, 2012 Pascal put all the information (including Maarten, send that day) into a new book.

68


Evaluation We would also like to evaluate the inputs by our group members regarding several issues like working attitude, communication, keeping deadlines, their work’s quality, etc. We used a scale: + for positive remarks, 0 for neutral remarks, - for negative remarks.

What was his working attitude during class?

Did he communicate and work together?

Pascal: + He worked hard.

Pascal: + He communicated well with everyone

Lotte: 0 She worked during the lessons (not very

and called Maarten, even though the deadline

hard).

had passed.

Maarten: 0 He didn’t always concentrate.

Lotte: + She communicated well with everyone.

Selina: + She did a lot of work during class and

Maarten: + He communicated a lot with Pascal.

she borrowed a laptop every time.

Selina: + She communicated well with

Ramona: 0 She didn’t work very hard during

everyone.

the lessons.

Ramona: + She communicated well with everyone.

What can we say about quantity of his work?

What can we say about quality of his work?

Pascal: + He wrote enough pages (16).

Pascal: + The information is sufficient. He also

Lotte: + She wrote enough pages (10).

put the book (layout, topics, etc.) together.

Maarten: 0 He wrote 9 pages.

Lotte: + The information is sufficient.

Selina: + She wrote enough pages (11)

Maarten: + The information is sufficient.

Ramona: 0 She wrote 7 pages.

Selina: + The information is sufficient. Ramona: + The information is sufficient.

Did he have any problems with the deadline?

What can we say about his end product?

Pascal: + He finished in time.

Pascal: + His overall end product is sufficient.

Lotte: + She finished in time.

Lotte: + She worked according to the planning.

Maarten: 0 He was too late with handing in his

Maarten: + He worked, but needed some

topics (4 days).

stimulation.

Selina: + She finished in time.

Selina: + The end product is sufficient.

Ramona: 0 She was too late with handing in her

Ramona: + The end product is sufficient.

topics (2 days).

69


What is the cause of an ice age? What effects does an ice age have? We answer these questions looking at meteorological, astronomical, physical, chemical, geographical, biological, ecological, human, economical and industrial influences

Pascal Gunsch, Lotte van den Heuvel, Maarten Hoogstad, Selina van Luik, Ramona van Marion. www.iceage.nl.ae

70


Ice Age