Environmental Tutorial

1. Environmental Tutorial Overpopulation Start Greenhouse Effect Ozone Depletion Acid Rain Deforestation Take the Quiz If possible, place your keyboard aside. You will not need it for this tutorial. Navigate using your mouse.

2. Back Home Hunter/Gathering Societies For much of human history, the population of humans was quite small. Humans relied on hunting prey and gathering plants as a means of survival. The small groups of people would follow the migration patterns of various animals and picked plants along the way. Since they rarely stayed in a single area for long periods of time and food was often unreliable, family groups were small. Imagine if today, the billions of people on Earth still followed the idea of hunting and gathering instead of modern agriculture.

3. Back Home Agriculture Since the development if agriculture thousands of years ago, the human population has greatly increased. Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. This has led to a large increase in the human population as food became more reliable. Currently there are over 7 billion people on Earth. Some would argue that because of the large number of resources that humans consume, the Earth is now overpopulated. Overpopulation is considered the most serious environmental concern our world faces. More people leads to more crime. More use of resources. More war. More pollution.

4. Back Home Overpopulation In the graph above, you can see the estimated world population up to the year 2025. As long as the birth rates around the world exceed the death rates, the human population will continue to increase. Improvements in agriculture, health care, and sanitation has lead to the world population increase. The last time the human population dropped was around 1350, when an estimated 50% of Europe died as a result of bacteria that was carried by fleas. Many environmental problems, such as rising levels of atmospheric carbon dioxide, global warming, and pollution, were increased by the population expansion.

5. Back Home The Greenhouse Effect The Earth and moon are about the same distance from the sun. But the Earth is much warmer. The reason is simple. The Earth has an atmosphere. The Earth’s atmosphere traps heat to warm the planet. The trapping of heat is known as the greenhouse effect. A greenhouse is a glass building used to grow plants year round, even in cold areas. Since glass traps heat, the glass acts like an atmosphere. That’s why science named this warming process on Earth the greenhouse effect. The atmosphere acts like a glass building surrounding the Earth. The heat that is trapped by this natural process warms the planet. That is very good. So why is the greenhouse effect often mentioned as a problem created by humans? average temp = 57°F Average temp = -10°F

6. Back Home The Man-Made Greenhouse Effect CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 Naturally, the greenhouse effect is very good. As mentioned, this process warms the Earth. However, as a result of human actions, the greenhouse effect is out of balance. As technology has progressed, so has our need for energy. That means the burning of fossil fuels (coal, oil, natural gas). When cars, factories, and other man-made devices burn fossil fuels, they release air pollution. A major pollutant released is carbon dioxide (CO2). And this is how the greenhouse effect is out of balance. For centuries, CO2 has been accumulating in the atmosphere. This extra CO2 is trapping excess amounts of heat. The extra heat is causing the Earth to become warmer. The man-made greenhouse effect is known as global warming.

7. Back Home Global Warming Why is Earth much warmer than the moon? Since the Earth has an atmosphere, heat is trapped. Because air pollutants such as CO2 are accumulating in the atmosphere, the atmosphere is getting thicker. This means that extra heat is trapped. The fear is this could alter climate patterns around the world. This makes agriculture very difficult since climate affects how plants grow. If agriculture was disrupted, how would that affect the human population? correct Earth is much closer to the sun Earth has been struck by numerous meteors Earth has an atmosphere Try again Try again The human population would increase. Probably not The human population would decrease. correct The human population would remain unchanged. Probably not

8. Back Home Global Warming Solutions There is no one easy solution to global warming. Since our society demands so much energy, fossils fuels are the best way to provide the energy because of the lower cost. However, there are steps that everyone can take to help reduce the use of fossil fuels in their lives. The following steps help reduce the usage of fossil fuels. Recycling helps to save natural resources. Using energy efficient products at home reduces pollution. Turn up the air conditioning a few degrees in the summer. Or simply open the windows. Turning off electronic products when not in use. Carpooling. Walking short distances. Biking longer distances. 78°F (or warmer) is recommended in the summer to save electricity. Every little bit helps. Buy products with the “Energy Star” label. They require less energy to operate. Incandescent light bulbs get hot, which is wasted energy. Stop using them. Fluorescent light bulbs waste less energy and last longer. Buy them. Don’t be lazy. Turn off that computer when not in use.

9. Back Home The Ozone Layer UV UV UV Did you know? Before the ozone layer existed, all life on Earth lived under water. High up in the stratosphere is an area called the ozone layer. The ozone layer protects life on the surface of the Earth because the ozone layer absorbs harmful ultraviolet (UV) radiation from the sun. Since the UV radiation is absorbed high in the sky, the UV never reaches the ground where people, plants, and other animals live. This is good. Ozone layer prevents UV radiation from striking the Earth’s surface

10. Back Home So what’s the problem? UV UV UV UV UV UV Human activity of course. Chlorofluorocarbons (CFC’s) are man-made chemicals used in refrigerators, aerosols, and solvents. These CFC’s are released into the air and drift up to the ozone layer. Ozone layer prevents UV radiation from striking the Earth’s surface Thinner ozone layer blocks less UV radiation Sadly, CFC molecules react with ozone molecules. As a result, the ozone molecules are broken apart and thus can no longer absorb as much UV radiation. This allows more UV radiation to reach the surface. CFC CFC CFC CFC CFC CFC

11. UV Back Home Effects of UV radiation UV radiation breaks apart DNA molecules UV radiation is a known mutagen, which means it causes DNA mutations. Due to this fact, UV radiation is harmful to all life on Earth, not just humans. The following is a partial list of problems caused by excess UV radiation from the sun. Skin cancer around the world has greatly increased. Crops do not grow as well. Keep in mind the world population is increasing. Cataracts and other eye problems are rising. Destruction of plankton, which is the basis of ocean food webs.

12. Back Home How to lessen your exposure? Sunburn is the most obvious sign of too much sun. Too much sun triggers the growth of cancerous cells. There are easy steps you can take to help reduce your exposure to the sun. Proper clothing like hats, long sleeves, and sunglasses help to block UV radiation. Use a sunscreen of at least SPF-30 when you plan to spend some time outside.

13. Back Home Stop the CFC Madness In the mid-1980’s, scientists were shocked to discover a hole in the ozone layer over Antarctica. Luckily Antarctica is uninhabited by people, but around the rest of the world the ozone layer was getting thinner also. So more UV radiation was striking the surface of Earth. Nations around the world saw this as a problem, and took action. Over 150 nations signed the Montreal Protocol and agreed to reduce the use of CFCs. The Montreal protocol is considered one of the most successful treaties in history. Antarctica

14. Back Home Ozone Outlook Since CFC’s can stay harmful for about 100 years, the pollution we released in the 1970’s will be in the atmosphere for some time. But since the Montreal Protocol, CFC usage has been greatly reduced. This has allowed the ozone layer to naturally repair itself, but the final recovery of the ozone layer is expected to take several lifetimes. But we are on the right track.

15. Back Home Acid Rain What goes up….must come down. We’ve all heard this expression and it is very fitting concerning this next topic, acid rain. Normally, rainfall is life sustaining as rain provides much needed water. But what if the rain water is polluted? Examine the pH scale above. Notice that chemicals less than 7 are considered acids. Naturally, rain water is slightly acidic (pH of 5.6) due to chemicals commonly found in the air. These chemicals get washed down with the rain and cause rain to be slightly acidic. This is natural. So what is acid rain?

16. Back Home What goes up? Once again, humans and fossil fuels are the cause of this problem. When fossil fuels are burned in cars and factories, they release sulfur dioxide and nitrogen oxides into the air. Keep in mind that millions of cars and thousands of factories are releasing these pollutants every day. NOx SO2

17. Back Home Must come down… sulfuric acid Nitric acid Now that the sulfur dioxide and nitrogen oxides are in the air, they combine with water in the air to form two acids…sulfuric acid and nitric acid. When it eventually rains, these acids will fall down and run into rivers, lakes, and streams. So even though rain is naturally acidic, these chemicals make rain super acidic (pH of 3-4).

18. Back Home Damages from acid rain As rivers, lakes, and streams collect more acids, the water becomes more deadly. The acidic water has been blamed for frog deformities and can be deadly to fish, frogs, and other aquatic life. The sulfur and nitrogen in acid rain is harmful to human lungs and can lead to asthma or bronchitis. The acids in the soil can be absorbed through the roots of plants and trees and harm their growth. Acids can peel paint or wear down stone statues.

19. Back Home Acid Rain Solutions Avoid staring inside the fridge for long amounts of time Since the burning of fossil fuels is the cause of acid rain, the obvious solution is to reduce the use of fossil fuels. While this may be easier said than done, there are alternative energies that are less polluting. Many government programs exist to help consumers go solar at home. Encourage your parents to look into this great alternative. Saving electricity at home reduces the amount of fossil fuels that are burned. Please help by turning off electronics when they aren’t being used. Here are a few more ideas to try at home. Be sure to share them with your folks. Wash full laundry loads Turn off the TV when not in use Open the blinds during the day and turn off the lights Change the furnace filter once a year Dry wet clothes outside on a laundry line

20. Back Home Deforestation As stated earlier, human overpopulation is the cause for many problems. Another such problem is called deforestation. Like the name implies, this is the clearing of forested land. Once cleared, the cleared land is often used to build housing or is converted into farmland to grow crops. As cities expand further and further into once wilderness areas, the animals living in these areas will be displaced. The plant-life is obviously destroyed as the land is cleared. Around the world, there is a high demand for wood products. Wood is used as fuel, building supplies, and paper. So in order to meet the demand around the world, trees are cut down and sold as lumber. Paper rolls Lumber for building Many poor nations still burn wood to cook and heat their homes

21. Back Home Why is deforestation harmful? Hopefully this is obvious. By destroying the habitats of wildlife this causes extinctions. Lets not forget that the vast majority of drugs used to treat illness come from chemicals found in plants and animals. So by causing the extinction of wildlife, we are losing an important tool to help fight disease. As humans move into areas that were once wilderness, animal attacks are on the rise. Food chains and food webs become out of balance. Examine the food web above. What would probably happen to these organisms if the trees were destroyed and cut down? Probably not since the main food source is gone. They would continue to survive just fine The rest may go extinct since there are no producers left correct

22. Back Home How to help prevent Deforestation? I’m sure you know some ways to help reduce the use of wood products. Recycle…recycle…recycle! When possible, look into purchasing 2nd hand furniture. Often, older furniture is even built to better standards and will last longer. Try and go paperless at home. Sign up for e-bills. Remove your name from “junk mail” distributors. Speak out to your local and federal representatives. They can help to create new laws to protect the environment. Support various environmental action groups such as GreenPeace or the Sierra Club.

23. Back Home Conclusion So it is clear that many environmental problems exist today. It is also clear the human activity is the leading cause. Humans are releasing the pollution that causes the ozone problem, acid rain, and global warming. Human actions are behind deforestation. So now is the time to act. It starts with local action and changes at home. Spread the word to your family members about ways to help lessen the impact that humans have on the environment. Education is the key to reversing this trend and it starts with you.

24. Back Home Quick Quiz #1 Correct Coal is a fossil fuel. Which is not a fossil fuel? Coal Wood Natural gas Oil Natural gas is a fossil fuel. Oil is a fossil fuel.

25. Back Home Quick Quiz #2 Try again Which climate altering gas is released from the burning of fossil fuels? Nitrogen oxide CFC’s Try again Carbon dioxide Sulfur oxide Correct Try again

26. Back Home Quick Quiz #3 Try again Which man-made molecule is responsible for the destruction of the ozone layer? Nitrogen oxide CFC’s Correct Carbon dioxide Sulfur oxide Try again Try again

27. Back Home Quick Quiz #4 This is due to acid rain What is happening as a result of the thinning of the ozone layer? Rivers and lakes are more acidic The Earth is warming This is due to burning fossil fuels Forests are being cleared More UV radiation is striking Earth This is due to our need for wood Correct

28. Back Home Quick Quiz #5 This is bad… but what’s causing it? What is considered to be the most serious environmental threat? Global warming Ozone layer destruction This is bad… but what’s causing it? Acid rain Overpopulation This is bad… but what’s causing it? Correct

29. Back Home Quick Quiz #6 Try again The pollutants that lead to acid rain come from which? Increase in Earth’s temperature Fossil fuel burning Correct The use of aerosol can sprays Extra amounts of UV radiation Try again Try again

30. Back Home Quick Quiz #7 Correct Which is an immediate threat to the habitat of living organisms? Deforestation Greenhouse effect Try again Acid rain Ozone depletion Correct. There is another answer too. Find it. Try again

31. Back Home Quick Quiz #8 Try again Sulfur dioxide and nitrogen oxide are related to which problem? Ozone destruction Deforestation Try again Acid rain Global warming Correct Try again

32. Back Home Quick Quiz #9 True, but there is a better answer. Recycling and saving resources is a way to help which? Ozone destruction Greenhouse effect True, but there is a better answer. Acid Rain All of these True, but there is a better answer. Correct

33. Back Home Quick Quiz #10 Correct The Montreal Protocol helped to reduce the amount of which? CFCs used In industry Acids released into lakes Try again Wood cutting Carbon dioxide in the air Try again Try again

34. Back Home Be sure to turn in your worksheet when finished.