Answer Key Fixing the Ozone Hole
1. Why is it good to have ozone high up in the atmosphere, but bad to have it near the earth\'s surface?
Answer: When ozone is high in the atmosphere, it shields the earth from UV radiation that causes sunburns and skin cancer, and may harm plant and animal life. When ozone is at the earth\'s surface where humans can breathe it, it is dangerous for our health.
2. What does Dr. Newman mean when he says that ozone is the earth's sunscreen?
Answer: The ozone layer screens the sun's UV radiation from reaching the surface of the earth, just like sunscreen keeps the sun's UV radiation and from burning our skin.
3. If countries stopped using CFCs back in 1979, why is the ozone layer still so thin?
Answer: It takes 50 years for CFCs to reach the stratosphere, where the ozone layer is. The CFCs released into the atmosphere in the 1970s are still reaching the stratosphere today. Air pollution today is also making it harder for the ozone layer to repair itself.
4. What might have happened if countries had decided to keep using CFCs instead of banning them?
Answer: These chemicals would have continued to slowly eat away at the ozone layer, and it would keep getting thinner. There would be less plankton, so there would be fewer fish in the ocean. There would also be more diseases like skin cancer.
5. The Aura satellite measures chemicals in the atmosphere and the amount of UV radiation that reaches the earth's surface. What do these measurements have to do with the level of ozone in the atmosphere?
Answer: More chemicals mean more ozone is being destroyed. More UV radiation reaching the earth's surface means there is less ozone in the atmosphere protecting the earth.
6. What is the relationship between the temperature in the Antarctic and the size of the ozone hole?
Answer: When the temperatures drop to their lowest levels, more ozone is destroyed, so the hole gets larger. Once it warms up, ozone levels begin to increase as less ozone is destroyed.
7. Which of the suggestions for reducing air pollution would be the easiest for you to do? Explain.
Answer: Answers will vary, but all kids can do their part to reduce pollution in some way.
 

Study Questions Fixing the Ozone Hole
1. Why is it good to have ozone high up in the atmosphere, but bad to have it near the earth\'s surface?



2. What does Dr. Newman mean when he says that ozone is the earth's sunscreen?



3. If countries stopped using CFCs back in 1979, why is the ozone layer still so thin?



4. What might have happened if countries had decided to keep using CFCs instead of banning them?



5. The Aura satellite measures chemicals in the atmosphere and the amount of UV radiation that reaches the earth's surface. What do these measurements have to do with the level of ozone in the atmosphere?



6. What is the relationship between the temperature in the Antarctic and the size of the ozone hole?



7. Which of the suggestions for reducing air pollution would be the easiest for you to do? Explain.



 

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