1. The second layer of the atmosphere up from Earth, where the ozone layer is that protects us from harmful UV rays, is the

2. What is climate change?

3. Which human activity contributes the most carbon dioxide to the atmosphere?

4. Generally, the farther a place is from the equator, the warmer its climate will be.

5. Which is not a factor that affects climate?

6. Which season is shown in the northern hemisphere?

7. Which season is shown in the southern hemisphere?

8. Which provides clues to the climate of the distant past

9. Which is a natural source of greenhouse gases?

10. What do greenhouse gases do?