Work through the following questions to test your knowledge of climate feedback loops. Refer back to the lesson pages and learning tools as needed.

1. Define positive feedback. Define negative feedback.
2. What are the similarities between positive and negative feedback? What are the differences?
3. Give an example of both a positive and negative feedback loop that have not been described in the lesson.
4. What is the "set point" on a thermostat? How is this idea important to feedback cycles?

5. What processes of the carbon cycle allow carbon dioxide to act as a climate thermostat?
6. In what ways are the buffering abilities of carbon sinks being reduced by climate change?
7. Does the fertilization effect result in a positive or negative feedback loop in how it affects atmospheric carbon dioxide emissions? Draw a diagram of this feedback cycle.
8. Challenge: How might absorption of carbon dioxide by the ocean have a negative impact on the ocean? Use outside sources if necessary.

9. Draw a feedback loop describing the effect of climate change on permafrost. Include all possible sources of emissions you learned about in this lesson (remember- methane clathrate hydrates are also found within the permafrost.)
10. In what location are stores of clathrate hydrates stabilized by climate change? Why are they stabilized?
11. In what location are stores of clathrate hydrates destabilized by climate change? Why are they destabilized?
12. Challenge: Create a large feedback loop summarizing the feedback effects of climate change in the Arctic. You will need to use multiple, interconnected loops.

13. Which greenhouse gas is responsible for the majority of earth's greenhouse warming?
14. Describe the feedback loop involving water vapour and temperature. Is it positive or negative?
15. Describe the feedback loop involving Arctic snow and ice cover, albedo and temperature. Is it positive or negative?
16. How do clouds affect earth's temperature? Describe one way that clouds could be involved in a negative feedback cycle and one way in which they could be involved in a positive feedback cycle.

17. Name two consequences of our changing climate that have supported the outbreak of mountain pine beetle.
18. Describe how the outbreak of mountain pine beetle affects climate.
19. Challenge: Describe an ecosystem feedback loop other than the mountain pine beetle.