1. When did the Medieval Warm Period occur? When did the Little Ice Age occur? What impacts on human societies did they have?

2. What is the difference between weather and climate?

3. How is climate defined?

4. Compare the definitions of weather and climate. Is one day of record heat an example of weather or climate? What about one warmer-than-average year? A decade of warmer-than-average years?

5. Besides the atmosphere, what are the other parts of the climate system?

6. What happened to temperatures in the Northern Hemisphere during the Younger Dryas?

7. By how much has the average temperature of the lower atmosphere increased over the last 100 years?

8. Is the temperature increase over the last 100 years an example of weather or climate change? Explain.

9. If a severe storm strikes, can scientists definitely say it was caused by climate change? Explain.

10. What are climate forcing factors? How are they different from climate feedbacks? Give examples of each.

11. Explain how ice cover at high latitudes can function as a positive feedback that destabilizes climate or as a negative feedback that stabilizes climate.

12. What caused the Cenozoic cooling trend?

13. Describe the Quaternary ice age in terms of its timing and repeated climate cycles. Describe the climate of the Holocene epoch.

14. What are Milankovitch cycles? With what kind of climate change pattern are they associated?

15. What are glacials and interglacials? About how long, on average, has each lasted during the last million years? What caused them, climate forcing or climate feedbacks?

16. Provide an example of a climate anomaly. Do climate forcings or climate feedbacks cause anomalies?

17. What natural archives do paleoclimatologists examine to reconstruct ancient climates and environments?

18. Where is most carbon on Earth stored? How does carbon enter and leave this long-term storage?

19. Compare and contrast the long-term carbon cycle with the short-term carbon cycle. Explain how carbon moves within each.

20. What two main types of human activity are transferring carbon to the atmosphere? How many billion metric tons are transferred to the atmosphere each year?

21. What is the current rate of increase of CO₂ concentrations in the atmosphere each year in parts per million?

22. What is the Keeling curve? What does it show?

23. How do we know what prehistoric CO₂ concentrations were? Compare current CO₂ concentrations in the atmosphere with those over the last 800,000 years.

24. What concentration (in ppm) did natural atmospheric CO₂ not exceed over the last 800,000 years?

25. What is the current atmospheric CO₂ concentration (in ppm)? Where is this “extra” carbon coming from?

26. Describe the relationship between CO₂ and global atmospheric temperature.

27. Geographically, where is most of the current warming trend happening? Why is it happening there?

28. Are there any natural climate forcing factors that can explain the current warming trend?

29. What are some of the responses of Earth’s physical systems to the current warming trend? What changes in Earth’s physical systems are anticipated in this century?

30. What is a climate model? Why do climate models make such a wide range of climate projections?

31. What actions must be taken to address the problem of climate change?

32. To avoid significant climate change, what is the atmospheric CO₂ concentration that most scientists think must not be exceeded?

33. By what percentage should global anthropogenic CO₂ emissions be cut to achieve that concentration?

34. How, specifically, can individuals reduce their CO₂ emissions?

35. Give an example of how a single individual is linked to Earth’s climate system.