Ch. 13 Answer Key

1. What is a glacier?
D. A large, long-lasting river of ice
2. The smallest type of glacier is a(n):
E. Valley glacier.
3. Ice within a glacier is:
A. Perpetually moving forward toward the terminus.
4. A moraine is:
A. A deposit of till that was in contact with glacial ice.
5. Which glacial landforms will be left by a retreating continental ice sheet? (Choose all that are true.)
A. Drumlins, eskers, and terminal moraines
B. Ground moraine, kettle lakes, end moraines
C. Deposits of till, outwash plain, glacial erratic
6. In response to global warming, alpine glaciers around the world are:
A.Generally retreating.
7. Retreat of Arctic sea ice:
E. Will change albedo and be a positive feedback to warming.
8. Oxygen isotopes provide a climate proxy because:
B. Oxygen isotopes are sensitive to temperature, evaporation, and precipitation.
9. Which of the following statements about orbital parameters are true? (Choose all that apply.)
B. They include precession, obliquity, and axial tilt.
C. They produce climate cycles with a 100,000-year periodicity.
D. They correlate with observations of paleoclimate.
E. They do not influence global climate.
10. Climate feedbacks:
A. May magnify or suppress the influence of orbital parameters.
11. For a glacier to advance:
D. Accumulation must exceed wastage.
12. Rapid climate changes:
C. Are caused by climate feedbacks, not by orbital parameters.