Earth Systems & Resources unit test
A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.
Upwelling
Thermohaline circulation
Cone of depression
Divergent, convergent and transform boundaries
Albedo
Soil formation factors
Soil permeability and porosity
Watershed
Cation exchange capacity
Watershed divide
What each soil horizon holds
Aquifer and water table
Short answer 1. Define or explain: Subduction and volcanic arcs
3 ptsShort answer 2. Define or explain: El Niño and La Niña
3 ptsShort answer 3. Define or explain: Soil erosion causes
3 ptsShort answer 4. Define or explain: Saltwater intrusion
3 ptsFree response
10 ptsThis course has no free-response prompt tagged to this unit, so one from elsewhere in the course is used. It is still worth writing — the skill transfers.
ANALYZE AN ENVIRONMENTAL PROBLEM USING MODELS. Examine the model, described below. THE GREENHOUSE EFFECT AND EARTH'S ENERGY BUDGET. A diagram shows incoming shortwave solar radiation arriving at the top of the atmosphere. Of that incoming energy, about 30 percent is reflected back to space by clouds, atmospheric particles, and bright surfaces such as ice and desert; this fraction is labeled albedo. The remaining roughly 70 percent is absorbed by the atmosphere, the land, and the oceans. The warmed surface emits longwave infrared radiation upward. Arrows show a portion of that outgoing longwave radiation being absorbed by greenhouse gas molecules in the atmosphere — carbon dioxide, methane, water vapor, and nitrous oxide are labeled — and re-emitted in all directions, with a share returning downward to the surface. A caption notes that at equilibrium, energy leaving the top of the atmosphere equals energy arriving, and that increasing the concentration of greenhouse gases increases the fraction of outgoing longwave radiation intercepted.
A(i). Identify the form of radiation Earth’s surface emits. A(ii). Identify one greenhouse gas shown in the model that is produced by both natural and human activity.
B. Explain why greenhouse gases absorb outgoing longwave radiation but not incoming shortwave radiation.
C. Explain how melting Arctic sea ice creates a positive feedback loop, using the concept of albedo from the model.
D. Describe one human activity that increases the concentration of methane in the atmosphere, and explain why methane is of concern despite being present at much lower concentrations than carbon dioxide.
E. Explain why the removal of an equal mass of carbon dioxide and methane from the atmosphere would not have equal effects on radiative forcing over a century.
F. Describe one strategy for reducing atmospheric greenhouse gas concentrations, and explain one limitation of that strategy.