SOLVED

11) Which one of the following is the one best measure of the wetness or dryness of a region? A) total annual precipitation B) mean annual temperature C) difference between annual precipitation and evaporation potential D) percentage of precipitation that falls during the summer months 12) Which one of the following concerning desert lands is false? A) Less than 30 percent is covered with dunes and drifting sand. B) Wind erosion and deposition are important processes. C) Running water has little effect on shaping the landscape. D) Most desert areas are characterized by descending wind patterns. 13) Desertification has been particularly well documented over the past 50 years in ________. A) the Empty Quarter of the Arabian Peninsula B) the Sahel along the southern margin of the Sahara Desert C) the Dust Bowl states of the Great Plains D) the steppe lands of southern Russia, Ukraine, and Kazakhstan 14) All of the following statements concerning dry lands are true except ________. A) precipitation totals are low; dew points are lower in the summer than winter B) evaporation potential exceeds actual precipitation C) storms are infrequent and rainfall amounts are highly variable D) wind is the dominant agent of erosion and sediment transport 15) How are sand grains transported by the wind? A) high in the moving air column as suspended load B) by saltation in the first few meters above the land surface C) by deflation of abraded desert pavement D) by being picked up in swirling dust clouds and carried to distant blowouts 16) Which of the following best describes the climatic factors that cause low latitude deserts like the Sahara in Africa? A) Cool, dry air aloft is descending; surface winds are blowing toward the equator. B) Warm, humid air aloft is descending; surface winds blow away from the equator. C) Warm, humid air is rising; surface winds are calm. D) Cool, dry air at the surface is rising causing winds to blow away from the equator. 17) How is desert pavement formed? A) Deflation and sheet wash remove fine-sized materials leaving coarse, weathered, rock fragments concentrated at the surface. B) Blowing wind removes fine-size soil particles; coarser particles abrades to sand size. C) Running water deposits gravel and sand over the finer-sized soil particles. D) Intense chemical weathering removes the sand- and silt-sized particles, leaving coarse rock debris covering the land surface. 18) Loess deposits in the central United States ________. A) blew in from the dry areas in the Great Plains and southwestern desert areas B) originated as rock flour in Pleistocene glacial streams and rivers C) accumulated from flooding of the Mississippi River D) were originally deposited as barchanoid dunes and later redeposited by glaciers 19) Assume that the central slip face of a barchan dune slopes downhill toward the east. What is the direction of the prevailing wind? A) east to west B) north to south C) south to north D) west to east 20) Desert and steppe lands cover about what percentage of Earth’s land area? A) 10% B) 66% C) 30% D) 3%