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30 terms

Geo 12

STUDY
PLAY
Deposition of glacial rock flour from blowing winds is responsible for ________.
loess deposits
A playa is an intermittent lake on the floor of a desert valley.
true
________ dunes are long, high, sand dunes parallel with the prevailing wind direction.
Longitudinal
A ________ is an intermittent stream channel in the dry land areas of the western United States.
wash
a dune migrates in the direction of inclination of the slip face
true
Which of the following best describes the climatic factors that cause low latitude deserts like the Sahara in Africa?
cool, dry air aloft is descending; surface winds are blowing toward the equator
________ have rainfall amounts and soil moisture contents between those of true deserts and humid lands.
Steppes
Despite infrequent rainfalls, erosional and depositional forces are important in desert landscapes
true
What mature, desert landscape feature consists of coalesced alluvial fans?
bajada
The loess in western China was derived from windblown, glacial rock flour
false
________ dunes result from persistent, onshore winds in certain coastal areas.
parabolic
In which area would surface water most effectively infiltrate into the local groundwater system?
streams flowing in the numerous channels of an alluvial fan
Blowouts are broad, shallow depressions excavated by deflation
true
What will effectively limit further deflation in a given area?
desert pavement
A ________ is formed by abrasion of rocks by windblown sand.
ventifact
Deserts between 30 and 45 degrees of latitude are more extensive in the southern hemisphere than in the northern hemisphere.
false
Inselbergs are ________.
bedrock hills in a highly eroded desert landscape
What transports sand in running water and blowing winds?
saltation
What are intermittent streams in the United States called?
washes
________ refers to the "bouncing" mode of sand transport in a windstorm or stream.
saltation
Loess consists mainly of silt-sized particles.
true
About one-third of the Earth's land areas have arid to semiarid climates.
true
A ________ is a crescent-shaped dune whose tips point downwind.
barchan
Most dry lands lie between ________ degrees north and south of the equator.
20 and 30
Sand dunes cover more than 50 percent of most desert lands.
false
Desert and steppe lands cover about what percentage of Earth's land area?
30%
What is a low-latitude desert characterized by high atmospheric pressures and descending air masses
Sahara Desert; northern Africa
Wind turbines 10 meters above the ground surface are subjected to relatively little abrasion by blowing sand.
true
What is determined by the angle of repose for dry sand?
inclination angle of a dune slip face
What is the one best measure of the wetness or dryness of a region?
difference between annual precipitation and evaporation potential