Deserts
About Deserts
What exactly is a desert?
A desert is defined as an area of land that receives no more than 25 centimeters (roughly 10 inches) of precipitation a year. It is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the land surface of the Earth is arid or semi-arid.
What are the characteristics of a desert?
low and irregular patterns of precipitation (aridity), frequently resulting in drought during summer months
prolonged high temperatures: both air and soil
high evaporation rates from soil surfaces
extreme temperature fluctuations
What are the types of deserts?
Sub-tropical deserts (hot and dry year round)
Coastal deserts (cool winters and warm summers)
Cold Winter deserts (long dry summers, low rainfall winters)
Polar deserts (cold year round)
How do deserts form?
Deserts are hot because of the low specific heat capacity of sand and rock. Deserts are formed as a result of high pressure zones, continentality, coastal cooling and rain shadow areas.