Found on every continent and making up more than one fifth of the Earth’s land surface, an arid land area is considered to be “desert” if the annual rain total is less than 10 inches. Deserts are mostly thought of as being hot and dry. However, some are actually cold deserts. Four major types of deserts exist: Hot and dry, semiarid, coastal and cold.
Africa’s Sahara desert is the world’s largest hot and dry desert, and is the home of one of the harshest climates on the planet. Temperatures here may reach 122° F. Parts of the central Sahara desert sometimes get no rain for years at a time. The animals who reside here have adapted over many years to help keep them cool and use less water.
Major deserts of the semiarid variety include the sagebrush of Utah and in Europe, Russia and Northern Asia. The seasons of the semiarid deserts are generally more defined that those found in the hot and dry deserts. The animals of this desert can sometimes be found during the day, although most of them are still nocturnal.
Coastal deserts, including the Atacama of Chile, possess more moderate climates. The maximum annual temperature is around 95°, while the maximum low temperature is somewhere around 25° F. The soil is sandy, and very porous, so any rain water seeps quickly into the ground.
Although we often perceive deserts to have extreme heat, cold deserts actually have snowfall and quite a bit of rainfall. The Takla Makan and Gobi deserts are examples of cold deserts. Some of the animals that are featured in this habitat include jack rabbits, mice and antelope ground squirrels.
Sources:
http://www.mbgnet.net/sets/desert/types.htm
http://www.ucmp.berkeley.edu/glossary/gloss5/biome/deserts.html
http://environment.nationalgeographic.com/environment/habitats/desert-profile/
http://pubs.usgs.gov/gip/deserts/what/
http://www.desertusa.com/desert.html
http://www.worldbiomes.com/biomes_desert.htm