Deserts are found across our planet along two fringes parallel to the equator at 25–35° latitude in both the northern and southern hemispheres. Deserts are arid or dry regions and receive less than 10 inches of rain per year. Biologically, they contain plants and animals adapted for survival in arid environments. Physically they are large areas with a lot of bare soil and low vegetation cover. The world’s deserts occupy almost one-quarter of the earth’s land surface, which is approximately 20.9 million square miles.
© Byron Hukee
The Mojave Desert is so diverse that it is subdivided into five regions: northern, south-western, central, south-central, and eastern. Elevations range from below sea level at Death Valley National Park to 2.26 miles on Mt. Charleston in the Spring Range of Nevada.
Deserts receive little rainfall, however, when rain does fall, the desert experiences a short period of great abundance. Plants and animals have developed very specific adaptations to make use of these infrequent short periods of great abundance.
Deserts landscapes are more diverse than many expect. Some are found on a flat shield of ancient crystalline rocks hardened over many millions of years, yielding flat deserts of rock and sand such as the Sahara. Others are the folded product of more recent tectonic movements, and have evolved into crumpled landscapes of rocky mountains emerging from lowland sedimentary plains, as in Central Asia or North America .