Principal Deserts of the World

Principal Deserts of the World

Deserts are arid regions, generally receiving less than ten inches of precipitation a year, or regions where the potential evaporation rate is twice as great as the precipitation. The world's deserts are divided into four categories. Subtropical deserts are the hottest, with parched terrain and rapid evaporation. Although cool coastal deserts are located within the same latitudes as subtropical deserts, the average temperature is much cooler because of frigid offshore ocean currents. Cold winter deserts are marked by stark temperature differences from season to season, ranging from 100° F (38° C) in the summer to 10° F (–12° C) in the winter. Polar regions are also considered to be deserts because nearly all moisture in these areas is locked up in the form of ice.

Desert Location Size Topography SUBTROPICAL DESERTS Sahara Morocco, Western Sahara, Algeria, Tunisia, Libya, Egypt, Mauritania, Mali, Niger, Chad, Ethiopia, Eritrea, Somalia 3.5 million sq. mi. 70% gravel plains, sand, and dunes. Contrary to popular belief, the desert is only 30% sand. The world's largest nonpolar desert gets its name from the Arabic word Sahra', meaning desert Arabian Saudi Arabia, Kuwait, Qatar, United Arab Emirates, Oman, Yemen 1 million sq. mi. Gravel plains, rocky highlands; one-fourth is the Rub al-Khali (“Empty Quarter”), the world's largest expanse of unbroken sand Kalahari Botswana, South Africa, Namibia 220,000 sq. mi. Sand sheets, longitudinal dunes Australian Desert        Gibson Australia (southern portion of the Western Desert) 120,000 sq. mi. Sandhills, gravel, grass. These three regions of desert are collectively referred to as the Great Western Desert—otherwise known as “the Outback.” Contains Ayers Rock, or Uluru, one of the world's largest monoliths  Great Sandy Australia (northern portion of the Western Desert) 150,000 sq. mi.  Great Victoria Australia (southernmost portion of the Western Desert) 250,000 sq. mi.  Simpson and   Sturt Stony Australia (eastern half of the continent) 56,000 sq. mi. Simpson's straight, parallel sand dunes are the longest in the world—up to 125 mi. Encompasses the Stewart Stony Desert, named for the Australian explorer Mojave U.S.: Arizona, Colorado, Nevada, Utah, California 54,000 sq. mi. Mountain chains, dry alkaline lake beds, calcium carbonate dunes Sonoran U.S.: Arizona, California; Mexico 120,000 sq. mi. Basins and plains bordered by mountain ridges; home to the Saguaro cactus Chihuahuan Mexico; southwestern U.S. 175,000 sq. mi. Shrub desert; largest in North America Thar India, Pakistan 175,000 sq. mi. Rocky sand and sand dunes COOL COASTAL DESERTS Namib Angola, Namibia, South Africa 13,000 sq. mi. Gravel plains Atacama Chile 54,000 sq. mi. Salt basins, sand, lava; world's driest desert COLD WINTER DESERTS Great Basin U.S.: Nevada, Oregon, Utah 190,000 sq. mi. Mountain ridges, valleys, 1% sand dunes Colorado Plateau U.S.: Arizona, Colorado, New Mexico, Utah, Wyoming 130,000 sq. mi. Sedimentary rock, mesas, and plateaus—includes the Grand Canyon and is also called the “Painted Desert” because of the spectacular colors in its rocks and canyons Patagonian Argentina 260,000 sq. mi. Gravel plains, plateaus, basalt sheets Kara-Kum Uzbekistan, Turkmenistan 135,000 sq. mi. 90% gray layered sand—name means “black sand” Kyzyl-Kum Uzbekistan, Turkmenistan, Kazakhstan 115,000 sq. mi. Sands, rock—name means “red sand” Iranian Iran 100,000 sq. mi. Salt, gravel, rock Taklamakan China 105,000 sq. mi. Sand, dunes, gravel Gobi China, Mongolia 500,000 sq. mi. Stony, sandy soil, steppes (dry grasslands) POLAR Arctic U.S., Canada, Greenland, Iceland, Norway, Sweden, Finland, Russia 5.4 million sq. mi. Snow, glaciers, tundra Antarctic Antarctica 5.5 million sq. mi. Ice, snow, bedrock

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