Base map by NOAA. Sand dunes in the Sahara Desert of Libya: Most people think of deserts as "sandy" landscapes. That is true part of the time. A desert is a landscape or region that receives very little precipitation - less than mm per year about ten inches. There are four different types of deserts based upon their geographic situation: 1 polar deserts, 2 subtropical deserts, 3 cold winter deserts, and 4 cool coastal deserts.
As shown on the map above, deserts occur on all of Earth's continents. The two largest deserts on Earth are in the polar areas. The Antarctic Polar Desert covers the continent of Antarctica and has a size of about 5. The second-largest desert is the Arctic Polar Desert. It has a surface area of about 5.
The Canada Glacier is in the background. The rest of Earth's deserts are outside of the polar areas. The largest is the Sahara Desert, a subtropical desert in northern Africa.
It covers a surface area of about 3. A list of more than twenty of the largest non-polar deserts can be found below. When most people think of a desert, they imagine a landscape covered with sand and sand dunes. An oasis in the Arabian desert, surrounded by sand dunes. The Arabian Desert is the fifth-largest desert in the world and the largest in Eurasia.
It is located in far Western Eurasia, in the Arabian Peninsula. At the center of the Arabian Desert in Saudi Arabia, is one of the largest continuous bodies of sand in the world, complete with picture-postcard sand dunes. Despite being a desert, the Gobi is famed for its rare animals such as snow leopards and Bactrian camels.
Sunset over a rock formation in the Kalahari Desert in South Africa. The Kalahari Desert is the seventh largest desert in the world. Simply, its name reflects the natural aspect of the region. The Patagonian Desert or the Patagonian Steppe is the eighth largest desert in the world, and the largest desert in South America.
This entire region is a cold desert scrub steppe, made up of rocky shrubland and thorn thicket and experiencing year-round frosts and constant winds. Despite this, Patagonia is home to an array of wildlife including foxes, llamas, armadillos, and more. Sweeping sand and rock formations in the Syrian Desert. The Syrian Desert or the Syrian Steppe is a subtropical desert that is the ninth largest desert in the world.
The southern part of the Syrian Desert merges with the larger Arabian Desert. The surface of the desert is bare and rocky, and contains scattered wadis or dry riverbeds. Along with its natural uniqueness, the desert is also famous for the Great Basin National Park , located in the central part of the desert.
This certainly applies in regions that are subject to "desertification", where increasing temperatures i. Deserts are often some of the hottest and most inhospitable places on Earth, as exemplified by the Sahara Desert in Africa, the Gobi desert in northern China and Mongolia, and Death Valley in California.
But they can also be cold, windswept landscapes where little to no snow ever falls — like in the Antarctic and Arctic. So in the end, being hot has little to do with it. In fact, it would be more accurate to say that deserts are characterized by little to no moisture and extremes in temperature.
All told, deserts make up one-third of the surface of the Earth. But most of that is found in the polar regions. In terms of sheer size, the Antarctic Desert is the largest desert on Earth, measuring a total of Antarctica is the coldest, windiest, and most isolated continent on Earth, and is considered a desert because its annual precipitation can be less than 51 mm in the interior.
There are no permanent human residents, but anywhere from 1, to 5, researchers inhabit the research stations scattered across the continent — the largest being McMurdo Station, located on the tip of Ross Island. Beyond a limited range of mammals, only certain cold-adapted species of mites, algaes, and tundra vegetation can survive there.
Despite having very little precipitation, Antarctica still experiences massive windstorms. Much like sandstorms in the desert, the high winds pick up snow and turn into blizzards. These storms can reach speeds of up to km an hour mph and are one of the reasons the continent is so cold. In fact, the coldest temperature ever recorded was taken at the Soviet Vostok Station on the Antarctic Plateau. Using ground-based measurements, the temperature reached a historic low of Analysis of satellite data indicated a probable temperature of around However, this reading was not confirmed.
Interestingly, the second-largest desert in the world is also notoriously cold — The Arctic Desert. Located above 75 degrees north latitude, the Arctic Desert covers a total area of about Here, the total amount of precipitation is below mm 10 inches , which is predominantly in the form of snow. But perhaps the most interesting aspect of the Arctic Desert is its sunshine patterns.
During the summer months, the sun doesn't set for a period of 60 days. These are then followed in the winter by a period of prolonged darkness. The third largest desert in the world is the more familiar Sahara, with a total size of 9. The average annual rainfall ranges from very low in the northern and southern fringes of the desert to nearly non-existent over the central and the eastern part.
All told, most of the Saraha receives less than mm 0. However, in northern fringe of the desert, low pressure systems from the Mediterranean Sea result in an annual rainfall of between to mm 3.
The southern fringe of the desert — which extends from coastal Mauritania to the Sudan and Eritrea — receives the same amount of rainfall from the south.
The central core of the desert, which is extremely arid, experiences an annual rainfall of less than 1 mm 0. Interestingly, this is not the hottest desert on the planet though. The hottest temperature ever recorded on Earth was These measurements were part of a global temperature survey conducted by scientists at NASA's Earth Observatory during the summers of to In short, deserts are not just sand dunes and places where you might come across Bedouins and Berbers, or a place you have to drive through to get to Napa Valley.
They are common to every continent of the world, and can take the form of sandy deserts or icy deserts. In the end, the defining characteristic is their pronounced lack of moisture. In that respect, the polar regions are the largest deserts in the world, with Antarctica narrowly beating out the Arctic for first place.
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