What kind of desert is the sahara

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.

Although many deserts are sand-covered, most are not. Many desert landscapes are rocky surfaces. They are rocky because any sand-size or smaller particles on the surface are quickly blown away. Rocky deserts are barren wind-swept landscapes. As the wind moves southwestward, the air warms, dissipating moisture that might otherwise be released as rainfall. Locally, hot winds often lift sand and dust particles from the desert floor, spinning them upward through cooler air as dust devils or propelling them southwestward as fierce and blinding dust storms.

In the summer, daytime air temperatures across the Sahara often soar to well over degrees Fahrenheit, with the hottest air temperature meteorologists have ever recorded -- degrees -- occurring at Azizia, Libya, on September 13, Under the clear skies, the temperature may fall 40 degrees or more during an evening.

In the winter, freezing temperatures may occur in the northern Sahara, and milder temperatures, across the southern Sahara. Snow may fall occasionally in some of the higher mountain ranges and rarely, on the desert floor.

One of the most storied and unforgiving lands in the world, the Sahara -- the Arabic word for "desert" -- evokes a poignant sense of time and nature's power, of antiquity and legend, of wonder and mystery.

It has been the setting for some of the most pivotal chapters in Western history. DesertUSA Newsletter -- We send articles on hiking, camping and places to explore, as well as animals, wildflower reports, plant information and much more. Sign up below or read more about the DesertUSA newsletter here. It's Free. Enter E-Mail address:.

Enter Email:. The large mammals are native to North America and eventually made their way across the Bering Isthmus between 3 and 5 million years ago, according to a study in the Research Journal of Agriculture and Environmental Management in Camels were domesticated about 3, years ago on the Southeast Arabian Peninsula, to be used for transportation in the desert, according to the University of Veterinary Medicine, Vienna. Camels, also known as the "ships of the desert," are well-adapted for the hot, arid environment, according to the San Diego Zoo.

The humps on a camel's back store fat, which can be used for energy and hydration in between meals. Camels store energy so efficiently that they can go more than a week without water and several months without food. Other residents of the Sahara include a variety of gazelles , addax a type of antelope , cheetahs , caracals, desert foxes and wild dogs, according to the Sahara Conservation Fund. Many reptile species also thrive in the desert environment, including several species of snakes , lizards , and even crocodiles in places where there is enough water.

Several species of arthropods also call the Sahara home, such as the dung beetle, scarab beetle, " deathstalker " scorpions and many types of ants. Plant species in the Sahara have adapted to the arid conditions, with roots that reach deep underground to find buried water sources and leaves that are shaped into spines that minimize moisture loss.

The most arid parts of the desert are completely void of plant life, but oasis areas, such as the Nile Valley, support a large variety of plants, including olive trees, date palms and various shrubs and grasses. The Sahara alternates from being a dry, inhospitable desert and a lush, green oasis about every 20, years, according to a study published in the journal Science Advances in The study's authors examined marine sediments containing dust deposits from the Sahara from the past , years.

The team found that the cycle between a dry and a green Sahara corresponded to the slight changes in the tilt of Earth's axis, which also drives monsoon activity. When the Earth's axis tilted the Northern Hemisphere just a single degree closer to the sun about Archaeologists have discovered prehistoric cave and rock paintings and other archeological remains that have shed light on what life was like in the once-green Sahara.