The Sahara

The Sahara could be the world's largest hot desert and among the harshest environments on the planet. It is third largest desert overall after Antarctica and the Arctic, which are cold deserts.

At 3.6 million square miles (9.4 million square kilometers), the Sahara, that is Arabic for "The Great Desert," engulfs nearly all of North Africa. The desert covers large parts of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Western Sahara, Sudan and Tunisia.

The Sahara is bordered by the Atlantic Ocean on the western edge, the Atlas Mountains and the Mediterranean Sea to the north, the Red Sea on the east, and the Sudan and the valley of the Niger River on the south. The Sahara is divided into western Sahara, the central Hoggar (Ahaggar) Mountains, the Tibesti Mountains, the Air Mountains, a location of desert mountains and high plateaus, Ténéré desert and the Libyan desert, that is probably the most arid region.

In the north, the Sahara reaches to the Mediterranean Sea in Egypt and portions of Libya. In Cyrenaica and the Maghreb, the Sahara experiences a more Mediterranean climate with a winter rainy season.

Major cities located in the Sahara include Cairo, Egypt; Tripoli, Libya; Nouakchott, the capital of Mauritania; Tamanrasset, Ouargla, Bechar, Hassi Messaoud, Ghardaia, and El Oued in Algeria; Timbuktu in Mali; Agadez in Niger; and Faya-Largeau in Chad.

Climate and geography of the Sahara

The Sahara's northeasterly winds can reach hurricane level and often give rise to sand storms and dust devils. 1 / 2 of the Sahara receives significantly less than an inch of rain each year, and the remainder receives around 4 inches (10 centimeters) per year. The infrequent rain is generally torrential.

The greatest peak in the Sahara could be the volcano Emi Koussi (11,204 feet or 3,415 meters) in the Tibesti Mountains in northern Chad. The desert's other mountains and mountain ranges are the Aïr Mountains, Hoggar (Ahaggar) Mountains, Saharan Atlas, Tibesti Mountains, Adrar des Iforas and the Red Sea hills.

Many individuals imagine the Sahara as dotted with sand dunes, and the desert comes with its share of ergs, which are large areas of shifting sand dunes, with a few of some of them reaching 590 feet (180 meters). However, most of the Sahara is characterized as rocky hamada, a type of desert landscape that has hardly any sand and is comprised of primarily barren, hard, rocky plateaus.

With the exception of the Nile River, the Sahara's rivers and streams are irregular or seasonal. The Nile crosses the desert from its origins in central Africa to empty into the Mediterranean.

The central part of the Sahara has extremely limited vegetation. The northern and southern reaches of the desert, combined with the highlands, have areas of sparse grassland and desert shrub, with trees and taller shrubs.

Animals of the Sahara

Tens of thousands of years ago, the Sahara had enough water so that folks and animals could survive on the edge of the desert. There is evidence that the region surely could sustain river animals such as crocodiles. Fossils of dinosaurs, including Afrovenator, Jobaria and Ouranosaurus, have also been discovered in the desert.

Prehistoric rock paintings also depict cattle, giraffes, elephants and lions that roamed a once-lush Sahara.

Today, there's little water or vegetation to sustain life in many part of the Sahara. Some exceptions are the Nile Valley, a few oases, and the northern highlands, where Mediterranean plants such as the olive tree are located to grow. The change occurred in about 1600 B.C., after shifts in the Earth's axis increased temperatures and decreased precipitation.

Camels, frequently connected with the Sahara, were introduced to the desert around 200 A.D. Their advantages within the horses they replaced include soft feet which are aligned so that they'll move quickly and easily through sand and their capability to go for approximately 17 days without food or water.

Rodents, snakes and scorpions thrive in the desert environment. The desert is home to the deathstalker scorpion, which may be nearly 4 inches (10 cm) in length. Its dangerous venom contains large levels of agitoxin and scyllatoxin.

On the list of 40-plus species of rodents in the Sahara could be the jerboa, related to the mouse, rat and squirrel. To keep cool, the jerboa burrows within the desert's sands to more humid soils.

The Addax nasomaculatus, also called the screwhorn antelope, could be the Sahara's largest indigenous mammal. It travels in small herds through the entire Western Sahara, Mauritania and Chad. In place of drinking tap water, it sucks moisture from the desert grasses and bushes. Its oversized hooves make the addax adept at moving through the Sahara's loose sand.

Jackals and several kinds of hyenas are among the carnivores that roam the Sahara. Weighing significantly less than 3 pounds (1.4 kg), the Mall Fennec Fox is another carnivore that makes its home in tunnels in the sand 

Thanks