Some of the world's largest supplies of underground water exist beneath the Sahara Desert, supporting about 90 major oases there.
The Sahara is the world's hottest desert.
The Sahara covers large parts of Algeria, Chad, Egypt, Libya, Mauritania, Mali, Morocco, Niger, Western sahara, sudan and Tunisia.
Its surface area of 9,400,000 square kilometers (3,630,000 square miles) including the Libyan Desert and covers about 1/4 of the African continent.
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 Nigar River on the south.
The Sahara has one of the harshet climate in the world.
The Sahara Desert is the world’s largest hot desert, located in North Africa.
The Sahara used to be a lush region with many plants and animals. It began to dry up around 4000 years ago due to a gradual change in the tilt of the Earth's orbit.
The Sahara Desert is made up of sand dunes, sand seas, gravel plains, stone plateaus, salt flats, dry valleys, mountains, rivers, streams, and oases.
There is sparse grassland in some parts of the desert including the highlands and northern and southern parts of the desert.
The desert landforms of the Sahara are shaped by wind or by extremely rare rainfall and include sand sune field or sand seas, stone plateaus, gravel plains, dery valleys.
Many of its sand dunes reach over 180 meters (590 feet) in height.
Several deeply dissected mountains and mountain ranges, many volcanic, rise the desert.
Emi Koussi (huge extinct volcano), a peak in the Tibesti Mountains is 3,415 meters (11,204 feet) high and the highest point in the desert.
Snow may fall occasionally in some of the higher mountain ranges. On Feb. 18, 1979, low altitude areas of the Sahara desert recorded their first snowfall in living memory.
Most of the rivers and streams in the Sahara desert are seasonal or intermitted, the main exception being the Nile River, which crosses the desert from its origins in central Africa to empty into the Mediterranean.
There are some 20 or more lakes in the Sahara. Most of these are saltwater lakes. Lake Chad is the only freshwater lake in the desert.
Around two million people live in the Sahara Desert.
The people who live in the Sahara are mostly nomads. Nomads move from place to place.
Like all deserts, the Sahara harbors a relatively sparse community of wild plants, with the highest concentration occuring along the northern and southern margins and near the oases and drainages.
It is imposed adaptation on the plants.
For instance, near wadis and oases, plants such as date palms, tamarisks and acacia put down long roots to reach life-sustaining water.
From the Mediterranean vegetation which covered the Sahara mountains before they became a desert, only laurel and cypress trees remain in the region near gueltas.
Across the central, most arid part of the Sahara, the plant community comprises perhaps 500 species, which is extremely low considering the huge extent of the area.
Date palm trees, introduced by Arabs, is requisite for the existence of humans in the oasis; dates are very energetic food, trunks are used to make beams, leaves are used to make baskets, ropes, mats and covers for huts.
Camels are the main animal of the desert. They have a great capacity to resist heat and thirst. Even above 50°, they can stay without drinking water for many days.
Several species of fox live in the Sahara, including the fennec fox, pale fox and Ruppell's fox.
The addax a large white antelope, can go nearly a year in the desert without drinking. Other notable gazelles include the rhim gazelle and dama gazelle.
The northwest Africa cheetah, also known as the Sahara cheetah, is a subspecies of cheetah found in the northwestern part of Africa (particularly the central western Sahara desert and the Sahel).
Other animals include the monitor lizards, deathstalker scorpions, sand vipers, hyrax and small populations of African wild dog, red-necked ostrich, secretary birds...
There is also dung beetle which was a holy symbol to the ancient Egyptians and has some impressive adaptability.
Saharan rock art is a significant area of archaeological study focusing on the precious treasure carved or painted in the natural rocks found in the central Sahara desert.
There have been dinosaur fossils found in the Sahara Desert.
Daytime temperature can reach 58°C (136°F), but freexing temperatures are not uncommon at night. Its temperature can become as low as -6°C (22°F).
Sandstorms are very common in the desert. Brown clouds of sand cover the sky as wind blows and everywhere.
The word "Sahara" means "desert" in the Arabic language.
सहारा मरुस्थल के पश्चिम में स्थित, मरिसिनिया क्षेत्र में रेत के बड़े-बड़े टीले पाये जाते हैं. कुछ रेत के टिब्बों की ऊंचाई 180 मीटर तक पहुँच जाती है.
सहारा मरुस्थल, लगभग 92 लाख वर्ग किलोमीटर के क्षेत्रफल में फैला हुआ है. पश्चिम से पूर्व तक इसकी लम्बाई लगभग 4800 किलोमीटर तथा उत्तर से दक्षिण तक इसकी चौड़ाई 1800 किलोमीटर है.
सहारा मरुस्थल में दिन और रात के तापमान में काफी अंतर होता है.कभी कभी तो दिन का तापमान 56 डिग्री सेल्सियस तक पहुँच जाता है वहीं रात में यह 0 डिग्री सेल्सियस से भी नीचे चला जाता है.
सहारा मरुस्थल, संसार के लगभग 8 प्रतीशत थल भाग में फैला हुआ है. यह मरुस्थल 11 देशों में फैला हुआ है.
मरुस्थल में आपको कहीं-कहीं कुएं, नदियाँ और झरने दिखाई देंगे, इसी कारण यहाँ हरे-भरे मरुद्यान पाए जाते हैं. सहारा में खारे पानी की झीलें भी पाई जाती हैं.
सहारा में जीवन व्यतीत करना बेहद कठिन है फिर भी यहां 500 के अधिक जीव यहां पाए जाते है और लगभग 1000 के करीब पेड़ों की प्रजातियां भी यहां मिलती है.
ऐसा माना जाता है कि लगभग 6000 साल पहले सहारा में हरियाली हुआ करती थी लेकिन धीरे धीरे हरियाली से यह एक सबसे बड़े गर्म मरुस्थल में बदल गया.