The nile river sahara desert and
This oasis is along one of the ancient watercourses discovered by geologists using Space Shuttle Topographic data.
Sahara desert facts
Goods such as gold, salt, slaves, cloth, and ivory were transported across the desert using long trains of camels called caravans. In the southern Sahara, the drying trend was initially counteracted by the monsoon , which brought rain further north than it does today. A geographical map of Africa, showing the ecological break that defines the Saharan area An oasis in the Ahaggar Mountains. The Nile, however, was impassable at several cataracts , making trade and contact by boat difficult. The wind may leave rippled surfaces in its wake. Hot, dry air masses primarily form over the North-African desert from the heating of the vast continental land area, and it affects the whole desert during most of the year. However, it is a myth that the nights are cold after extremely hot days in the Sahara. But around 10, years ago, a sudden burst of monsoon rains over the vast desert transformed the region into habitable land. The cheetah avoids the sun from April to October, seeking the shelter of shrubs such as balanites and acacias.
During these few thousand years, prehistoric humans left the congested Nile Valley and established settlements around rain pools, green valleys, and rivers.
Here, the local pressure on natural resources can be intense. If the weather is not suitable for camping, then you will spend this night of your tour at the Badawiya Hotel, Farafra.
Comparatively rare, they tend to form at the upwind edges of dune fields.
The Kiffian skulls are akin to those of the Late Pleistocene Iberomaurusiansearly Holocene Capsiansand mid-Holocene Mechta groups, whereas the Tenerian crania are more like those of Mediterranean groups. Activities Take a ten question quiz about this page.
But sandwiched between two periods of extreme dryness were a few millennia of plentiful rainfall and lush vegetation.
How big is the sahara desert
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. Here, the local pressure on natural resources can be intense. The dunes, with their various forms, raise many questions about the dynamics of their formation. The harsh climate of the Sahara is characterized by: extremely low, unreliable, highly erratic rainfall; extremely high sunshine duration values; high temperatures year-round; negligible rates of relative humidity ; a significant diurnal temperature variation ; and extremely high levels of potential evaporation which are the highest recorded worldwide. The prevailing air mass lying above the Sahara is the continental tropical cT air mass, which is hot and dry. Also, to be protected against rain-bearing weather systems by the atmospheric circulation itself, the desert is made even drier by its geographical configuration and location. Water The Sahara has only two permanent rivers and a handful of lakes, but it has substantial underground reservoirs, or aquifers. They constantly move around to find new areas to graze their livestock and hunt for food. Higher and more regular rainfall and cooler temperatures support woodlands and shrublands of date palm, acacias , myrtle , oleander , tamarix , and several rare and endemic plants. During periods of a wet or " Green Sahara ", the Sahara becomes a savanna grassland and various flora and fauna become more common. South is the Sahel region that sits between the desert and the African Savanna. The prevailing wind, which blows from the northeast toward the equator throughout the year, accounts for the desert's aridness. It began to dry up around years ago due to a gradual change in the tilt of the Earth's orbit. Flora and fauna The flora of the Sahara is highly diversified based on the bio-geographical characteristics of this vast desert.
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