The Sahara is the largest and best known hot desert on earth. Due to being considered cold deserts, only the Arctic and Antarctic measure larger in overall area.
In addition, the majority of the desert lies in the northern part of Africa. The total area of the Sahara also compares to the combined surface area of the United States and China combined.
This desert also draws its name from the ancient Arabic word for desert. The boundaries of the region remain roughly marked by the Atlas Mountains in the north, the Red Sea in the east, the Atlantic Ocean in the west, and the Niger River valley in the south.
Prior to roughly 3,600 years ago the region possessed a rather different climate and was actually quite lush with vegetation.
Sahara Geographical Variety
The geological marvel that we call the Sahara possesses an extensive variety of geographical features.
In a total area the desert measure roughly 3.5 million sq mi (9 million sq km). The majority of the features of the Sahara are shaped by wind movement and erosion.
The expansive sand dunes remain the most prominent and extensive of its features. Also, present within its boundaries are sand seas, dry valleys, dry lakes, stone plateaus, and salt flats.
With the exception of the Nile river, streams and waterways are scarce. Fed by underground water supplies, oases remain infrequent and typically small.
Some of the outlying portions of the region encompassed by the Sahara possess a more moderate climate, yet the majority of its area receives extremely little rainfall. Most of the desert receives less than 4 in (10 cm) of rain per year.
The region regularly suffers extremely high temperatures. The average temperature is approximately 104F (40C), yet on occasion, the temperature reaches a high as 122F (40C).
A slight wind almost constantly blows throughout the region. Occasionally, forces drive these winds to rather extreme velocities, forming powerful and dangerous sandstorms.
Sahara Flora and Fauna
The Sahara divides into three rather distinct biogeographical zones. The flora native to each zone varies dramatically, and the majority of the species concentrate in the outlying regions.
In total, about 2,800 species of plants also live within the boundaries of the Sahara. Examples of these include palms, acacia trees, grasses, and spiny shrubs.
Fauna endemic to the Sahara includes camels, gazelles, scorpions, various reptiles, and several species of foxes. Several species of small crocodiles also live in the Nile river and larger oases.