Deserts are hyper-arid, arid and semi-arid regions, with very low rainfall: less than 100 mm of annual rain in the hyper-arid portions, less than 250 mm in the arid portions and oscillating between 250 mm and 500 mm in the regions semiarid. Due to these physical conditions, deserts are difficult places for human and other living beings to adapt.
Located on the African continent, the Sahara desert is the second largest and one of the most famous in the world, its territorial extension is approximately 9 million square kilometers, being larger than the area of the Brazil. It is present in more than ten countries: Algeria, Chad, Egypt, Libya, Mali, Morocco, Mauritania, Niger, Tunisia and Sudan. It also extends to Ethiopia, Djibouti and Somalia, where it receives local names. The Sahara desert is a natural divider of the African continent: to the north of the Sahara is Mediterranean Africa, to the south is Sub-Saharan Africa.
It features a high atmospheric pressure zone and low humidity levels. Its climate is one of the driest in the world (hyperarid). Temperatures are high, reaching over 50 °C during the day. However, it has a wide temperature range, and overnight temperatures drop dramatically, reaching the 0 °C mark. Rains are almost nil, they happen very rarely, usually torrential after long dry periods. The vegetal landscape is absent in most of this domain, present only in oasis areas.
Even with all these adverse survival characteristics, the Sahara is inhabited. The Tuareg (nomadic peoples) and the Bedouin (people who practice street commerce) stand out. In the Sahara desert, oases are the most sought after places for human settlement, as they present surface water tables outcropping, providing the appearance of vegetation.
The Sahara Desert gained great economic importance after the discovery of oil wells. However, for the oil to be extracted, high investments in infrastructure are necessary, making the activity not very profitable.
By Wagner de Cerqueira and Francisco
Graduated in Geography
Source: Brazil School - https://brasilescola.uol.com.br/geografia/deserto-saara.htm