The place

The Sahara covers roughly the area of the United States, and most of it is not sand. Stony plains (reg), bare rock plateaus (hamada), dry valleys and volcanic mountains such as the Ahaggar and Tibesti make up the greater part. The great sand seas, or ergs, hold dunes that can rise more than 100 metres and move slowly with the wind. Days are hot and nights can be cold; in winter frost forms in the mountains. Rain is rare and can fail for years. Oases form where groundwater reaches the surface. The loudest sounds are wind and the hiss of blown sand, and on some dunes the sand itself booms as it slides.

History

The Sahara has not always been a desert. Shifts in the Earth's orbit have repeatedly brought monsoon rains north, and during the last such humid period, which ended around 5,000 years ago, it held lakes, grassland, hippos and crocodiles. People living then left rock paintings and engravings of giraffes, cattle, swimmers and dancers, notably at Tassili n'Ajjer in Algeria and Tadrart Acacus in Libya. As the land dried, many moved to the Nile and the Sahel. Later the camel made trans-Saharan trade in gold, salt, books and enslaved people possible. In the colonial era France, Britain, Italy and Spain drew most of the borders that cut across the desert today.

Why it matters for the living world

Despite its harshness, the Sahara has its own specialists: addax, dama gazelle, Barbary sheep, fennec fox, Saharan cheetah and desert-adapted plants that wait years for rain. Many of the large mammals are now very rare. The scimitar-horned oryx became extinct in the wild around 2000 and has been reintroduced in Chad since 2016. Oases and mountain refuges hold relict fish, crocodiles and trees from wetter times. The desert matters far beyond its edges too: dust lifted from the Sahara crosses the Atlantic and adds nutrients to the ocean and to the soils of the Amazon, and its heat drives weather patterns across Africa and Europe.

People of the place

Many peoples live in and around the Sahara. The Tuareg, who call themselves Kel Tamasheq or Imuhagh, are traditionally camel herders and traders in the central Sahara. The Tubu (Teda and Daza) live around the Tibesti, the Sahrawi in the west, and Arab and Amazigh communities across the north. Oasis farmers grow dates and vegetables with old systems of underground channels, called foggara in Algeria, that tap groundwater. Caravans still carry salt in parts of Niger and Mali. Today many Saharan people live in towns, work in mining, trade or tourism, or migrate, and many have lost grazing land to borders, conflict and drought.

What it faces

Climate change is expected to make the desert hotter and its margins less predictable. Hunting, often from vehicles, has wiped out most large antelope. Oil, gas, uranium and gold mining open roads and pollute water. Fossil groundwater, such as the Nubian Sandstone Aquifer, is being pumped faster than it is replaced. Armed conflict in the Sahel and Libya makes conservation and normal life difficult. On the southern edge, overgrazing and drought degrade land. Responses include reintroduction of oryx and addax in Chad and Niger, protected areas such as Termit and Tin Toumma in Niger, and regional efforts such as the Great Green Wall to restore land along the Sahel.

Sources

Written for Regenerative Voices from the sources above. Spotted something wrong? Tell us.