Dune in the Sahara desert

The Sahara desert

The Sahara has one of the harshest climates in the world. It stretches right across northern Africa, from the Atlantic Ocean to the Red Sea. It reaches to the Mediterranean in the north, and to the Niger River in the south. It dominates 11 African countries and covers between 9 and 10 million square kilometres. In other words, the Sahara is considerably bigger than Brazil, nearly three times the size of Japan, and roughly 20 times the size of Norway. Its awe-inspiring scale is well-expressed by the Arabic word erg, (irq) meaning ocean – and the Sahara contains not just one ‘ocean’ of sand, but several. The main ones are the Occidental (Western) Erg and the much bigger Eastern Erg. With shifting, windswept dunes stretching to the horizons, the ergs resemble many people’s picture of the desert.

But there is much more to the Sahara than sand; there are mountains (including the Hoggar range in southeastern Algeria) and huge swathes of scrub, jujuba, and other desert grasses. The Sahara is sparsely dotted with green oases. Less invitingly, there are also wastes covering thousands of square kilometres, where virtually nothing exists besides a thin scattering of pebbles on flat, bare ground. More hospitable parts of the Sahara are home to a great variety of wildlife. Day-time heat in the desert can reach a hard-to-imagine 55ºC, while at nightfall the temperature plunges to around 10ºC. Between December to February freezing temperatures are not uncommon at night.

The Algerian town of In Salah, in the middle of the desert, is slowly being cut in two by a huge, creeping sand dune. The leading part of the dune – it’s moved by desert winds – takes 10-20 years to bury a house completely. Meanwhile the back end follows, gradually uncovering houses that were swallowed up years before. When a buried house emerges after 50 years or so under the sand, the children and grandchildren of the original owners can repair it and move in.

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Photo: DigitalVision