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A Pulsing Desert

The Sahara Desert conjures up images of merciless heat and endless sands, scuttling scorpions, deadly vipers, gritty winds, elusive water—but it wasn’t always like that. The Sahara has a long history of changing climate, when the sands give way to water and humans brave the elements and survive. The Fezzan region in southwest Libya is the beating heart of the Sahara. Though this apparent inferno receives less than an inch of rain a year and holds the world heat record, it actually harbours tiny gem-coloured lakes: the dehydrated reminders of a time when groundwater was much closer to the surface. 200,000 years ago, a lake the size of England spread across the sands, and ancient channels testify the existence of rivers, making the land not only tolerable, but farmable—human communities rose and fell with the water like a pulse. The Sahara Desert might have even been one of the paths our ancestors took on their journey out of Africa. To locate and map these ancient waterways, researchers have used radar images to direct ground crews to study the sites, but the images of the Fezzan region above, however, were taken by photographer George Steinmetz using an ultra-light paraglider.

(via canthemannons)