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Geography

The Spatial Dynamics of Desertification Fronts Along the Sahel Boundary

Quick fact

Despite popular images, the Sahara's southern edge does not advance as a solid wall of sand. Instead, desertification fronts are patchy, oscillating zones that can shift hundreds of kilometers between years, driven more by rainfall variability than by sand dunes encroaching.

Why this is interesting

You might picture desertification as a sand dune creeping southward, swallowing villages one by one. But satellite images tell a different story—the desert's edge is a patchwork that appears to breathe, not march.