How Fast Is Sand Dune March?

Barchan sand dunes advance 10-30 metres per year — slow, but enough to swallow roads, buildings and ancient cities over time. The Sahara itself is currently expanding southward at roughly 48 km per year along its desertification front.

The southern edge of the Sahara is advancing at roughly 48 km per year, swallowing villages in real time.

• 15× faster than grass grows
• About 5× slower than wound healing