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Geography

How Mountains Create Rain Shadows on Leeward Slopes

Quick fact

The leeward side of a mountain can receive less than 20% of the precipitation falling on the windward side, creating rain-shadow deserts like the Mojave in California.

Why this is interesting

Why is one side of a mountain lush and green while the other only a few kilometers away is a dry desert? The mountain itself is the answer—and it's not the rock that blocks rain, but the air.