Why do deserts exist near coasts?
Show answer & explanation
Answer: Cold currents prevent rain
Cold currents prevent rain ✓ — Correct! Cold ocean currents (like Humboldt off Chile, Benguela off Namibia) cool the air above them. Cold air sinks and holds less moisture, creating high-pressure zones with almost no rain. This creates coastal deserts like Atacama (driest place on Earth) despite being next to the ocean. Ironic desert beside water!
Mountains block all moisture — Wrong. Rain shadows do create deserts, but coastal deserts form from cold currents preventing rain, not mountains.
Sand from beaches spreads inland — Wrong. Beach sand doesn't create deserts. Coastal deserts form from lack of rainfall due to cold ocean currents cooling the air.
Go deeper: Atacama Desert
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