What is a desert?
Where are deserts found?
How are deserts made?
Water action in deserts
Wind action in deserts
There are three main causes of deserts.
Most of the world deserts are made by the equatorial wind belts.
At the equator warm air is always rising. This created wind belts that blow north and south away from the equator.
When air descends at the tropics of cancer and capricorn it is too dry for clouds to form. No clouds means no rain producing Deserts. E.g. the Sahara desert
Rainshadow also produce Deserts. Any moisture in the air will fall as air passes high mountain ranges, so land beyond the mountains receives little or no rain. The Gobi desert is produced by Rainshadow.
Cold Currents also produce deserts.
The southwestern coasts of Africa and South America are swept by cold currents upwelling from the ocean floor. These currents cool the air that passes over them, causing the water in the air to fall as rain before it reaches the land. The Namib and Atacama desert have formed because of these cold currents.
The Rainshadow effect
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The Upwelling Effect