Where
are Deserts found?
Deserts
are mainly found around the Tropics of Cancer and Capricorn.orn.
What
are Deserts?
Deserts
are areas of the earth's surface which recieve less than 25cm or
10 inches of rainfall every year. They contain little or no vegetation.
The main characteristics of deserts are:
- rare
clouds
- little
rain
- very
hot days
- very
cold nights
How
did Desert get like this?
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You
may be wondering "If deserts are so hot......why are they
found along the tropics and not at the equator where the earth's
temperatures are the highest?". The diagram on the left should
explain this!
A. As you would expect, temperatures at the equator are
highest. Warm air rises containing evaporated moisture.
B. The air cools, condenses and forms clouds.
C. Heavy equatorial rainfall occurs (like in the rainforest!)
D. The cool, dry air then begins descending. The air warms
up. Any moisture in the air is held as water vapour (invisible).
E. Cloudless sky.
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Because
the tropics are largely cloudless they get very hot during the day.
There are few clouds to insulate these areas during the night. Therefore,
temperatures drop to very low levels overnight. It's just like going
to bed without any blankets!
What
is the impact of humans on the Desert?
Deserts
are increasing in size daily. This is partly due to human actions.
Poor farming techniques, such as overgrazing and overcultivation
in areas of savanna grassland, are causing soil erosion and desertification.
What
is the future for the Desert? - Sustainable Development
Coming
soon!
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