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?
|
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.
|
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!