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Wind: air in motion
On a windy day, have you noticed clothes flapping in the air, trees swaying
and bending, and your hair whipping around your face? There is so much
movement caused by a strong wind.
What causes wind?
Wind is air in motion. It is caused due to the
heating of air by the sun. The earth’s surface
consists of land and water. The two absorb heat at
different rates. The land heats up faster than water.
Also, some areas of the earth get direct sunlight
throughout the year. These areas are warm. Other
areas do not get direct sunlight, and so are colder.
The air in the hotter regions warms up and rises,
and cold air rushes in to take its place. This
movement of air is wind.
Types of winds A high pressure is
created over water.
There are two types of winds: upper winds and Air moves from the
surface winds. Upper winds blow ten kilometres high-pressure to the
above the earth’s surface. They are very strong and low-pressure area,
are spread over a vast area. These winds are also creating wind.
known as jet streams. On the other hand, surface
winds blow near the surface of the earth.
Am I dreaming or are
the birds flying faster?
Did you know?
Jet streams were
discovered by pilots
flying fighter planes
during the Second
World War.
They found their
planes flying slower
when moving against
the jet stream.
TICKER French scientist Gustave-Gaspard Coriolis first described the Coriolis effect in 1835.
On a windy day, have you noticed clothes flapping in the air, trees swaying
and bending, and your hair whipping around your face? There is so much
movement caused by a strong wind.
What causes wind?
Wind is air in motion. It is caused due to the
heating of air by the sun. The earth’s surface
consists of land and water. The two absorb heat at
different rates. The land heats up faster than water.
Also, some areas of the earth get direct sunlight
throughout the year. These areas are warm. Other
areas do not get direct sunlight, and so are colder.
The air in the hotter regions warms up and rises,
and cold air rushes in to take its place. This
movement of air is wind.
Types of winds A high pressure is
created over water.
There are two types of winds: upper winds and Air moves from the
surface winds. Upper winds blow ten kilometres high-pressure to the
above the earth’s surface. They are very strong and low-pressure area,
are spread over a vast area. These winds are also creating wind.
known as jet streams. On the other hand, surface
winds blow near the surface of the earth.
Am I dreaming or are
the birds flying faster?
Did you know?
Jet streams were
discovered by pilots
flying fighter planes
during the Second
World War.
They found their
planes flying slower
when moving against
the jet stream.
TICKER French scientist Gustave-Gaspard Coriolis first described the Coriolis effect in 1835.
