Download Global Atmospheric Circulation Air moves between the equator and

Global Atmospheric Circulation
Air moves between the equator and the poles – this is affects the Earth’s climate
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Winds are large scale movements of air caused by differences in air pressure.
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Differences in air pressure are caused by differences in temperature between the equator and the poles.
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Winds move from areas of high pressure to areas of low pressure.
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Winds are part of global atmospheric circulation loops or cells. These loops have warm rising air which creates a low pressure belt and cool falling air which creates a high pressure belt.
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There are three loops in each hemisphere – Hadley cells from the equator (0⁰) to 30⁰N and S, Ferrel cells, 30⁰N and S to 60⁰ N and S and Polar cells, 60⁰N and S to 90⁰N and S.
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Choose the correct title for the boxes below; Tropical Storm, Polar cell, Hadley cell, Ferrel cell
This is the largest of the 3 cells. Within this cell,
These cells lie between the others. In these latitudes
Cold, dense air descends at the higher latitudes and
surface winds blow towards the equator and then rise
the cooler air from the poles meets the warmer air
moves towards the lower latitudes. As it does so, the
as they are heated. At high altitudes this air then
from the tropics, causing the air to rise. This often
air warms and begins to rise, known as a polar front.
moves towards the poles, descending between 30 & 40⁰
occurs around the latitude of the UK and is one of the
N and S to form areas of high pressure. It is under
reasons why the UK often experiences unsettled
these conditions of high pressure that many of the
weather.
world’s deserts are formed, including the Sahara.
The rising air in the Hadley cell at the equator forms an
area of low pressure at the surface. The intensity of
the sun’s rays here means that air rises rapidly and
huge cumulonimbus rain clouds are formed, associated
with thundery downpours.