Air rises at the equator and sinks at the poles

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Transcript Air rises at the equator and sinks at the poles

Air rises at the equator and sinks at the
poles
• The equator receives more direct sun than other areas so the air is
less dense and rises to create low pressure.
• This warm air flows to the poles then cools and sinks creating high
pressure.
• The air is constantly in motion with this pattern called convection.
Pressure Belts
• Pressure Belts are found at every 30degrees on the globe.
• Air travels in the large circular patterns called convection cells.
• These cells are separated by areas of high and low pressure called
pressure belts.
Coriolis Effect
• Because the earth is rotating and curves, winds do not travel in
straight lines.
• The curving of the wind due to the Earth’s rotation and curve is
called the Coriolis effect
• The Coriolis effect causes winds to curve instead of flowing in
straight lines.
Polar Easterlies
• Wind belts that extend from the poles to about 60degrees North
and South
• In the northern Hemisphere the polar easterlies carry cold artic air
over the united states producing snow and freezing weather.
Westerlies
• The wind belts found between 30 and 60 degrees latitude in both
hemispheres are called Westerlies
• These flow TO the poles from west to east.
• These bring moist air to the United States and create rain and
snow.
Trade Winds
• Winds that blow from 30 degrees latitude to the equator are called
trade winds.
• The Coriolis effect causes trade winds to curve to the west in both
hemispheres.
• These winds used to help carry ships from Europe to the America’s
to help with trading goods, that’s why they are called trade winds.
Doldrums
• The area where the trade winds meet are called the doldrums.
• This area has very little wind because the warm rising air creates a
large area of low pressure.
Horse Latitudes
• These are at 30 degrees North and South
• The warm air that rose from the equator is now sinking in this area
and creating an area of high pressure.
• Winds in this area are very weak.
• Most of the worlds deserts are located in this area because the
sinking air is very dry.