Winds

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Winds

• Cornell Notes

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• Moving Air
• It is created by differences in air pressure. The
  greater the difference, the stronger the wind is.
• The difference in air pressure is usually caused
  by the unequal heating of the Earth.
• Ex Air at the Equator is warm and less dense so
  it rises. As it rises, it creates an area of low
  pressure. At the North Pole, air is cold and very
  dense. It is heavy and sinks. This creates an
  area of high pressure. Air usually moves from
  high pressure to low pressure.

• What is Wind and why does it move?

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• What are Pressure Belts?

• Because wind moves from a high pressure to a low
  pressure, it usually moves from the Poles to the
  Equator. As the warm air rises over the Equator,
  it begins to cool. Eventually, it stops rising
  and moves to the Poles. This happens about
  every30 of latitude.

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• Winds dont blow directly north or south because
  of the rotation of the Earth. The Earths
  rotation causes wind to travel in a curved path
  rather than in a straight line.
• Winds in the Northern Hemisphere curve to the
  right and winds in the Southern Hemisphere curve
  to the left.

• What is the Coriolis Effect?

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• What are the two main types of Winds?

• Both types are caused by uneven heating of the
  Earths surface and by pressure differences
• Local Winds
• Global Winds

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• Are part of a pattern of air circulation that
  moves across the Earth
• They travel longer distances than local winds
• They travel in a specific direction
• Trade Winds blow from 30 latitude to the
  equator The trade winds meet in an area called
  the Doldrums (Area of low pressure around the
  equator where there is very little wind due to
  air rising) and the Horse Latitudes (Area around
  30 N and 30S where sinking air causes an area
  of high pressure and winds are weak)

• What are the characteristics of Global Winds?

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• Westerlies wind belts found in both Northern and
  Southern Hemispheres between 30 and 60
  latitudes that flow toward the poles in the
  opposite direction of the trade winds
• Polar Easterlies wind belts that extend from the
  Poles to the 60 latitude in both Hemispheres
• Jet Streams narrow belts of high-speed wind that
  blow in the upper troposphere and lower
  stratosphere. They can reach speeds of 500 km/h.
  These are the only global winds that do not
  follow regular paths around the Earth. The Jet
  Stream controls the movement of storms so
  meteorologists can track storms by following it
  and airplane pilots can save time and fuel by
  flying in the direction of the Jet Stream.

• Global Winds continued.

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• Winds that are influenced by the geography of an
  area
• Ex an ocean shoreline will create different
  winds because during the day, the land heats up
  faster than water. The land heats the air above
  it and this wind is pushed out of the way when
  the cool air above the water moves in to take its
  place. At night, land cools faster than water,
  cooling the air above the land. This causes a
  wind to move from the land to the water.

• What are Local Winds?