Weather Lesson Three Wind Belts
CORIOLIS EFFECT Deflection of winds caused by Earth’s rotation. Winds are deflected to the right in the northern hemisphere, and to the left in the southern hemisphere.
WIND BELTS A series of parallel “belts” on Earth’s surface within which the winds generally move in a specific direction. Due to an unequal heating (insolation) of Earth’s surface, areas of different pressures are formed, which will result in the formation of convection currents.
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0° latitude – greatest insolation – air rises – low pressure. 90° latitude – least insolation – air sinks – high pressure. Due to Coriolis Effect, air bunches up and sinks at 30° latitude (creating high pressure) and rises at 60° latitude (creating low pressure). Therefore, 6 specific wind belts are set up on Earth’s surface.
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Global Wind Belts Equatorial Wind Belts
JET STREAMS Fast moving bands of air (up to 500 km/hr) between 6 to 12 kilometers high and 500 kilometers wide. Day to day (and seasonal) changes in weather patterns are affected by these jet streams.