Low and high pressure circulations are reversed in opposite hemispheres
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Cyclones and Anti-cyclones

The Earth's spin causes the wind to curve. This is called the Coriolis Effect, named after Gaspard Coriolis who first worked out the mathematics involved. The wind in the northern hemisphere curves to the right and the wind in the southern hemisphere curves to the left.

When the wind swirls counter-clockwise in the northern hemisphere or clockwise in the southern hemisphere, it is called cyclonic flow. When the wind swirls clockwise in the norther hemisphere or counter-clockwise in the southern hemisphere, it is called anticyclonic flow. An example of cyclonic flow is the flow around a low pressure area while an example of anticyclonic flow is the flow arond a high pressure area. A hurricane is a cyclone.


Last modified January 8, 2010 by Randy Russell.

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