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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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA