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Extreme Winds - Tornadoes and Hurricanes

The spinning of the Earth causes winds to move in a circular motion. How does this motion sometimes speed up to produce the dramatic winds of a hurricane or tornado?

The key is what we call angular momentum. A large object, spinning slowly, will speed up dramatically when its diameter shrinks, just as a skater can spin faster by pulling her arms in.

This is precisely what causes the birth of extreme winds - when a spinning air mass gets pulled tighter, it spins faster, leading to the high wind speeds of tornadoes and hurricanes.

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Last modified March 26, 2010 by Randy Russell.

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