World's top 10 fascinating natural phenomena (7)

13:21, November 20, 2009      

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7. Fire Whirls



A fire whirl, also known as fire devil or fire tornado, is a rare phenomenon in which a fire, under certain conditions --depending on air temperature and currents--, acquires a vertical vorticity and forms a whirl, or a tornado-like effect of a vertically oriented rotating column of air. Fire whirls often occur during bush fires. Vertical rotating columns of fire form when the air currents and temperature are just right, creating a tornado-like effect. They can be as high as 30 to 200 ft tall and up to 10 ft wide but only last a few minutes, although some can last for longer if the winds are strong.
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