- Hurricanes can trigger swarms of weak earthquakes and
even set the Earth vibrating, according to the first study of such effects.
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- When Hurricane Charley slammed into Florida in August
2004, physicist Randall Peters of Mercer University in Macon, Georgia,
had a seismometer ready to monitor any vibrations in the Earth's crust.
He did so for over 36 hours as Charley travelled briefly over Florida,
then slid back out into the Atlantic.
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- As the hurricane reached land, the seismometer recorded
a series of "micro-tremors" from the Earth's crust. This happened
again as the storm moved back out to sea. Then, as Charley grazed the continental
shelf on its way out, it caused a sharp seismic spike. "I suspect
the storm triggered a subterranean landslide," says Peters.
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- More surprisingly, the storm also caused the Earth to
vibrate. The planet's surface in the vicinity of the hurricane started
moving up and down at several frequencies ranging from 0.9 to 3 millihertz.
Such low-frequency vibrations have been detected following large earthquakes,
but this is the first time a storm has been found to be the cause
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- www.arxiv.org/physics/0506162
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- From issue 2506 of New Scientist magazine, 01 July 2005,
page 19
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- © Copyright Reed Business Information Ltd.
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- http://www.newscientist.com/article.ns?id=mg18625065.900
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