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Little known about tree-snapping wind

CHASE SQUIRES and DAVID KARP
Published August 19, 2004

PUNTA GORDA - The pine trees were not blown over. They were not ripped from the ground. They just snapped.

The towering trees that once provided cover in this coastal town are now just tall stumps.

What remains is a forest of wood poles.

The force inside Hurricane Charley that left this strange mark on the landscape is called a mesovortex. Scientists are still trying to understand this powerful force of nature, which only exists inside hurricanes.

"We really don't know that much about these things," said John Schroeder, an assistant professor of atmospheric science at Texas Tech University.

Mesovortices are born in the powerful winds that surround the eye of the storm. As the hurricane spins, tiny swirls of winds rip off from the center wall and act like small-scale tornadoes. Imagine a circle of leaves blowing in fall - then increase the speed a thousand times.

These swirls form their own center of destruction, moving like an out-of-control car that has run off the highway. They can rotate at hundreds of miles per hour, scientists say.

"They are very selective in what they destroy," said Dr. Jim Kossin, a researcher at the Cooperative Institute for Meteorological Satellite Studies at the University of Wisconsin in Madison.

Scientists agree that the phenomenon is found in many, if not all hurricanes, but the debate goes on over how the mesovortices operate - and what causes them to form.

Kossin, for example, recently published a paper on mesovortices found last year in Hurricane Isabel.

Before Hurricane Charley made landfall, Texas Tech sent a team to southwest Florida to study the storm. Members set up instruments in Sarasota to measure wind speed, Schroeder said.

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