Study Finds Hurricanes Frequent in Some Cooler Periods

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Study Finds Hurricanes Frequent in Some Cooler Periods


J. Donnelly
On the Puerto Rican island of Vieques, members of the Woods Hole research team collected sediments left by hurricanes of earlier times.

By ANDREW C. REVKIN
Published: May 24, 2007
Over the last 5,000 years, the eastern Caribbean has experienced several periods, lasting centuries, in which strong hurricanes occurred frequently even though ocean temperatures were cooler than those measured today, according to a new study.


Intense hurricane activity over the past 5,000 years controlled by El Niño and the West African monsoon (Nature)
The authors, from the Woods Hole Oceanographic Institution, say their findings do not necessarily conflict with recent papers asserting a link between the region’s hurricane activity and human-caused warming of the climate and seas.

But, they say, their work does imply that factors other than ocean temperature, at least for thousands of years, appear to have played a pivotal role in shaping storminess in the region.

The study compared a 5,000-year record of strong storms etched in lagoon mud on the Puerto Rican island of Vieques with data on ocean temperatures and climate and storm patterns. The analysis is being published today in the journal Nature.

The Woods Hole team found that stormier spans, including one from 1700 until now, were associated with a relative paucity of El Niño warm-ups of the tropical Pacific Ocean and also with periods of heightened monsoon intensity in West Africa.

more:
http://www.nytimes.com/2007/05/24/science/earth/24storm.html