Hurricanes occur during cool periods as well
Global warming may not worsen hurricanes
Hurricanes occur during cool periods as well
mongabay.com
May 28, 2007
A team of scientists have found evidence of intense hurricane activity during both cool and warm periods reports The New York Times. The findings suggest that factors other than sea temperature play a role in the formation and intensity of tropical storms.
Analyzing sediments of a lagoon on the Puerto Rican island of Vieques and in the New York, scientists from the Woods Hole Oceanographic Institution found a strong correlation between the intensity of storms along the Atlantic coast and the strength or weakness of the El Niño in the Pacific Ocean and the intensity of monsoons in West Africa.
“Comparison of the sediment record with palaeo-climate records indicates that this variability was probably modulated by atmospheric dynamics associated with variations in the El Niño/Southern Oscillation and the strength of the West African monsoon, and suggests that sea surface temperatures as high as at present are not necessary to support intervals of frequent intense hurricanes,” write Jeffrey P. Donnelly & Jonathan D. Woodruff of Woods Hole. “To accurately predict changes in intense hurricane activity, it is therefore important to understand how the El Niño/Southern Oscillation and the West African monsoon will respond to future climate change.”
Hurricane Katrina. Courtesy of NASA |
The findings add to the complexity of understanding hurricane activity. Some scientists have warned that climate change could increase the frequency and intensity of such storms, while others have said that hurricanes occur on a cyclical basis and that we are merely in the midst of a particularly active period.
The article is published in Nature.
CITATION: Jeffrey P. Donnelly and Jonathan D. Woodruff (2007). Intense hurricane activity over the past 5,000 years controlled by El Niño and the West African monsoon. Nature 447, 465-468 (24 May 2007) | doi:10.1038/nature05834
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