Hurricane seasons are more active

This is a sediment core sample collected in a laguna along the Florida Panhandle. Photo: Jon WoodruffStudy examined evidence of hurricanes going back 1,500 years, identified factors that contribute to more active hurricane seasons.

For many Americans who live on the Atlantic coast, Andrew, Ivan and Katrina are more than just names – they are reminders of the devastating impact of cyclonic activity in the region during hurricane season. If it seems like hurricane seasons have been more active in recent years, you're on to something. According to a paper published in the August 13 issue of Nature, the frequency and strength of these powerful storms has grown in recent decades.
"We
are at levels now that are about as high as anything we have seen in the past 1,000 years," said Michael Mann, director of the Earth System Science Center at Pennsylvania State University and the lead author of the paper. Mann and his collaborators, Jeffrey P. Donnelly of the Woods Hole Oceanographic Institution, Jonathan D. Woodruff of the University of Massachusetts and Zhihua Zhang of Pennsylvania State University examined sediment samples from across the North Atlantic coast and statistical models of historic hurricane activities.