2006 Philadelphia Annual Meeting (22–25 October 2006)

Paper No. 2
Presentation Time: 8:20 AM

THE UNIQUE DAMAGE POTENTIAL OF NORTHERN HURRICANES


COCH, Nicholas K., School of Earth & Environmental Science, Queens College - CUNY, 65-30 Kissena Blvd, Flushing, NY 11367-0904, nicholas.coch@qc.cuny.edu

Inhabitants of the Northeast U.S. believe that hurricanes happen only along palm-fringed coasts far to the south. They think that the cold waters north of the Gulf Stream prevent, or greatly weaken, any hurricane making a landfall in this region. My research on 370 years of historic hurricanes in this region has shown that the actual situation is quite different. There is a detailed record of major destruction by landfalling hurricanes in 1635, 1815, 1821, 1893, and 1938. The unique topographic, oceanographic, geographic, and demographic characters of this area amplify hurricane damage so that a hurricane hitting the North does the same damage as a hit by the next-higher Saffir-Simpson category hurricane in the South. The nature of northern hurricanes, and the changes they undergo as they move northward, also amplify damage. Their translational velocity increases as they leave the southern zone of weaker easterly flow and enter the temperate zones of stronger westerly flow, where upper level winds are faster. Their radius of maximum winds increase 2-3 times over southern hurricanes. This change increases storm surge damage along the coasts well as the areal extent of wind damage inland. Their almost universal coast-normal track at landfall carries the destructive right side hundreds of miles inland. In the north, there is also a greater chance of a weakening hurricane being revitalized by merging with an extratropical low pressure system. Northern hurricanes may be more infrequent, but the record shows that their potential damage could be catastrophic. The inevitable landfall of a northern hurricane along the most developed and populated hurricane-prone coastal segment in America has the potential to be a national disaster.