Although the memory of Hurricane Katrina is still fresh (even more so for fans of Treme), New York City on Monday morning will still resemble New York City, not a post-Katrina New Orleans. Let’s get some perspective. Hurricanes, or tropical cyclones as they are known worldwide, are characterized by a region of extreme low pressure at the center that is surrounded by thunderstorms, causing powerful winds and heavy rain. The lower the pressure and the stronger the winds, the more intense the storm. The Saffir-Simpson Hurricane Scale only categorizes storms by wind speed, although central pressure is also a good indicator of hurricane strength.
Right now, Irene is hanging out about 100 miles south of Ocean City, Maryland. The average sustained wind speed is 80 mph, which makes it a Category 1 storm, and the pressure at the eye of the storm is 951 millibar. When the winds slow to 73 mph, it will become a tropical storm. When Hurricane Katrina hit New Orleans on August 29, 2005, it was a Category 3 storm with sustained winds of 125 mph and pressure of 920 millibar.
Katrina was the costliest tropical cyclone ever, with damage exceeding $100 billion. It also was one of the deadliest, claiming 1836 lives. But let’s talk about another storm. The most intense tropical cyclone ever was Typhoon Tip in 1979. Tip was positioned in the north western Pacific Ocean, and it made landfall on Guam and southern Japan. Although it didn’t claim as many lives as Katrina, the statistics are staggering. The highest sustained winds were 190 mph for one minute and 160 mph for ten minutes. The pressure at the eye of the storm reached an unheard of 870 millibar. It was also the largest storm ever, extending 1380 miles across, which is half the area of the continental United States. Typhoon Tip had such extreme winds, that it ranks as a hypothetical Category 6 on the Saffir-Simpson Scale. This means that the storm’s potential damage is beyond catastrophic.
Hurricane Irene may damage some roofs and fell trees, but we will emerge relatively unscathed. In comparison, read the description of a Category 5 hurricane below:
"People, livestock, and pets are at very high risk of injury or death from flying or falling debris, even if indoors in mobile homes or framed homes. Almost complete destruction of all mobile homes will occur, regardless of age or construction. A high percentage of frame homes will be destroyed, with total roof failure and wall collapse. Extensive damage to roof covers, windows, and doors will occur. Large amounts of windborne debris will be lofted into the air. Windborne debris damage will occur to nearly all unprotected windows and many protected windows. Significant damage to wood roof commercial buildings will occur due to loss of roof sheathing. Complete collapse of many older metal buildings can occur. Most unreinforced masonry walls will fail which can lead to the collapse of the buildings. A high percentage of industrial buildings and low-rise apartment buildings will be destroyed. Nearly all windows will be blown out of high-rise buildings resulting in falling glass, which will pose a threat for days to weeks after the storm. Nearly all commercial signage, fences, and canopies will be destroyed. Nearly all trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Long-term water shortages will increase human suffering. Most of the area will be uninhabitable for weeks or months." From the National Weather Service.
The above photograph is pretty much the reason for this whole post. Courtesy of KeystoneUSA-Zuma/Rex Features.
Of course I didn't mean to sound flippant. She's rolling in now, and it is pretty exciting...
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