The Real Way We Should Classify Hurricanes: By Their Energy

I disagree! As a person who lived in Houston for twenty years classifying hurricanes by their energy is rather useless number. It is probably more useless than the current classification scheme. The problem with classifying hurricanes is relating their probable effects to the people in the area around the land fall. For the people in harms way, it is all about disaster preparations and they want to know about four things, wind, rain, storm surge, and location. The wind and rain components of Sandy were pretty mild compared to most hurricanes/tropical storms. Sandy made landfall as a tropical storm and fortunately kept moving. That’s the good news. The biggest problems with this storm was the storm surge and its location. In this case the residents of New Jersey and New York had a case of bad luck. As McNoldy wrote, “The storm surge, combined with a full moon and high tide, affected hundreds of miles of highly populated coastline.” From the news reports we can see that this area was dramatically unprepared for a storm surge of this size. Disaster preparations for this storm were an epic failure of poor planning. The obvious solution to the storm surge problem is to build a seawall. It blocks your view of the sea but some days the sea is not your friend.

As an example when I was living in Houston, I was amazed that people would build beach houses on west Galveston Island. Every ten years or so a hurricane would come along and clean off the west side of the island. In a couple of years the houses would be rebuilt. The east side of Galveston Island is protected by a seawall. The seawall was built as a response to the 1900 hurricane. For the most part it protected the city of Galveston well although the seawall was over-topped by the 1915 hurricane,  severely damaged by Hurricane Alicia in 1983, and over-topped again by Hurricane Ike in 2008. I remember Hurricane Alicia well. The eye of the hurricane passed over our house. Live and learn!

Hurricane Sandy

In sheer power, Hurricane Sandy ranks second among modern hurricanes, beating even Hurricane Katrina, according to Brian McNoldy, a hurricane researcher at the University of Miami.

Out in the Atlantic Ocean, Sandy was the most energetic tropical cyclone in history, thanks to its massive wind field.

Once Sandy ramped up to a Category 1 hurricane and slammed into New Jersey, the storm’s integrated kinetic energy was second only to Hurricane Isabel in 2003, McNoldy wrote in a blog post.

"It stood out to me that this was a pretty unique case of a rather weak storm as wind speeds go, but huge on the impact scale," McNoldy told OurAmazingPlanet.

Integrated kinetic energy (IKE) is a new scale designed to better convey the destructive power from both a hurricane’s wind and storm surge. It’s a measure of the wind speed integrated over how wide an area the winds are blowing. The U.S. government patented IKE in 2007. The Saffir-Simpson Scale, used by the National Weather Service, only reports top wind speeds.

The IKE scale helps explain why Hurricane Sandy, which quickly weakened after landfall, created such widespread flooding and damage, McNoldy wrote. The storm surge, combined with a full moon and high tide, affected hundreds of miles of highly populated coastline. The metric also incorporates the storm’s enormous size: The wind field was so large that tropical storm force winds (45 mph/ 72 kph) extended 485 miles (780 kilometers) out from the center at landfall. (Out at sea, the wind field reached a maximum extent of 520 miles, or 835 km.)

In modern records, Sandy’s IKE ranks second among all hurricanes at landfall, higher than devastating storms like Hurricane Katrina, Andrew and Hugo, and second only to Hurricane Isabel in 2003, McNoldy calculated.

Sandy’s IKE was more than 140 Terajoules, meaning it generated more than twice the energy of the Hiroshima atomic bomb, McNoldy wrote. At any given moment, many hurricanes contain more energy than an atomic bomb in their surface winds alone, he wrote.

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The Real Way We Should Classify Hurricanes: By Their Energy
Mon, 05 Nov 2012 22:22:00 GMT