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Hurricane Ike Suggests Need to Modify Saffir-Simpson Scale Hurricane Measurement Metrics

Estimates of damage from Hurricane Ike and the reported death toll continue to rise far beyond what would be expected from the last Saffir-Simpson Scale reading of “a category 2 hurricane.”

Hurricane Ike’s larger than category 2 impact suggests need to modify Saffir-Simpson Scale hurricane measurement and communication metrics. It is heartbreaking to see and hear the stories of people who wouldn’t evacuate before the areas on the Texas coast because Hurricane Ike was “only a category 2 hurricane”. The reports and pictures from airborne helicopters indicate massive hurricane property damage and, unfortunately, loss of life from Hurricane Ike. I dedicate this post to these victims.

This begs the question, could this loss of life been reduced with better communication of risk to the people in the areas of projected impact, causing them to evacuate?

Places like Galveston, Bolivar, Crystal Beach, Gilchrest, High Island, etc. had lower evacuation rates than during Hurricane Rita. This could have been much, much worse if it hit a more densely populated area. But the loss of any life is undesirable (and potentially is preventable).

A friend of mine who lives on the Gulf Coast has repeatedly suggested to me that there is a need to have “less media hype” and “more factual metrics” when hurricanes approach. As you know I think about metrics a lot in terms of the Internet and business processes and I started thinking about this issue and the implications of it.

The last National Hurricane Center report before Hurricane Ike made landfall in Texas contains the following two paragraphs:

DATA FROM NOAA DOPPLER WEATHER RADARS AND RECONNAISSANCE AIRCRAFT
INDICATE MAXIMUM SUSTAINED WINDS ARE NEAR 110 MPH…175 KM/HR…
WITH HIGHER GUSTS. IKE IS A STRONG CATEGORY TWO HURRICANE ON THE
SAFFIR-SIMPSON SCALE AND COULD REACH THE TEXAS COAST AS A CATEGORY
THREE…MAJOR HURRICANE…JUST BEFORE LANDFALL. STRONGER WINDS…
AS MUCH AS 30 MPH HIGHER THAN AT THE SURFACE…COULD OCCUR ON HIGH
RISE BUILDINGS.

IKE REMAINS A VERY LARGE HURRICANE AND HURRICANE FORCE WINDS EXTEND
OUTWARD UP TO 120 MILES…195 KM…FROM THE CENTER…AND TROPICAL
STORM FORCE WINDS EXTEND OUTWARD UP TO 275 MILES…445 KM. DURING
THE PAST HOUR…HURRICANE FORCE WIND GUSTS HAVE BEEN REPORTED ON
GALVESTON ISLAND AND REPORTS FROM NOAA AND AIR FORCE RECONNAISSANCE
AIRCRAFT INDICATE SUSTAINED HURRICANE FORCE WINDS ARE JUST OFFSHORE
GALVESTON ISLAND.

I’m not certain how many years ago the National Hurricane Center started reporting Hurricanes in this format with the “hurricane force winds extend outward from the center ### miles” and “tropical force winds extend outward ### miles”, but I find that information useful as there is a significant correlation to size of the hurricane and the impact of the storm surge and geographic area that are affected. This is therefore extremely useful data, but it’s locked up in giant blobs of text that don’t allow it to be communicated effectively.

I’d like to therefore propose and suggest that the National Hurricane Center make the following modification the to Saffir-Simpson scale to the following new format:

Saffir-Simpson Scale number – hurricane force wind miles from center number – tropical storm force wind miles from center number

Hurricane Ike would have therefore been the following at landfall:
2-120-275

It is my opinion that this would be a much more useful as the overall radius of the hurricane force and tropical force wind fields would be communicated effectively and consistently instead of in inconsistent references. One could argue that you should use the circumference to make it more dramatic, but not all tropical cyclones are perfectly symmetric so I prefer usage of the existing communicated metric radius.

This humble blog post is clearly just the first of many conversations to openly discuss hurricane scale and metrics and creating this needed reform. The reform itself is more important than the exact final form of this reform prior to the start of the 2009 hurricane scale and metrics season. I look forward to seeing comments and other blog posts.

I look forward to someday having a clearer metric that can save more lives. Thank you for your participation in making this a reality!