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Time to rethink how hurricane strength is calculated?

Proposal improves Saffir-Simpson Hurricane Scale by swapping wind for pressure to better gauge damage

Hurricane Katrina from 2005 a massive storm with hidden dangers not reflected in the current hurricane Saffir-Simpson Scale.
Hurricane Katrina from 2005 a massive storm with hidden dangers not reflected in the current hurricane Saffir-Simpson Scale.

It may be time to change the hurricane scale to better represent the overall hurricane dangers.

Hurricane expert and seasonal tropical cyclone expert Dr. Philip Klotzbach at Colorado State University said using hurricane pressure is a better way to convey the potential damage from hurricanes compared to using conventional wind measurements.

Most who live in the hurricane belt know the Saffir-Simpson Hurricane Scale well. It is the current 1 to 5 rating system based on a hurricane’s sustained wind speed.

The scale’s utility as a single number simplifies messaging but has some pitfalls in that it fails to include all threats completely.

Much is missing from the formula, including winds surge, rain, and size, all of which can make a weaker storm much more dangerous.

Hurricanes are complex and not all storms are the same, which is why Klotzbach proposes using minimum sea level pressure as a better predictor for hurricane damage.

Take Hurricane Katrina in 2005. It hit as a Category 3, far weaker than Hurricane Charley’s Category 4 classification. But Katrina’s 125 mph winds caused Category 5 damage because it was much larger in relation, sending a massive 28-foot storm surge into a stretch of Mississippi. In contrast, Charley had higher pressure and higher winds but was much smaller than Katrina, resulting in less destruction focused around Port Charlotte and less rain.

Smaller storms and higher winds don't always equate to more damaging hurricanes.
Smaller storms and higher winds don't always equate to more damaging hurricanes. (.)

More accurate representation in higher latitudes

Pressure represents a better picture of strength as storms move into higher latitudes. When pressure drops, winds go up. But winds often come down while pressure stays low when storms travel northward into cooler water.

Hurricane Sandy was a classic example, packing a very low Category 3-4 pressure of 942 mb even though it came ashore as a Category 1 on the Saffir-Simpson rating.

More than half of all hurricanes are Categories 1 and 2, but those reaching Category 3 and higher are considered major hurricanes because of their potential for significant loss of life and damage.

While a published paper will soon be released by Klotzbach on this topic, it may take several years, if any changes are made.


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