USF professor proposes new hurricane rating system

A University of South Florida geoscience professor believes that a new hurricane scale can help individuals better prepare for storms. Recent research has backed her claims. 

Jennifer Collins, alongside co-authors Nadia Bloemendaal, Hans de Moel, Jantsje Mol, Priscilla Bosma and Amy Polen, first introduced the Tropical Cyclone Severity Scale in the scientific journal Environmental Research Letters, in 2021. 

The current rating system that the National Hurricane Center uses is the Saffir-Simpson Hurricane Wind Scale, which only takes into account wind severity – as its name implies. 

However, the new rating system was designed to consider storm surge and rainfall as well. 

Collins and some of her same co-authors wrote a secondary paper, published in the Scientific Reports journal last month. It included research about risk perceptions and how the scale could better encourage people to take precautionary measures for hurricanes (evacuations, et cetera). 

They oversaw an online experiment with 4,000 individuals who live in areas that are often impacted by hurricanes..

Collins and her colleagues created fictitious scenarios and asked participants if they understood the wind, storm surge and rainfall risks. Furthermore, based on these risks, would they evacuate or not. Half of the sample was given the Tropical Cyclone Severity Scale. 

Participants were more likely to evacuate for non-wind related factors based on the new rating system. 

Jennifer Collins speaking at the Symposium on Hurricane Risk in a Changing Climate event in Honolulu, Hawaii. Photo provided.

Collins, who has conducted evacuation research since Hurricane Matthew in 2016, has seen the impacts of hurricanes firsthand. Creating the scale was inspired by these past storms, she said. 

“I think the problem is that my research is showing that people are using the category of hurricane based on the Saffir-Simpson Hurricane Wind Scale to make their evacuation decisions,” Collins explained. 

“I also think that some of them probably don’t actually understand that the scale is simply measuring wind.” 

For example, Hurricane Florence, which was ranked as a Category 1 when it made landfall in the Carolinas in 2018, caused massive flooding and resulted in the deaths of more than 50 people. 

A 2014 study conducted by Edward Rappaport, who was the deputy director of the National Hurricane Center at the time, also played a role in developing the rating system. 

 “This study reported that when we consider fatalities, only 8% of fatalities are from wind,” Collins said. “Forty-nine percent are from storm surge and 27% are from rainfall.” 

These factors are described as hazards in the Tropical Cyclone Severity Scale. 

Each hazard is assigned a category between 1 and 5 based on its estimated severity. If one hazard is higher than the others, the hurricane’s rating would be at least that category. 

As an example, if wind and storm surge are deemed a Category 2, but rainfall is a Category 3, the hurricane would be rated a Category 3. Under the scale, if multiple hazards are rated high enough, a hurricane can be considered a Category 6. 

Collins and her colleagues hope to convince leaders at the National Hurricane Center to implement their scale. “I know they have been interested in their products and how effective they are,” she said. 

“They have shown this in the last year or two,” Collins continued. “So I do think now’s the right time to be having that discussion with them.” 

For more information, read this article from USF News.