Researchers from IVM design a new hurricane-classification system

Researchers Nadia Bloemendaal, Hans de Moel, Jantsje Mol and Priscilla Bosma from the Institute for Environmental Studies (IVM) have designed a new method to improve hurricane classification.

01/19/2021 | 11:50 AM

Together with colleagues from the University of South Florida they designed the Tropical Cyclone Severity Scale, which translates the total threat of a hurricane to a Category between 0 and 6, with a Category 6 reflecting an extremely severe hurricane. Their work has been published in Environmental Research Letters.

Currently, hurricanes are being classified on the Saffir-Simpson Hurricane Wind Scale, which categorizes a hurricane on a scale from 0 to 5 based on its maximum wind speed. However, extreme wind speeds are only one of three dangerous components of a hurricane: high storm surges and precipitation totals can have devastating consequences too. A good example of this is Hurricane Harvey in 2017, which dropped over 1.5 meters of rainfall over the greater Houston Area – an absolute record. This exposes the weakness of the Saffir-Simpson scale: people may mistakenly perceive a low-category hurricane on the Saffir-Simpson scale as a low-risk hurricane, which may lead them to think evacuation is not necessary. On the Tropical Cyclone Severity Scale, Hurricane Harvey would have classified as a Category 5, thus better reflecting the true severity of this hurricane.