As hurricanes become increasingly powerful due to the climate crisis, scientists are urging for the expansion of the Saffir-Simpson hurricane scale to include a new category 6 designation, capable of encompassing storms with sustained winds exceeding 192mph.
Researchers, led by Michael Wehner of Lawrence Berkeley National Laboratory and James Kossin of the University of Wisconsin-Madison, have proposed this new classification in response to the escalating intensity of hurricanes fueled by global heating.
Published in the Proceedings of the National Academy of Sciences, the study argues that the existing scale, developed in the 1970s, fails to adequately capture the extreme ferocity of these mega-hurricanes, which pose unprecedented threats to life and property.
While hurricanes have traditionally been classified from category 1 to 5 based on wind speed, with category 5 representing the most severe storms exceeding 157mph, recent disasters such as Typhoon Haiyan and Hurricane Patricia have demonstrated the need for a higher classification.
Wehner emphasizes that the absence of category 6 storms in the Atlantic or Gulf of Mexico is merely a matter of luck, as these regions have the potential for such extreme events. He warns that climate change is driving the intensification of hurricanes, making the emergence of category 6 storms increasingly likely.
Although the total number of hurricanes has not increased, the study highlights a significant uptick in the intensity of major storms over the past four decades. This trend is attributed to warmer oceans providing additional energy for rapid hurricane intensification, exacerbated by a moist atmosphere.
While the Saffir-Simpson scale primarily assesses wind speed, Wehner acknowledges that the most severe threats from hurricanes often stem from heavy rainfall and coastal flooding. Nonetheless, the introduction of a category 6 designation aims to raise awareness of the heightened risks posed by climate change-induced storms.
As the world grapples with the growing impact of extreme weather events, the call for a new hurricane classification underscores the urgent need for action to mitigate the effects of the climate crisis on vulnerable communities worldwide.