A new study suggests that the escalating severity of hurricanes due to the climate crisis necessitates the addition of a “category 6” to the existing 1 to 5 scale of hurricane classification. According to the researchers, this new category would encompass hurricanes with sustained winds exceeding 192mph, a benchmark that five storms over the past decade have already met. The proposal for this expansion comes from Michael Wehner of the Lawrence Berkeley National Laboratory and James Kossin of the University of Wisconsin-Madison, who argue that the increasing likelihood of such mega-hurricanes is a consequence of ocean and atmospheric warming.
Wehner expressed the severity of such storms, stating, “192mph is probably faster than most Ferraris, it’s hard to even imagine”. He further emphasized the dire situation of experiencing such a hurricane, saying, “Being caught in that sort of hurricane would be bad. Very bad.”
The call for a new hurricane category is based on findings published in the Proceedings of the National Academy of Sciences and aims to modify the Saffir-Simpson hurricane scale, which was developed in the early 1970s. The current scale, which deems any hurricane with sustained winds of 74mph or higher as a Category 1 event and classifies storms with speeds of 157mph and above as Category 5, has been a standard for assessing hurricane intensity. However, the study highlights that recent years have witnessed storms of such extraordinary intensity that they warrant the creation of an additional category.
Notable storms that would fit into this proposed category 6 include Typhoon Haiyan and Hurricane Patricia, with Patricia reaching wind speeds of 215mph. Wehner noted the absence of such hurricanes in the Atlantic or the Gulf of Mexico, attributing it to luck and expressing concern over the potential occurrence of such extreme events in the future. “There haven’t been any in the Atlantic or the Gulf of Mexico yet but they have conditions conducive to a category 6, it’s just luck that there hasn’t been one yet,” he said, adding, “I hope it won’t happen, but it’s just a roll of the dice. We know that these storms have already gotten more intense, and will continue to do so.”
The study points out that while the overall number of hurricanes may not be increasing, the intensity of major storms has risen significantly over the past four decades, driven by a warmer, more energized ocean and a moisture-rich atmosphere. The researchers believe that while the Saffir-Simpson scale primarily measures wind speed, the introduction of a category 6 would underscore the escalating risks posed by severe rainfall and coastal flooding due to climate change. Wehner stated, “Our main purpose is to raise awareness that climate change is affecting the most intense storms,” highlighting the primary objective behind proposing the new category.
