🌀 Scientists propose addition of category 6 to hurricane scale

A team of scientists have proposed modifications to the Saffir-Simpson hurricane wind scale, which currently ends at category 5, to accommodate for increasingly severe tropical cyclones (TCs) resulting from global warming. The study, published in the Proceedings of the National Academy of Sciences (PNAS), suggests that the current category 5, which begins at wind speeds of 157mph, fails to adequately represent the wind risk in a warming world. The researchers propose extending the scale to a 6th category to communicate the significantly higher wind speeds of the most intense TCs caused by climate change.🌬️

The Saffir-Simpson scale, introduced in the 1970s, is the most widely used metric for public communication of wind hazard levels posed by storms. However, its open-ended nature means that the wind hazard level beyond category 5 remains constant, regardless of the storm's intensity. The scientists argue that this is a weakness of the scale, especially considering that the destructive potential of wind increases exponentially. They found that several recent storms have already reached what would be category 6 intensity, and more such storms are projected as the climate continues to warm. Over the past decade, at least five storms in the Western Pacific Ocean would have qualified for this new category, which would include all hurricanes with sustained winds of 192mph or more.🌊

While the number of hurricanes is not increasing due to climate change, the intensity of major storms has notably risen during the four-decade satellite record of hurricanes. A super-heated ocean is providing the energy to rapidly intensify hurricanes, aided by a warmer, moisture-laden atmosphere. The researchers argue that while the Saffir-Simpson scale is an imperfect measure of the dangers posed by a hurricane, a category 6 would highlight the heightened risks brought by the climate crisis. The primary purpose of this proposed change is to raise awareness about the impact of climate change on the intensity of storms.🔥