In recent years, hurricanes have been intensifying as the world warms, prompting scientists to suggest the need for a sixth category of hurricanes. The current classification system of hurricanes being categorized on a scale of one to five is no longer sufficient to capture the increasing intensity of these storms, say researchers Michael Wehner and James Kossin.
Category 5 hurricanes already have no upper limit on the Saffir–Simpson intensity scale. These hurricanes have wind speeds exceeding about 70 meters per second and cause catastrophic destruction. Storms like Hurricane Katrina in 2005 and Hurricane Maria in 2017, both classified as Category 5 hurricanes, have caused significant devastation and loss of life.
Over the past four decades, there has been an increase in the number of Category 5 hurricanes, with more than half occurring in the last 17 years. The most destructive storms have occurred in the last nine years, with wind speeds exceeding 80 meters per second in some cases. These storms have caused widespread destruction and loss of life, highlighting the need for an additional category to capture their intensity.
Researchers Wehner and Kossin propose that a sixth category be added to the classification system based on weather models and observations from the past four decades. This new category would reflect the increasing frequency and intensity of Category 5 hurricanes.
Storms like Haiyan in the Philippines in 2013 and Patricia in Mexico in 2015 have demonstrated the devastating impact of Category 5 hurricanes. The proposal for a new category is based on the observation of storms that have already crossed the threshold for Category 6 intensity. As these storms continue to increase in frequency and intensity, it is essential to have a classification system that accurately reflects their destructive potential.
Weather models predict that Category 6 hurricanes will become more common as global temperatures continue to rise. Researchers estimate that at least one Category 6 hurricane could occur each year by mid-century if greenhouse gas emissions are not reduced.
The proposed new category would be defined by wind speeds exceeding about 93 meters per second (about 348 feet per second). This would place them among some of the strongest natural forces on Earth.
The need for a new category comes as scientists warn that climate change is causing more frequent and intense extreme weather events such as heatwaves, droughts, floods, wildfires, tornadoes, cyclones (tropical cyclones), thunderstorms and hailstorms around world
