WASHINGTON, United States (AFP) — From Hurricane “Helene” to typhoon “Yagi,” powerful storms are battering the globe, and scientists warn that a warming planet is amplifying their destructive force to unprecedented levels.
Here’s what the latest research reveals about how climate change is supercharging tropical cyclones — the generic term for both weather phenomenon.
Packing more punch
First, the basics: warmer ocean surfaces release more water vapor, providing additional energy for storms, which intensifies their winds. A warming atmosphere also allows them to hold more water, boosting heavy rainfall.
“On average, the destructive potential of hurricanes has increased about 40 percent due to the 1 degrees Celsius (roughly 2 degrees Fahrenheit) warming that has already taken place,” Michael Mann, a climatologist at University of Pennsylvania, told Agence France-Presse (AFP).
In a recent paper in the Proceedings of the National Academy of Sciences, Mann added his voice to calls for the Saffir-Simpson scale to be expanded to include a “new class of monster storms” — Category 6, where sustained winds exceed 308 kilometers per hour.
According to experts, climate change set the stage for “Helene,” which peaked as a Category 4 hurricane.
“The oceanic heat content was at a record level, providing plenty of fuel and potential for a storm like this to gain strength and become a large and very damaging storm,” David Zierden, Florida’s state climatologist, told AFP.
Rapid intensification
“Rapid intensification,” defined as a hurricane speeding up by 30 knots within a 24-hour period, is also becoming more common.
“If intensification happens very close to the coast in the lead up to landfall, it can have a huge effect, which you saw last week in the case of Helene,” Karthik Balaguru, a climate scientist at the Department of Energy’s Pacific Northwest National Laboratory, told AFP.
Balaguru was the lead author on a paper this year in journal Earth’s Future that used decades of satellite data to show “a robust increase in the rates at which storms intensified close to the coast, and this is across the world.”