A new federal study concludes that human-caused climate change is supercharging hurricanes, making them larger and more intense.
The study, published Monday and conducted by researchers at the National Oceanic and Atmospheric Administration and the University of Wisconsin at Madison, analyzed satellite data over the last 40 years and found that planetary warming during that period increased the likelihood of a tropical cyclone become a major hurricane ― Category 3 strength or higher ― by approximately 8% per decade.
Scientists have long warned that hurricanes and other extreme weather will worsen alongside global warming. The 2015 National Climate Assessment, a congressionally mandated report conducted every four years, concluded that “hurricane intensity and rainfall are projected to increase as the climate continues to warm.” And research also shows there’s been a marked slowdown in hurricanes’ speed over both water and land, leading to increased risk of torrential rain, flooding and storm surge.
But the new analysis is perhaps the clearest evidence to date that the crisis is already intensifying tropical storm systems.
“The trend is there and it is real,” James P. Kossin, a NOAA researcher and lead author of the study, told The New York Times. “There’s this remarkable building of this body of evidence that we’re making these storms more deleterious.”
The report comes on the heels of a 2019 Atlantic hurricane season that tied 1969 as the fourth most active season on record, with 18 named storms, six hurricanes and three major hurricanes. Among them was Hurricane Dorian, a monster Category 5 storm that devastated the northern Bahamas and which climate scientists called “a preview of the climate crisis to come.”
Experts are warning of more of the same this year. The majority of organizations that have released 2020 seasonal forecasts predict above-average hurricane activity in the Atlantic, as CNN reported earlier this month. Penn State University, for example, predicts between 15 and 24 named tropical storms, in part due to warmer-than-normal water temperatures in the North Atlantic.
The NOAA is set to announce its outlook for the Atlantic hurricane season on Thursday as much of the nation reels from the ongoing COVID-19 pandemic. The official hurricane season runs from June 1 to Nov. 30, but it got an early start over the weekend when Tropical Storm Arthur ― the first named storm of the year ― formed off the coast of Florida. The system brushed the North Carolina coast on Monday, delivering heavy rain to parts of the state, before moving back out to sea.
In the past, President Donald Trump has marveled at the size and ferocity of hurricanes, including Harvey and Irma, only to scoff at the idea that climate change played a role. Former Environmental Protection Agency Administrator Scott Pruitt went as far as to call it “insensitive” to mention the climate crisis as storms were unfolding ― part of a well-documented effort by Trump and his team to bury and downplay climate science.