As Hurricane Laura pounds the U.S. Gulf Coast with nearly 150 mile-per-hour winds, causing water levels to rise almost 10 feet above normal, wildfires in California are still raging across more than a million acres, the result of a heatwave that spiked as high as 130° Fahrenheit (54.4° Celsius)—possibly the hottest temperature ever sustained on Earth. In the middle of the country, an inland hurricane flattened a large part of Iowa and darkened Chicago homes. And a tropical storm left thousands in New York without electricity for a week or more. That was just some of the extreme weather the U.S. suffered this month.
Extreme weather events will only get more frequent as warming continues—not heading toward a new, stable level of activity, but rather tipping further into chaos, said Kevin Trenberth, a climate scientist who recently retired from the National Center for Atmospheric Research. “There is no new normal,” he said. “Or if there is, it is temporary before further changes come along.”
The field of climate attribution is still relatively young, having started up in earnest only in 2004, the year after a European heatwave killed 70,000 people. But the science has progressed rapidly. Heatwaves in particular are less and less interesting for researchers. Friederike Otto, a University of Oxford climate researcher and organizer of the World Weather Attribution initiative, said she doesn’t think they’ll bother investigating the recent California heat from a climate change perspective. “The evidence is so strong already,” she said.
Hurricane Laura, meanwhile, is just the latest product of an Atlantic hurricane season that has generated storms at a record clip. Never before have seven hurricanes or tropical storms struck the U.S. by the end of August, according to Phil Klotzbach, lead author of the Colorado State University seasonal hurricane forecast, one of the gold standards of storm modeling. The Atlantic has had active storm years before, but hurricanes draw their strength from warm water, and researchers have long warned that increased global temperatures will lead to more powerful storms.