The perfect storm: How climate crisis amplifies hurricanes

Back in May, the US National Oceanic and Atmospheric Administration (NOAA) predicted a "near normal" Atlantic hurricane season, which runs from June 1 to November 30.

That was in large part because of the El Nino global weather pattern, which causes a higher than average "vertical wind shear" in the Atlantic, which in turn suppresses hurricane activity.

"If you have big changes in the wind with height, that tends to import dry, lower-energy air into the core of a tropical cyclone and prevent it from strengthening," Allison Wing, an atmospheric scientist at Florida State University said.

But come August, NOAA increased its forecast prediction for the season to "above normal," based on ocean and atmospheric conditions "such as record-warm Atlantic sea surface temperatures" that "are likely to counterbalance the usually limiting atmospheric conditions associated with the ongoing El Nino event."

"It's been a sort of tricky year in terms of thinking about the whole seasonal forecast because we have these two opposing factors," said Wing.

What is known about the climate crisis

One-eye catching example: on July 24 a buoy off the southern tip of Florida recorded an alarming peak temperature of 101.1 degrees Fahrenheit (38.4 Celsius), readings more commonly associated with hot tubs and a possible new world record.

"Warm waters, both at the surface of the ocean and beneath, provide the fuel that intensifies tropical storms and hurricanes," said Michael Mann, a climatologist at the University of Pennsylvania. "That allows them to both intensify faster and attain higher maximum intensities."

You still need the right conditions to lead to hurricane formation - but when they come along, storms will take advantage of warming oceans to generate fiercer winds and cause bigger storm surges.

Apart from affecting the maximum intensity of hurricanes, the climate crisis can also increase the amount of rain they are able to dump, according to Andrew Kruczkiewicz, an atmospheric scientist and researcher at the International Research Institute for Climate and Society at Columbia University.

"The warmer the atmosphere is, the greater the capacity for water," he said. "This can mean increased intense precipitation events."

Last year, the climate crisis boosted Hurricane Ian's rainfall by at least 10 percent, according to recent research.

There's also increasing evidence that the storm season itself is getting longer, as the window during which ocean surface temperatures support tropical storm formation begins sooner and ends later, said Mann - a relationship that appears to hold true in both the Atlantic hurricane basin and the Bay of Bengal.