Scientists say climate change boosted Milton rainfall and winds

The devastating winds and torrential rains that Hurricane Milton delivered to Florida were made far worse by human-induced climate change, a team of international researchers reported on Friday.

Record-high global temperatures, boosted by the burning of fossil fuels, helped power the storm as it traveled across the balmy waters of the Gulf of Mexico, according to the World Weather Attribution group’s analysis released Friday morning. Those conditions boosted Milton’s rainfall between 20 to 30 percent and wind speed by 10 percent compared with a scenario without human-caused climate change.

“[T]he results are compatible with those obtained for other hurricanes in the area that have been studied in the scientific literature,” the researchers wrote. “We are therefore confident that such changes in heavy rainfall are attributable to human-caused climate change.”

The type of torrential rainfall from storms like Milton was twice as likely because of the 1.3 degrees Celsius (2.3 degrees Fahrenheit) of warming the world has experienced since the middle of the 19th century, WWA said. Milton delivered nearly 19 inches of rain in St. Petersburg, causing what meteorologists described as a 1-in-500-year flood in the city that sits on a peninsula at the mouth of Tampa Bay.

The findings come just days after the same research group found climate change also intensified Hurricane Helene, which like Milton intensified rapidly as it barreled toward the U.S. coast. Helene was the deadliest storm since 2017, killing more than 230 people across six states.

Attribution science, as the discipline is known, has matured in recent years and gained wider acceptance among the scientific community, according to the National Climate Assessment , a federal governmentwide anthology of climate science and impacts. The group’s findings on Helene and Milton back up broader research by scientists that suggest a hotter planet will fuel more intense cyclones whenever they form.

Despite the growing body of science showing the effects climate change is having on making hurricanes more powerful, skepticism remains among many politicians, such as Republican Florida Gov. Ron Desantis, who has downplayed climate change and dismissed any link to the storm this week, saying, “It is hurricane season.”

Those remarks came after Georgia Rep. Marjorie Taylor Greene , another Republican, drew ridicule from members of both parties for her post on X saying, “ Yes they can control the weather .” She added, “It’s ridiculous for anyone to lie and say it can’t be done.”

The team of researchers and scientists at the WWA compare and model extreme weather against a scenario in which no human-driven warming existed to determine how climate change influences those events.

Many of the conditions that sparked Helene remained in place for Milton, the researchers said. Climate change made the abnormally warm Gulf of Mexico waters that served as an engine for the rapid intensification of both cyclones 400 to 800 times more likely. Milton’s ascension over two days from tropical depression to Category 5 hurricane, with wind speeds clocking up to 180 mph, was particularly fast.

The group acknowledged some limitations in the quick analysis just a day after Milton made landfall. The researchers said not all observation-based datasets were updated and could not “reliably estimate how rare the heavy rainfall in the path of Milton was.” It also did not use climate models as it did for Helene.

The researchers instead relied on assessing trends in observed data, where in 3 of 4 datasets they found heavy one-day rainfall events like Milton are twice as likely with 1.3 degrees Celsius of warming and 20 to 30 percent more intense. The fourth dataset conveyed larger changes.

That the hurricanes made landfall just two weeks apart highlights the growing concern among emergency managers and climate scientists that compounding events driven by a turbocharged atmosphere are straining disaster response capacity .

The Federal Emergency Management Agency has said it was able respond to both Helene and Milton simultaneously, though the agency spent nearly half the disaster relief in eight days that Congress has allocated for the next 12 months.

Helene slammed an inland area of the Southeast largely unaccustomed to hurricanes, worsening its impact as it washed away roads and destroyed scores of homes. Milton killed comparatively fewer people, but its full toll is not yet known.

“Both the rapid intensification and the fact that emergency personnel were still continuing with the recovery from Helene made preparations difficult,” the WWA analysis said.

The Biden administration in August informed Congress the fund would need more appropriations to carry out fiscal year 2025 obligations, though lawmakers are not expected to take up any new funding measures until after the election.

Another blow would strain the coffers — and weeks of hurricane season remain.

While forecasts by the National Oceanic and Atmospheric Administration that 2024 would be the most active hurricane season in decades did not materialize as expected, the recent hurricanes have brought tremendous devastation and sizable financial losses. AccuWeather estimated between $160 billion and $180 billion of damage and economic loss from Milton, and $225 billion to $250 billion for Helene.