A new study reveals that human-caused climate change significantly boosted the devastating impacts of Hurricanes Helene and Milton, foreshadowing the intensifying storms we’ll face in the future. The research finds that climate change increased Helene’s rainfall by 10% and wind speeds by 11%, while also making the extreme conditions that fueled the storm 200-500 times more likely. As the planet continues to warm, scientists warn that such ‘unimaginable’ hurricanes will become increasingly common, highlighting the urgent need for improved emergency preparedness and a transition away from fossil fuels. Hurricane Helene, Hurricane Milton
Hurricanes Intensified by Climate Change
The new study, conducted by the World Weather Attribution (WWA) collaborative, found that human-caused climate change significantly amplified the destructive power of Hurricane Helene, which struck the southeastern United States in 2024. The researchers determined that Helene’s rainfall was boosted by about 10%, while its wind speeds were increased by around 11%.
According to the analysis, the warming climate also made the extreme conditions that fueled Helene’s intensity 200 to 500 times more likely. This included warmer ocean temperatures in the Gulf of Mexico, which were about 3.6°F (2°C) above average. “When you start talking about the volumes involved, when you add even just a few percent on top of that, it makes it even much more destructive,” said study co-author Ben Clarke, a climate researcher at Imperial College London.
Hurricanes of the Future: More Frequent and Catastrophic
The scientists warned that the trends observed with Helene are likely to continue, with Hurricane Milton, which threatened the Florida coast just two weeks later, also expected to be similarly amplified by climate change. “Going forward, additional warming that we know will occur over the next 10 or 20 years will even worsen the statistics of hurricanes,” said Kim Cobb, director of the Institute at Brown for Environment and Society, who was not involved in the study.
Indeed, the researchers calculated that hurricanes as intense as Helene, which was the deadliest to hit the mainland U.S. since Hurricane Katrina in 2005, are now about 2.5 times more likely in the region compared to a world without climate change. “As we go into the future and our results show this as well, we still have control over what trajectory this goes in as to what risks we face in the future, what costs we pay in the future,” said Clarke. “That just hinges on how we change our energy systems and how many more fossil fuels we burn.”
Preparing for the Storms Ahead
The devastating impacts of Hurricanes Helene and Milton serve as a stark wake-up call, highlighting the urgent need for improved emergency preparedness and resilience planning in the face of the climate crisis. According to the study, many of those who died in Helene fell victim to the massive inland flooding, rather than just the high winds.
Cobb emphasizes that these powerful storms should motivate a significant shift in how we approach the challenge of climate change, both in terms of reducing fossil fuel emissions and adapting to the new normal of more frequent and extreme weather events. “Helene and Milton should serve as a wake up call” for taking action, she said, “for emergency preparedness, resilience planning and the increased use of fossil fuels.”
