This year’s warm waters in the Gulf of Mexico helped Milton swiftly become a powerful hurricane, with the U.S. National Hurricane Center calling it the third-fastest intensifying Atlantic storm on record.
Milton’s rapid power surge appears to be the latest example of a worrying trend, scientists said, with climate change not only fuelling more powerful storms, but doing so more quickly.
Here is what you need to know:
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WHAT IS BEHIND A STORM’S STRENGTH?
As storm winds organize into a hurricane, they pull energy from the heat in surface waters. The warmer the water, the more fuel for a hurricane. Thanks to climate change, water temperatures are rising. In the last four decades, the ocean has absorbed about 90% of the warming from greenhouse gas emissions.
This year has seen especially warm waters due to climate change, with 2024 on track to have the warmest average global air temperature on record.
The past 12 months have seen global warming at 1.62 degrees Celsius (2.92 degrees Fahrenheit) above pre-industrial levels, the European Union’s Copernicus Climate Change Service said on Tuesday. A storm’s strength is defined by its sustained wind speeds, with a Category 1 hurricane carrying wind speeds of 74-95 mph (119-153 kph), while a dangerous Category 5 storm has wind speeds of 157 mph (252 kph) or higher.
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HOW IS STRENGTH DIFFERENT FROM INTENSIFICATION?
When a storm powers up quickly, scientists refer to its “rapid intensification.”
When a storm rapidly intensifies, sustained wind speeds increase by at least 35 mph (56 kph) within 24 hours, which can see a storm jump by two categories.
On Monday, Milton became the third-most rapidly intensifying Atlantic storm as its wind speeds increased by more than double the criteria for rapid intensification, shifting from a tropical storm to a Category 5 storm in less than a day.
The Gulf’s warm water, along with air conditions, made Milton’s rapid intensification “a near-certainty,” said physical oceanographer Gregory Foltz with the U.S. National Oceanic and Atmospheric Administration. A study last year suggested that storms originating in the Atlantic Ocean are now more than twice as likely to strengthen from Category 1 to Category 3 in just 36 hours, based on data from 2001-2020 compared with 1971-1990.
In mid-September, just weeks ahead of Milton’s formation, the Gulf was the warmest for that time of year on record.