Are hurricanes getting worse? In a word: yes. While there’s no clear indication that hurricanes are happening more often than 40 years ago (when detailed satellite records began), evidence suggests they’re becoming more intense and destructive as Earth’s climate warms.
In 2022, a team of researchers found that extreme Atlantic hurricane seasons are twice as likely today compared to 40 years ago, partly due to rising sea surface temperatures, which provide more energy for storms to develop and strengthen.
A 2021 report from the Intergovernmental Panel on Climate Change notes that over the same period, storms in the North Atlantic have become more likely to develop into ‘major hurricanes’ (Category 3 or above) and to intensify more rapidly, making them harder to predict and prepare for.
Hurricanes are categorised on a scale of 1 to 5 based on their maximum sustained wind speed.
Category 5 storms, with winds above 262km/h (157mph), are the strongest, promising catastrophic damage. But the scale has been blasted as a poor encapsulation of the full destructive capacity of a storm.
‘Lesser’ hurricanes have often proved more devastating in terms of fatalities and cost.
Hurricane Katrina, for instance, which made landfall near New Orleans as a Category 3 storm in 2005, wrought most of its destruction with an extreme storm surge, which pushed large amounts of seawater onshore ahead of the storm.
The surge overwhelmed the city’s levees, flooded 80 per cent of its area and claimed more than 1,800 lives.
Researchers found that sea level rise due to climate change caused the New Orleans floods to climb up to 60 per cent higher than if the same storm had hit the region in 1900.
Meanwhile, our superheated atmosphere, which holds more moisture than it did before, is making hurricanes wetter, with extreme rainfall up by 11 per cent.
A study published in the journal Nature found that the speed that hurricanes track across Earth’s surface has slowed by 10 per cent in the past 70 years, too. That means a more prolonged onslaught of torrential rain for those living in a storm’s path.
For example, when Category 4 hurricane Harvey stalled over Houston in 2017, it dumped almost an entire year’s worth of rain in three days, prompting catastrophic floods and killing at least 37 of its residents.
While it’s difficult to attribute any one hurricane to climate change, the evidence is incontrovertible: in a warming world, hurricanes are becoming more intense, sustained, unpredictable and destructive.
In fact, despite the limitations of the wind-based category system, some experts are calling for a Category 6 to be added – to describe storms with wind speeds of more than 308km/h (192mph).
For the Atlantic hurricane season this year, the UK Met Office and NOAA’s National Hurricane Center are predicting an average of 11 hurricanes, including five of Category 3–5, which would make it one of the most active seasons on record (a typical year sees seven hurricanes, three of them major).
The busy forecast is the result of unprecedented sea surface temperatures, which have been shattering heat records since March 2023 and are currently running more than 2°C warmer than average.
This article is an answer to the question (asked by Jonny Adams, Peterborough) 'Are hurricanes getting worse?'
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