Warmer seas give storms muscle

Tokyo – Warmer seas caused by climate change are making hurricanes stronger for longer after landfall, increasing the destruction they can wreak on impact, a new study has found.

Researchers warn the finding suggests inland communities – which may be less prepared than coastal regions to face hurricanes – are increasingly at risk.

The effects of climate change on tropical storms including hurricanes are still being studied, although the warming planet is already known to be making storms bigger and stronger.

So academics at a Japanese university looked at data on North Atlantic hurricanes from 19672018 and examined their “rate of decay” – how long they took to weaken – in the first day after landfall.

They sought to understand what impact warming seas might have on storms when they make landfall – typically when they begin to lose strength.

“We show that the decay time-scale has almost doubled in the past 50 years,” Pinaki Chakraborty, a professor at the Okinawa Institute of Science and Technology Graduate University who led the study, said.

That could mean destruction would “no longer be confined to coastal areas, causing higher levels of economic damage and costing more lives”, he warned.

The researchers looked to see whether the longer rate of decay correlated with sea temperatures, which vary year to year, though they are rising overall.

They found a clear link: when sea surface temperature was higher, storms stayed stronger on land for longer.

“Dry hurricanes” also lost intensity significantly faster, despite having developed over seas of differing temperatures.

Warming planet is already known to be making storms bigger and stronger.