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‘Global warming not to blame for floods’

  • The exceptional high tide at St George (Photograph supplied)

Global warming is not to blame for recent flooding and high tides in Bermuda, an oceanographer said yesterday.

Ruth Curry, physical oceanographer at the Bermuda Institute of Ocean Sciences, said that two factors were responsible for the high water that submerged low-lying portions of the island over the weekend, including King’s Square in St George.

Ms Curry said the recent full moon, coupled with a warm ocean eddy passing Bermuda, was to blame. She added: “This is no a consequence of global warming, but is a very unususal phenomenon.”

James Dodgson, director of the Bermuda Weather Service, agreed.

He said: “There is no current evidence that this is driven by global warming or climate change.”

Because of the full moon, the tide over the past couple of days was predicted to be slightly higher.

Ms Curry explained the phenomenon is called a king tide. She said that Bermuda was also experiencing the effects of higher sea levels associated with a warm eddy.

Mr Dodgson said: “Predicted high tides have been nearly 1ft higher than they naturally can be at other times of the year, and the sea height anomoly is hovering around 1ft.“This equates to a water level perhaps 2ft higher at high tide than at other times of the year.” Ms Curry said eddies are “ubiquitous ocean features that have circular structure and trap and transport waters coherently around the ocean over long distances”.

Depending on where an eddy forms, the water in it can be either warmer or colder than the water outside it and regularly pass Bermuda.

She added: “The volume of water expands when it is warmed and shrinks when it is cooled.

“The sea surface will exhibit a slight bulge where the underlying waters are warm, or a depression if the waters are cold.”

The Gulf Stream is a major source of cold eddies, while the warm eddies that flow past Bermuda often originate to the south and east of the island.

Ms Curry said Bermuda is on the western edge of a warm eddy. She added that “several very strong cyclonic eddies” are sitting east of the island and poised to head towards the island.

Ms Curry said: “Bermudians can expect the effects of this warm eddy to persist for another few weeks, followed by very strong currents and a lowering of the water level as the cold eddy approaches.

“Water levels will be higher than average, but the tidal effects will subside shortly.

“Hopefully, the flooding will cease as well.”

Mr Dodgson added: “General water recession at high tide can be expected in the coming days as the predicted high-tide levels gradually fall.”