Sunday, March 8, 2009

Scientists to issue stark warning over dramatic new sea level figures

Robin McKie in the Guardian (UK), with additional research by Lisa Kjellson: Scientists will warn this week that rising sea levels, triggered by global warming, pose a far greater danger to the planet than previously estimated. There is now a major risk that many coastal areas around the world will be inundated by the end of the century because Antarctic and Greenland ice sheets are melting faster than previously estimated.

Low-lying areas including Bangladesh, Florida, the Maldives and the Netherlands face catastrophic flooding, while, in Britain, large areas of the Norfolk Broads and the Thames estuary are likely to disappear by 2100. In addition, cities including London, Hull and Portsmouth will need new flood defences.

"It is now clear that there are going to be massive flooding disasters around the globe," said Dr David Vaughan, of the British Antarctic Survey. "Populations are shifting to the coast, which means that more and more people are going to be threatened by sea-level rises."

…From studying satellite images, scientists have watched the sea ice that hugs the Greenland and Antarctic shores dwindle and disappear. Sea-ice melting on its own does not cause ocean levels to rise, but its disappearance has a major impact on land ice sheets. Without sea ice to prop them up, the land sheets tip into the water and disintegrate at increasing rates, a phenomenon that is now being studied in detail by researchers.

"It is becoming increasingly apparent from our studies of Greenland and Antarctica that changes to sea ice are being transmitted into the hearts of the land-ice sheets in a remarkably short time," added Vaughan. As a result, those land sheets are breaking up faster and far more melt water is being added to the oceans than was previously expected….

Blue Lias cliffs at Lyme Regis, Dorset, UK

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