The risk of the Antarctic ice sheet collapsing and flooding coasts around the world has been exaggerated, according to researchers.
Previous studies had claimed that melting Antarctic ice could contribute one metre to the rising sea levels by the end of the century, flooding the homes of 150 million people and threatening dozens of coastal cities.
However, a team of British and French scientists has found that the collapse in the ice sheet is likely to raise sea levels by 10cm by 2100. An increase in sea levels from the ice sheet becoming unstable is “extremely unlikely to be higher than 30cm” this century, they say, describing previous, more apocalyptic predictions, as implausible.
The study, published in the journal Nature, found that there was a one in 20 chance that parts of the ice sheet breaking off could contribute more than 30cm to the sea level by the end of the century and more than 72cm by 2200.
The sea level has already risen by 19cm since 1901 and the annual rate has almost doubled since then to about 3.2mm a year, according to the Intergovernmental Panel on Climate Change.
The UN agency predicted in 2013 that sea levels would rise by about another 60cm by 2100. The panel was unable to calculate, and did not include in its prediction, the risk of substantial parts of the Antarctic ice sheet collapsing.
Some studies suggested that the risk was high and that the overall increase in the sea level would be well over a metre by 2100 once the collapse of the ice sheet was included.
Tamsin Edwards, an author of the new study — which involved scientists from the University of Bristol and Grenoble Alpes University — said that earlier reports were likely to be wrong because they were based on simpler computer models which contained many uncertainties.