Stalagmites reveal rapid sea level change

Ancient stalagmites from a submerged Italian cave have revealed sea level rises caused by global warming more than 200,000 years ago, according to a joint European-Australian study.

The finding, which appears in the journal Nature Geoscience, suggests the current melting of ice sheets may happen faster than expected.

Their publication adds weight to the release of an international report showing up to one-third of all Antarctic sea ice is likely to melt by the end of the century.

By comparing the dates of sea level rises with known increases in temperature, based on studies of ice cores from the Antarctic, they have shown the ice sheets respond rapidly to global warming.

It was previously believed that temperature rise preceded ice sheet melting by more than 3000 years.

“But these two variables have operated in phase for the major termination events in the past 500,000 years,” the researchers write in the paper.

Dutton says this suggests ice sheets are capable of responding quickly to increasing temperature and CO2.

That view appears to be supported by the Antarctic Climate Change and the Environment report released this week, which suggests sea temperatures in the Southern Ocean are rising faster than in other oceans.

ABC