Greenland melt speeding up

Greenland’s glaciers are dumping more than twice as much ice into the Atlantic Ocean now as 10 years ago because glaciers are sliding off the land more quickly, say researchers. This means oceans will rise even faster than forecast, the researchers report in last week’s issue of the journal Science.

Glaciers around the world are disappearing quickly, several researchers told a recent meeting of the American Association for the Advancement of Science, which publishes Science.

“Greenland is probably going to contribute more and faster to sea level rise than predicted,” Eric Rignot of NASA’s Jet Propulsion Laboratory at the California Institute of Technology told a news conference.

Between 1996 and 2006, the amount of water lost from Greenland’s ice sheet has more than doubled. One glacier that once was stable is now disappearing at the rate of 14 km a year. Greenland now contributes about half a millimeter to the annual 3 mm rise in global sea levels.

Rising air temperatures are clearly a factor, researchers told the meeting. Over the last 20 years, the air temperature in southeast Greenland has risen by 3°C. Warmer air lubricates the bottoms of glaciers, helping them slide faster.