New study suggests climate link between Arctic and Antarctica

Posted on June 25, 2012 by Bob Berwyn

Sediment core record from remote Siberian lake shows unusually warm Arctic periods coincided with deglaciation of West Antarctica

Sea ice is vanishing around the Antarctic Peninsula, and there are signs the West Antarctic ice sheet may be prone to disintegration. Photo by Bob Berwyn.

Rifts along the northern shear margin of Pine Island Glacier (upper right of image). Photo courtesy Michael Studinger, NASA’s Operation IceBridge.

By Bob Berwyn

SUMMIT COUNTY — Researchers studying sediment cores dating back nearly 3 million years found evidence that the Arctic has experienced several intensely warm climate intervals, and that there may be a link between those periods and episodes of dramatic changes in the West Antarctic ice sheet.

“We found eight warm intervals … the majority relatively early in the Quarternary, when temperatures were 4 to 5 degrees Celsius warmer — as well as wetter — than during normal interglacial periods. They occurred irregularly, not following orbital cycles,” said Professor Martin Melles, of the University of Cologne, one of the lead researchers.

Other lead scientists include Julie Brigham-Grette of the University of Massachusetts Amherst; and Pavel Minyuk of Russia’s North-East Interdisciplinary Scientific Research Institute in Magadan.

“That’s what we know. Then we wanted to know the reasons for that. It can’t be explained by greenhouse gas variations or orbital variations, so we compared the interglacial warm intervals with other records,” said Melles, explaining that the warm intervals seemed to match up well with an Antarctic sediment core showing that the West Antarctic ice sheet disintegrated approximately during these same periods. (more…)

Filed under: climate and weather, Environment, global warming | Tagged: , , , , , | Leave a Comment »

Follow

Get every new post delivered to your Inbox.

Join 5,597 other followers