Antarctic glacial ice loss unprecedented

HOUSTON, Nov. 10 (UPI) -- U.S. and British scientists say the current warming and widespread loss of glacial ice on the Antarctic Peninsula is unprecedented.

"At no time during the last 14,000 years was there a period of climate warming and loss of ice as large and regionally synchronous as that we are now witnessing in the Antarctic Peninsula," said Steve Bohaty of Britain's National Oceanography Center.

Bohaty said the findings are based on a detailed analysis of the thickest Holocene sediment core yet drilled in the Antarctic Peninsula.

As part of a 2005 research cruise aboard a U.S. icebreaker, he and his colleagues drilled through sediments to bedrock at Maxwell Bay, a fjord at the Antarctic Peninsula's northwest tip.

The scientists determined there was a period of rapid glacial retreat about 10,000 years ago, followed by reduced sea-ice cover and warm water conditions between 8,200 and 5,900 years ago. But the researchers said an important finding of the study is that the mid-Holocene warming interval does not appear to have occurred synchronously throughout the region, and its timing and duration was most likely influenced at different sites by local oceanographic controls, as well as physical geography.

Following the warming interval, the climate gradually cooled during approximately the next 3,000 years or so, resulting in more extensive sea-ice cover in the bay

The core also showed the Antarctic Peninsula area has been warming during the last 50 years, with increased rainfall and a widespread retreat of glaciers.

The study that included scientists from Rice University, the University of Houston and Vermont's Middleburg College appears in the Geological Society of America Bulletin.