"'Lake E' has been a successful partnership in very challenging conditions. These results make a significant contribution to our understanding of how Earth's climate system works, and improve our understanding of what future climate might be like."
The scientists suspect the trigger for intense interglacials might lie in Antarctica.
Earlier work by the international ANDRILL program discovered recurring intervals when the West Antarctic Ice Sheet melted. (ANDRILL, or the ANtarctic geological DRILLing project, is a collaboration of scientists from five nations--Germany, Italy, New Zealand, the United Kingdom and the United States--to recover geologic records from the Antarctic margin.)
The current Lake E study shows that some of these events match with the super interglacials in the Arctic.
The results are of global significance, they believe, demonstrating strong indications of an ongoing collapse of ice shelves around the Antarctic Peninsula and at the margins of the West Antarctica Ice Sheet--and a potential acceleration in the near future.
The Science paper co-authors discuss two scenarios for future testing that could explain the Northern Hemisphere-Southern Hemisphere climate coupling.
First, they say, reduced glacial ice cover and loss of ice shelves in Antarctica could have limited formation of cold bottom water masses that flow into the North Pacific Ocean and upwell to the surface, resulting in warmer surface waters, higher temperatures and increased precipitation on land.
Alternatively, disintegration of the West Antarctic Ice Sheet may have led to significant global sea level rise and allowed more warm surface water to reach the Arctic Ocean through the Bering Strait.
Lake E's past, say the researchers, could be the key to our global climate future.
|Contact: Cheryl Dybas|
National Science Foundation