SOURCE: Truthdig

DATE: January 14, 2018

SNIP: New research has confirmed one of the worst nightmares of climate science: the instability of the East Antarctic ice sheet.

[R]esearchers have confirmed that one stretch of the southern polar coastline has melted many times in the past: by enough to raise sea levels by three to five metres.

US scientists report in the journal Nature that they went to what they called the Sabrina Coast of eastern Antarctica to look for geological and geophysical evidence of change.

Although the western region, and the Antarctic peninsula, is warming swiftly, for decades scientists have assumed that the great mass of ice in the eastern Antarctic was stable.

But last year a research team looked more closely at meltwater flow from one of the region’s glaciers and concluded that it was not stable, and that any melting could result in a dramatic rise in sea levels.

The latest study confirms that suspicion. “It turns out that for much of the East Antarctic Ice Sheet’s history, it was not the commonly perceived large stable ice sheet with only minor changes in size over millions of years,” said Sean Gulick, of the University of Texas Institute for Geophysics, one of those who led the study.

“Rather, we have evidence for a very dynamic ice sheet that grew and shrank significantly between glacial and interglacial periods. There were also often long intervals of open water along the Sabrina Coast, with limited glacial influence.”

And his co-author Amelia Shevenell from the University of South Florida said: “As ice melts, global sea levels rise. Most of Florida is at or several feet above sea level.