A. 3 to 5 feet — contributing to an increasingly likely total
sea level rise of more than 5 feet by 2100, a rise that will be
all but impossible to stop if we don’t sharply reverse CO2
emissions trends within a decade or so. West Antarctica’s
collapsing ice shelves are in the news today. This post will
survey what we now know about this unstable ice sheet and the
threat it poses to humanity — or is that the threat humanity
poses to it? — if we continue on our current suicidal emissions
path. Antarctica is disintegrating much faster than almost
anybody imagined. In 2001, the IPCC “consensus” said neither
Greenland nor Antarctica would lose significant mass by 2100.
They both already are. As Penn State climatologist Richard Alley
said in March 2006, the ice sheets appear to be shrinking “100
years ahead of schedule.” A 2007 study found “The current loss
of mass from the Amundsen Sea embayment of the West Antarctic
ice sheet [WAIS] is equivalent to that from the entire Greenland
ice sheet” (see the new survey re