What was done
The author briefly reviews our knowledge of the West Antarctic Ice Sheet (WAIS) and analyzes its historical retreat in terms of both its grounding line and ice front.

What was learned
From the time of the Last Glacial Maximum to the present, the retreat of the WAIS's grounding line has been faster than that of its ice front, which has resulted in an expanding Ross Ice Shelf.  In fact, Bindschadler reports that "the ice front now appears to be nearly stable."  Nevertheless, the grounding line appears to be retreating at a rate that suggests complete dissolution of the WAIS in another 4,000 to 7,000 years.  Such a retreat would result in a sustained sea level rise of 8 to 13 cm per century.  However, even the smallest of these sea level rise rates would require "a large negative mass balance for all of West Antarctica," and there are as yet no broad-based data to support this scenario.

What it means
Although different portions of the WAIS display different grounding line retreat rates and local mass balances, all data considered together do not suggest any imminent change of a significant nature in response to the apparent warming of the planet over the last century.