Antarctica Measurably Shrinking from Ice Melt

by Heidi Stevenson

22 November 2009

Until recently believed to be relatively stable and unlikely to melt significantly before the end of this century, scientists have found that Antarctica's ice sheet has melted significantly since 2006. Losing an estimated 190 billion tons of ice a year, it's feared that the southern ice sheet may soon melt faster than Greenland's, with major implications in rising sea levels.

Jianli Chen of the University of Texas at Austin stated, "If the current trend continues or gets worse, Antarctica could become the largest contributor to sea level rises in the world. It could start to lose more ice than Greenland within a few years." He and his team used data from Nasa's gravity recovery and climate experiment (Grace) to analyze variations in the earth's gravitational pull between April 2002 and January 2009. Changes in ice mass affect the earth's gravitational pull at the south pole.

Chen says that the increased ice melt may have been triggered by warmer ocean water seeping under the ice sheet, so that it slides faster. Increases in water under Greenland's ice is believed to be a significant factor in the rapidity of Greenland's ice melt.