(Austin, Texas)  The West Antarctic ice sheet may not be shedding mass as fast as once thought.

  That's according to scientists who say new ground measurements suggest that the rate of ice loss on the sheet may have been previously overestimated a bit.

  But that doesn't mean West Antarctica isn't losing significant amounts of ice from melting, claim the researchers - from the University of Texas at Austin, Ohio State University and University of Memphis. They say while there's little doubt that sheet melting is contributing to rising sea levels, what remains uncertain is the rate.

  The experts theorize Antarctica was once buried under a deeper and more extensive layer of ice during a period known as the Last Glacial Maximum. Starting about 20 thousand years ago, the ice began to slowly thin and retreat.

  As the ice mass decreased, the bedrock immediately below the ice began to rise - an uplift known as post-glacial rebound, the scientists explain. The research appears in the electronic journal Geochemistry, Geophysics, Geosystems of the American Geophysical Union and the American Geochemical Society.



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