There are 2 main ways floating ice sheets melt, from warm air above and from warm ocean currents attacking the underside of the sheets.  Results of a recent study using NASA’s Ice, Cloud, & Land Elevation Satellite indicate the warm ocean current process has been the main culprit in recent years. 

A group of international scientists conducted the study from 2003 to 2008 using the special NASA satellite with lasar altimetry and specialized computer models to process melt and runoff data.   It showed 20 of 54 ice shelves in Antarctica showed substantial melting from below due to warm water currents eating into them.  Many of these are on the west side of Antarctica. 

This new satellite altimetry technology, combined with information from aircraft,  satellite radar, and other projects will give researchers the best view yet of how the ice and oceans of the world are changing.  Numerous climate models predict that sea level could rise anywhere from 6 to 18″ on average worldwide in the next 50 years.  Some project an even more extreme rise.

You can read the full article here.   http://www.nasa.gov/topics/earth/features/currents-ice-loss.html

Posted under AGW, Arctic climate, Climate Change, World Weather