The EAIS is actually LOSING ice. Much to the surprise of climatologists. See ...
http://climateprogress.org/2009/11/23/satellite-data-grace-east-antarctica-ice-sheet-losing-mass/Climatologists had believed that because of global warming that Antarctica, and especially the EAIS, would actually GAIN ice for awhile due to increased snowfall caused by the increased evaporation by the warmer oceans.
However, reality is different. The Grace sattelite measures the amount of ice by measuring its gravity impact. More ice means more mass which means more gravity. And, less gravity means less ice. And the satellite is measuring the entire Antarctic mass, unlike coring or other land based measurements.
If the EAIS is losing ice, as well as the WAIS, the estimates for sea level rise this century may very well be greatly underestimated. The more the ice caps of Greenland and Antarctic are researched, the original idea that they are just big blocks of ice that will melt slowly is wrong.
Ice shelves can fail catastrophically. Ice rivers and sheets can begin to move much faster to the sea. Surface melt water will make crevasses through the ice and bring heat to within the ice cap itself. Water falling to the bottom of the ice cap will lubricate and float the ice cap above and bring it to the sea. Basically, we don't know how long it takes for an ice cap to disappear when climagte warming occurs.