The ice sheet of the West Antarctica had begun melting. This made the glacial region's loss of a major section "unstoppable," the National Aeronautics and Space Administration or NASA reported.

Recent findings, led by Glaciologist Eric Rignot of NASA's Jet Propulsion Laboratory, are a follow-up to decades of research, specifically that of Glaciologist John Mercer saying in his 1968 paper that the West Antarctic ice sheet was a "uniquely vulnerable and unstable body of ice." Most of West Antarctica's ice sheet is "grounded" on a bed that lies below sea level.

Mercer found unlike East Antarctica and Greenland, West Antarctica's ice had changed considerably many millennia ago. The Amundsen Sea region is a vulnerable area because its ice sheet is attached to a bed below sea level where warm water can be delivered by ocean currents to glacier grounding lines, the location where the ice attaches to the bed. This will then trigger a "Domino effect" reaction that will result in inland retreat, ice shelves loss of mass, glacier thinning and ultimately end in an increased ice flow to the sea and the rise of sea levels.

Using 40 years worth of data, the melting of the region is occurring in a rapid pace. While it could take several centuries, ABC News quoted University of Washington Glaciologist Ian Joughin stressing, "We really are witnessing the beginning stages."

Rignot provided a grim conclusion that the glaciers in the West Antarctica's Amundsen Sea sector "have passed the point of no return."

NASA estimated the glaciers in the Amundsen region contain enough ice to raise global sea levels by 4 feet (1.2 meters) while the entire West Antarctic ice sheet would raise global sea level by about 16 feet (5 meters).

To learn more, read NASA's The "Unstable" West Antarctic Ice Sheet: A Primer.