NASA: Antarctic ice shelf years from disintegration

The last intact section of one ofAntarctica's mammoth ice shelves is weakening fast and will likely disintegrate completely in the next few years, contributing further to rising sea levels, according to a NASA study released on Thursday.

The research focused on a remnant of the so-called Larsen B Ice Shelf, which has existed for at least 10,000 years but partially collapsed in 2002. What is left covers about 625 square miles (1,600 square km), about half the size of Rhode Island.

Antarcticahas dozens of ice shelves - massive, glacier-fed floating platforms of ice that hang over the sea at the edge of the continent's coast line. The largest is roughly the size ofFrance.

Larsen B is located in theAntarcticPeninsula, which extends toward the southern tip ofSouth Americaand is one of two principal areas of the continent where scientists have documented the thining of such ice formations.

"This study of theAntarcticPeninsula glaciers provides insights about how ice shelves farther south, which hold much more land ice, will react to a warming climate," said Eric Rignot, co-author of the study and a glaciologist at NASA's Jet Propulsion Laboratory inPasadena,California.

The UN Intergovernmental Panel on Climate Change has cited a probability of at least 95 percent that accelerated warming of the planet has been triggered by human activities.

The study, published online in the journal Earth and Planetary Science Letters, was based on airborne surveys and radar data.

The study's lead scientist,Ala Khazendar, said analysis of the data reveals that a widening rift in Larsen B will eventually break it apart completely, probably around the year 2020.

Once that happens, glaciers held in place by the ice shelf will slip into the ocean at a faster rate and contribute to rising sea levels, scientists say.