In 2002, NASA released dramatic images that showed a portion of Antarctica's Larsen B ice shelf collapse and disappear. Now, the space agency says what's left of the massive feature will be gone before the end of the decade.
As NPR's Christopher Joyce reported in March, climate change has been accelerating the pace of disintegration of the 625-square-mile, 1,600-foot-thick Larsen B.
Now, a team led by Ala Khazendar of NASA's Jet Propulsion Laboratory has found that the ice is melting so fast that the shelf will be gone before 2020.
"This ice shelf has existed for at least 10,000 years, and soon it will be gone," Khazendar says.
"What is really surprising about Larsen B is how quickly the changes are taking place," he says. "Change has been relentless."
"Ice shelves are the gatekeepers for glaciers flowing from Antarctica toward the ocean. Without them, glacial ice enters the ocean faster and accelerates the pace of global sea level rise. This study, the first to look comprehensively at the health of the Larsen B remnant and the glaciers that flow into it, has been published online in the journal Earth and Planetary Science Letters.
"Khazendar's team used data on ice surface elevations and bedrock depths from instrumented aircraft participating in NASA's Operation IceBridge, a multiyear airborne survey campaign that provides unprecedented documentation annually of Antarctica's glaciers, ice shelves and ice sheets. Data on flow speeds came from spaceborne synthetic aperture radars operating since 1997."