The last large piece of ice of Antarctica’s Larsen B Ice Shelf, which partially collapsed in 2002, will disappear by the end of the decade, says a new NASA study.
The Larsen Ice Shelf is located in the northwest part of the Weddell Sea. Made up of three segments called Larsen A (the smallest), Larsen B, and Larsen C (the largest), the shelf extends along the east coast of the Antarctic Peninsula from Cape Longing to an area just southward of Hearst Island.
Led by Ala Khazendar of NASA’s Jet Propulsion Laboratory (JPL) in California, the research team found that the remnant of the Larsen B Ice Shelf is flowing faster, becoming increasingly fragmented and developing large cracks. Two of its tributary glaciers also are flowing faster and thinning rapidly.
Khazendar’s team gathered data on ice surface elevations and bedrock depths from instrumented aircraft participating in NASA’s Operation IceBridge: a multi-year airborne survey campaign that provides unprecedented annual documentation of Antarctica’s glaciers, ice shelves and ice sheets. Data about flow speeds was collected by spaceborne synthetic aperture radars that have been operating since 1997.
“What is really surprising about Larsen B is how quickly the changes are taking place,” commented Khazendar. “This ice shelf has existed for at least 10,000 years, and soon it will be gone.”
In 2002, daily tracking satellite images registered the collapse of a huge chunk of the Larsen B Ice Shelf in just a month. The area was similar in size to Rhode Island—1,250 square miles.
While some cases are more dramatic than others, ice melting in Antarctica is widespread. Despite the balance between the melting and replenishment of ice sheets by snow—over thousands of years—remaining stable, the system has drastically changed in the last two decades due to global warming. As a result of global warming, there is an increase in the amount of ice flowing into the ocean; with Antarctica currently losing 147 gigatons of ice each year.
– Antonio Sousa, Correspondent (Antarctica)