Huge ice shelf in Antarctica to collapse by 2020

Doyle Rice | USA TODAY

Show Caption Hide Caption Huge ice shelf in Antarctica to collapse by 2020 The last remaining section of Antarctica's Larsen B ice shelf, is quickly weakening and likely to disintegrate completely by 2020, according to a new study.



The last remaining section of Antarctica's Larsen B ice shelf, which partially collapsed in 2002, is quickly weakening and likely to disintegrate completely by 2020, said a new study out today.

Ice shelves are permanent floating sheets of ice that connect to a landmass, such as Antarctica, according to the National Snow and Ice Data Center.

When it goes, the ice shelf will shatter into hundreds of icebergs. Since it's already floating ice, the collapse of the ice shelf will not directly contribute to global sea-level rise.

However, ice shelves are the gatekeepers for glaciers flowing from Antarctica toward the ocean, according to NASA. Without them, glacial ice enters the ocean faster and accelerates the pace of global sea level rise.

The remaining section of the Larsen B ice shelf is roughly the size of 27 Manhattan islands.

"These are warning signs that the remnant is disintegrating," said study lead author Ala Khazendar of NASA's Jet Propulsion Laboratory, in a statement.

"Although it's fascinating scientifically to have a front-row seat to watch the ice shelf becoming unstable and breaking up, it's bad news for our planet," he said. "This ice shelf has existed for at least 10,000 years, and soon it will be gone."

The Larsen B Ice Shelf is on the eastern side of the Antarctic Peninsula, the part that looks like an arm reaching out toward South America. The peninsula has warmed 4.5 degrees Fahrenheit since 1950, making it one of the fastest-warming places on Earth.

Scientists think that the recent ice shelf collapses in both the Arctic and Antarctica are related to climate change.

Ice shelves are different from ice sheets. An ice sheet, which covers more than 97% of Antarctica, has built up over thousands of years as snow falls but never melts. As ice piles up, it slides slowly toward the continent's edge to form ice shelves attached to the ice sheet, but are floating in the ocean.

"This is certainly a warning," said Khazendar.

The study appeared in the journal Earth and Planetary Science Letters, and was written by researchers from NASA and the University of California at Irvine.