Mega-melt: Antarctica’s ice loss worse than ever

Low-lying communities may have less time to prepare for the potentially devastating effects climate change is having on rising sea levels, a new report on Antarctica’s rapidly melting ice sheet found.

The rate at which the ice is melting has tripled since 1992, resulting in more than 200 billion tons crashing into the ocean each year, raising sea levels by a half a millimeter annually.

If the current rate increase continues, we have about a decade to reduce greenhouse gas emissions enough to avoid losing entire cities to the sea, the report’s team of 80 scientists concluded.

“We took all the estimates across all the different techniques, and we got this consensus,” Isabella Velicogna, Antarctica expert at the University of California, Irvine, told The Washington Post.

The study, titled “Ice Sheet Mass Balance Inter-comparison Exercise ,” was published Wednesday in the journal Nature by authors from 14 nations.

From 1992 to 1997, Antarctica lost 49 billion tons of ice each year. In 2008, the rate climbed to 73 billion tons per year. And from 2012 through 2017, the continent — the world’s largest ice sheet — lost 219 billion tons of ice every year. The rate is triple what it was a decade ago, leeching Antarctica of nearly 3 trillion tons of ice since 1992.

“The detailed record shows an acceleration, starting around 2002,” said Beata Csatho, a co-author of the study, and a glaciologist at the University at Buffalo. “Actually, if you compare 1997-2002 to 20122017, the increase is even larger, a factor of more than five!”

The amount of ice that has melted into the sea equates to almost 8 millimeters of ocean level rise. Most of the depleted ice has been liquefied on the West Antarctic sheet which sits above the east coast of the United States. And, as Antarctica shrinks, its gravitational pull on the surrounding ocean releases, allowing the water to pool elsewhere — like U.S. coastal cities.

The West Antarctic lost 159 billion tons of ice each year on its own between 2012 and 2017 — more than 72% of the entire Antarctic ice sheet.