The “Doomsday Glacier” Is Barely Hanging On

A study published Monday in the journal Nature Geoscience found that Antarctica’s Thwaites Glacier, nicknamed the “doomsday glacier” due to the fact that its melting could drastically raise sea levels, is retreating more slowly than it did 100 years ago, and the authors say that’s both good and bad news.

“About 100 years ago, it retreated faster than it is currently retreating… you could say that’s good news because it’s not so bad now compared to what it was in the past,” said study co-author Anna Wåhlin to NBC News. “But you can also say that it’s bad news, because it could happen again.”

Scientists were previously only able to look back at a 30-year satellite history of the glacier’s movements, but these most recent findings examined the imprints the glacier made on the seabed to look back approx 100 years. They found that a century ago, the glacier was melting twice as fast as it is now, receding at an astonishing 1.3 miles per year.

The study also found that the glacier is eroding on its underside and that the base of the glacier detached from the seabed at some point in time. Another study’s co-author, marine geophysicist Robert Larter, says this doesn’t bode well for the future of the glacier, explaining, “Thwaites is really holding on today by its fingernails, and we should expect to see big changes over small timescales in the future—even from one year to the next—once the glacier retreats beyond a shallow ridge in its bed.”

The scientists said they hope to return to the glacier to do more studies that will help them predict future changes in its ice mass.