Antarctic Ice Can Melt 20 Times Faster Than We Thought

Melting ice sheets in Antarctica can retreat much faster than scientists previously thought.

A study published April 5 in the journal Nature found that at the end of the last Ice Age, parts of the Eurasian Ice Sheet retreated up to 2,000 feet per day.

The new findings could be crucial to better understanding today’s ice melt.

The Eurasian Ice Sheet was the third-largest ice mass during the last Ice Age and retreated from Norway about 20,000 years ago.

Mirroring these retreats are ice sheets on Greenland and Antarctica, which have lost more than 6.4 trillion tons of ice over the past three decades.

“Our research provides a warning from the past about the speeds that ice sheets are physically capable of retreating at,” Christine Batchelor, study co-author and physical geographer from Newcastle University, said in a statement.

They mapped out more than 7,600 small-scale landforms called “Corrugation ridges” on the seafloor around where the ice sheet once stood.

These types of ridges are believed to have formed when the ice sheet’s retreating margin moved with the tide.

Understanding these seafloor landforms also showcases the mechanics behind rapid ice retreat.

The study found that the former ice sheet retreated most across the flattest point of its bed where, “Less melting is required to thin the overlying ice to the point where it starts to float,” explained co-author and Cambridge glacial geophysicist Frazer Christie from Scott in a statement.

“An ice margin can unground from the seafloor and retreat near-instantly when it becomes buoyant.”

Nicknamed the “Doomsday Glacier,” Thwaites could undergo a similar pulse of rapid ice retreat since it has recently retreated close to a flat area of its bed.

“Our findings suggest that present-day rates of melting are sufficient to cause short pulses of rapid retreat across flat-bedded areas of the Antarctic Ice Sheet, including at Thwaites,” said Batchelor.