KEY POINTS

  • Scientists mapped the glacier's movement and past declines in detail for the first time
  • Findings show the glacier has retreated at a faster rate in the past
  • The recent retreat rate is miniscule in comparison

Antarctica's high-risk Thwaites "doomsday" Glacier is inching toward total collapse, and a new report warns big changes should be expected in the near future as it disintegrates.

Scientists, in a report published Monday, mapped the glacier's movement and past declines in detail for the first time, which in turn has given them an insight into what the future holds for the structure.

The glacier's unstable state was highlighted in never-before-seen high-resolution seafloor images. Scientists made an alarming discovery that the glacier had retreated at a faster rate in the past, and the changes to the structure in recent times were miniscule in comparison.

The images were collected during a 20-hour expedition in 2019. Scientists from the U.S., the United Kingdom and Sweden were part of the historic trip, which allowed them a peek into the glacier front for the very first time.

The team mapped a Houston-sized area of seabed in front of the glacier in extreme weather, with a state-of-the-art robotic submarine called "Rán."

"The images Ran collected gave us vital insights into the processes happening at the critical junction between the glacier and the ocean today," said Anna Wåhlin, a physical oceanographer from the University of Gothenburg, who deployed Rán at Thwaites.

To study the past movements, scientists analyzed the submerged rib-like formations that were created after the glacier's leading edge retreated and moved with the tides.

The findings showed that at some point in the past two centuries, the front of the glacier lost contact with a seabed ridge and retreated at a rate of more than 1.3 miles per year, all within a six-month window. The retreat rate was twice that of what was documented in the past decade.

"Our results suggest that pulses of very rapid retreat have occurred at Thwaites Glacier in the last two centuries, and possibly as recently as the mid-20th Century," team lead Alastair Graham, from the University of South Florida's College of Marine Science, reported Science Daily.

"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," said marine geophysicist and study co-author Robert Larter, of the British Antarctic Survey.

Thwaites's retreat and its threatening effects on life on the planet is a heavily discussed subject among scientists since the beginning of the century. An International Thwaites Glacier Collaboration (ITGC) team, comprising nearly 100 scientists, is dedicatedly studying the vulnerable glacier. The study is funded by the U.S. National Science Foundation.

According to a 2020 finding, Thwaites was eroding from its underwater base due to warming ocean water, and the glacier's grip on the underwater mountain was loosening. Last year, a study highlighted that the ice shelf, which holds the glacier ice from freely floating into the ocean, could shatter in five years as it sustained massive fractures.

"It's doubled its outflow speed within the last 30 years, and the glacier in its entirety holds enough water to raise sea level by over two feet. And it could lead to even more sea-level rise, up to 10 feet, if it draws the surrounding glaciers with it," said Ted Scambos, a senior research scientist at the Cooperative Institute for Research in Environmental Sciences (CIRES) and the U.S lead coordinator for ITGC.

"From the satellite data, we're seeing these big fractures spreading across the ice shelf surface, essentially weakening the fabric of the ice; kind of a bit like a windscreen crack," Peter Davis, an oceanographer with the British Antarctic Survey told CNN last year. "It's slowly spreading across the ice shelf and eventually it's going to fracture into lots of different pieces."

RTR3OUNE
The Thwaites Glacier in Antarctica is seen in this undated image from NASA. Reuters