The field camp on Thwaites glacier where the team were based for drilling. Credit: Greg Balco (Berkeley Geochronology Center).
Scientists from the International Thwaites Glacier Collaboration discovered that the West Antarctic Ice Sheet had been thinner in the past and had actually regrown, recommending that glacial retreat might be reversed. The study used rock samples to show that ice near Thwaites Glacier was at least 35 meters thinner in the last 5000 years and took a minimum of 3000 years to reach its present size. This recovery timeframe positions issues offered the anticipated effect of sea level increase due to imminent climate change.
The West Antarctic Ice Sheet is diminishing, with numerous glaciers throughout the area pulling away and melting at a worrying rate. This was not always the case according to brand-new research study released last month in The Cryosphere. A group of researchers from the International Thwaites Glacier Collaboration (ITGC), consisting of 2 scientists from the British Antarctic Survey (BAS), found that the ice sheet near Thwaites Glacier was thinner in the last few thousand years than it is today. This unforeseen discover programs that glaciers in the area had the ability to grow back following earlier shrinkage.
The contribution from melting Antarctic ice is currently the greatest source of unpredictability in forecasts of how much and how quickly the sea level will rise in the coming centuries and decades. Together with its immediate next-door neighbor, Thwaites Glacier currently dominates the Antarctic contribution to sea level rise.
The rock cores were reclaimed to the laboratory from Thwaites for analysis. Credit: Keir Nichols (Imperial College London).
Jonathan Adams, co-author and PhD trainee at BAS, states:.
” By studying the history of glaciers like Thwaites, we can gain important insight into how the Antarctic Ice Sheet may progress in future. Records of ice sheet modification from rocks that are currently exposed above the ice sheet surface end around 5000 years earlier, so to learn what occurred ever since, we need to study rock presently buried beneath the ice sheet.”.
Utilizing drills specially developed to cut through both ice and the underlying rock, the team recuperated rock samples from deep underneath the ice sheet next to Thwaites Glacier. Their existence can therefore reveal periods in the past when the ice sheet was smaller sized than the present.
Keir Nichols, a glacial geologist from Imperial College London and a lead author of the research study, states:.
” This was a huge team effort: numerous of us spent weeks far from home doing fieldwork in an incredibly remote part of Antarctica, whilst others endured literally thousands of hours in the laboratory examining the rocks we collected. The atoms we determined exist only in small amounts in these rocks, so we were pressing right to the limit of what is presently possible and there was no guarantee it would work. We are excited that this is the first study to reveal the current history of an ice sheet utilizing bedrock collected from directly beneath it.”.
The team found that the rocks they collected were not always covered by ice. Their measurements revealed that, during the past 5000 years, ice near Thwaites Glacier was at least 35 meters thinner than it is now. Their designs showed that its development considering that then– making the ice sheet the size it is today– took at least 3000 years.This discovery reveals that ice sheet retreat in the Thwaites Glacier area can be reversed. The challenge for researchers now is to understand the conditions required to make that possible.
Joanne Johnson, a geologist at BAS and co-author of the research study, says:.
” On the face of it, these results look like excellent news– Thwaites Glacier had the ability to regrow from a smaller configuration in the geologically-recent past. Our research study shows that this healing took more than 3000 years, in a climate that was likely not as warm as what we expect for the coming centuries. If we wish to prevent the effects of water level rise on our world that will arise from continued retreat of the West Antarctic Ice Sheet, that timescale is far longer than we can manage to wait.”.
Referral: “Reversible ice sheet thinning in the Amundsen Sea Embayment during the Late Holocene” by Greg Balco, Nathan Brown, Keir Nichols, Ryan A. Venturelli, Jonathan Adams, Scott Braddock, Seth Campbell, Brent Goehring, Joanne S. Johnson, Dylan H. Rood, Klaus Wilcken, Brenda Hall and John Woodward, 28 April 2023, The Cryosphere.DOI: 10.5194/ tc-17-1787-2023.
Researchers from the International Thwaites Glacier Collaboration discovered that the West Antarctic Ice Sheet had actually been thinner in the past and had regrown, suggesting that glacial retreat could be reversed. The West Antarctic Ice Sheet is shrinking, with numerous glaciers across the region melting and pulling back at a worrying rate. A group of scientists from the International Thwaites Glacier Collaboration (ITGC), consisting of two scientists from the British Antarctic Survey (BAS), found that the ice sheet near Thwaites Glacier was thinner in the last couple of thousand years than it is today. Using drills specifically designed to cut through both ice and the underlying rock, the team recuperated rock samples from deep beneath the ice sheet next to Thwaites Glacier. Their designs showed that its growth considering that then– making the ice sheet the size it is today– took at least 3000 years.This discovery reveals that ice sheet retreat in the Thwaites Glacier region can be reversed.
