Measuring about 80 miles on the western edge of Antarctica, the Thwaites Glacier is the widest glacier on the planet. But its stability is in jeopardy due to the massive landform losing about 50 billion tons of ice more than it is receiving in snowfall within a year.
Accelerating ice loss has been observed since the 1970s, but it is unclear when this significant melting initiated – until now, according to the UA News Center.
Dr. Rebecca Totten, associate professor in the department of geological sciences, is part of an international, multi-institutional team that discovered the start of the “Doomsday Glacier’s” recent retreat dates to the 1940s.
Part of the International Thwaites Glacier Collaboration, The University of Alabama collaborated in the Thwaites Offshore Research, or THOR, team whose findings were recently published in the journal PNAS. The project is supported by the National Science Foundation and the Natural Environment Research Council.
As a paleoclimatologist, Totten served as co-principal investigator on the project and used her expertise in sediments and microfossils to reconstruct climate and ocean changes.
“I led the coring team at sea and described the samples in this study as they were extracted from the seafloor. I look within these sediments for tiny fossils that provide ages of the sediment layers and tell us about the environments surrounding the glaciers, particularly the water current conditions and the sea surface conditions,” Totten said in a press release. “This new study, led by the University of Houston doctorate student on the cruise, Dr. Rachel Clark, is focused on the retreat of Thwaites Glacier during the last century, which we reconstructed from measuring the age of the sediment from the seafloor and how it changed from deeper, older layers to today.”
Totten was part of the team’s first expedition in 2019 to collect sediment cores offshore Thwaites Glacier, whose “Doomsday” nickname comes from its potential impact on rising sea levels if melting accelerates.
According to researchers, Thwaites Glacier plays a vital role in regulating the stability of the West Antarctic Ice Sheet and, thus, global sea-level rise. If the glacier were to collapse entirely, global sea levels are predicted to rise by 25 inches and have an impact on waters close to home.
The findings of THOR will help future models predict sea-level rise across the globe.
Read more about the Thwaites Glacier and Dr. Rebecca Totten here.