British Antarctic Survey scientists use tagged seals on expedition to investigate Thwaites Glacier
Scientists will use seals to investigate a glacier the size of Great Britain that is at risk of collapse in West Antarctica.
The team of more than 20 polar scientists, including researchers from the British Antarctic Survey in Cambridge, set sail on Tuesday (January 29) on the first ship-based research expedition to Thwaites Glacier as part of the International Thwaites Glacier Collaboration.
Part of a five-year project to understand whether the glacier is likely to collapse and cause a significant rise in global sea levels, the researchers will spend more than 50 days gathering data on board the US icebreaker Nathaniel B. Palmer.
Astonishingly, if Thwaites Glacier were to melt completely, global sea levels would rise by 80cm.
Ecologist Dr Lars Boehme, from University of St Andrews, will oversee work to tag seals.
He said: “Weddell and elephant seals like hanging out near the ice front or under sea ice, places we find really hard to access.
“The sensors record details about the seal’s immediate physical environment, which gives us a clearer picture of current oceanic conditions in these remote and inaccessible places.”
This data, combined with information from ocean gliders and autonomous vehicles, will uncover how the glacier interacts with the ocean.
A team from University of Gothenburg will perform the first tests in polar waters of a Swedish autonomous underwater vehicle (AUV) - a HUGIN model made by Kongsberg, which can dive to 3,000m. They will collect oceanographic data from the water column and the sea bed.
The researchers will learn not only how the glacier is behaving today, but will gather data enabling them to reconstruct how the Thwaites Glacier responded to environmental change in the past.
Dr Robert Larter, a marine geophysicist from the British Antarctic Survey and chief scientist on board the cruise, said: “Thwaites Glacier holds the key to a much better understanding of future sea-level rise from this vulnerable part of West Antarctica.
“This is our first chance to get a deeper understanding of this ‘wild card’ glacier. Examining the seafloor and sediments at the glacier edge will provide an insight into how the ice has behaved in the past relative to records of environmental conditions. This is important for predicting how the glacier may respond to future climate change.”
The seafloor will be mapped using a technique called swath bathymetry – which uses sonar to measure depth - to establish how the landscape beneath the glacier influenced its past behaviour.
Sediment cores from the seabed will reveal the extent to which the previous retreat of the glacier retreat has been driven by interactions with the ocean.
Dr Rebecca Totten Minzoni, sedimentologist and paleontologist at University of Alabama, said: “It’s exciting to be part of this ship-based expedition to Thwaites Glacier. This is truly a frontier of science, and the knowledge we will gain has real societal impact.
“By discovering the history of Thwaites Glacier under past climate and ocean conditions, we can assess the stability of the glacier today.
“With the majority of the global population living at the coast, including important cultural and industrial centers like my hometown of New Orleans, we need to know how much this vulnerable region of Antarctica will contribute to sea level rise over the coming decades.”
Also on board will be a team collecting samples of rock, penguin bones and shells from nearby islands to carbon date them, which will reveal how sea level has changed in the past 5,000 years and its impact on the ice sheet.
The expedition, part of the International Thwaites Glacier Collaboration funded by the UK Natural Environment Research Council and the US National Science Foundation, willl improve the reliability of the ice sheet models used to predict future sea level change.