60 scientists set off for Thwaites Glacier in the Antarctic
The joint research program between the UK and the USA is entering its second round: almost 100 scientists and support staff set off for Thwaites Glacier in West Antarctica last week. Their findings are intended to predict the glacier’s contribution to global sea level rise.
Thwaites Glacier, which covers an area of 192,000 square kilometers – the size of the UK – is one of the most unstable Antarctic glaciers and is particularly vulnerable to changes in climate and the oceans. In the last 30 years, the amount of ice flowing out of the region has almost doubled, mainly because warm seawater from the Amundsen Sea is circulating under the glacier ice and melting it. Computer models show that the glacier could lose ice even faster over the next few decades if the retreat of the ice continues. Today, the ice flowing from Thwaites Glacier into the Amundsen Sea already accounts for around four percent of global sea level rise. A collapse of the glacier would lead to a significant rise in sea level of around 65 centimetres in the coming centuries.
In 2018, the British Natural Environment Research Council (NERC) and the US National Science Foundation (NSF) founded a partnership, the International Thwaites Glacier Collaboration, or ITGC for short, to research the dynamics of the glacier and better understand its contribution to global sea level rise.
Professor David Vaughan, Scientific Director at the British Antarctic Survey and Chief Scientific Coordinator for the ITGC in the UK says:
“I have worked in Antarctica for over 30 years and for many years we have known that Thwaites Glacier is the key to a much better understanding of sea level rise. This is our first opportunity to better understand this unknown but important glacier.
Because of its remoteness, fewer than 100 people have ever set foot on Thwaites Glacier. So what we are planning is hugely ambitious and challenging. This joint effort between the UK and the US will go a long way to ensuring that we can provide governments with the right information for policy and business action that will help protect coastal towns, ecosystems and vulnerable communities in the future.”
Thwaites Glacier is extremely remote; the study sites on the glacier are more than 1,600 kilometers away from the British Rothera Research Station and the McMurdo Station of the American Antarctic Program. Scientists, support staff and equipment are transported to the sites via several camps that serve as staging camps. The effort involved is immense – caravan-like trailers are pulled over the snow by huge tractors and special snowplanes with skids are used. Most of the researchers will travel via McMurdo Station and then continue east to the camps near the Antarctic coast.
The various ITGC research teams that left last week will be busy with fieldwork until March 2020.
In the second of the four field seasons, which will take place in the austral summer, five of the ITGC’s eight research projects will be actively involved, focusing on various aspects of the glacier and its surroundings:
- GHC – Geological History Constraints on the Magnitude of Grounding Line Retreat in the Thwaites Glacier System:
The GHC team will collect information on past ice sheet behavior and relative sea level change in the Thwaites Glacier System. - TARSAN – Thwaites-Amundsen Regional Survey and Network Integrating Atmosphere-Ice-Ocean Processes:
TARSAN investigates from the ship how atmospheric and oceanic processes influence the behavior of the Thwaites and Dotson ice shelves – adjacent ice shelves that behave differently. This research will help to determine how variations in atmospheric or oceanic conditions can affect the behavior and stability of ice shelves in the region. - MELT – Melting at Thwaites grounding zone and its control on sea level:
MELT is an ice-based project designed to investigate how warm water affects the Thwaites Glacier at the baseline – the point from which the glacier floats on the water and becomes an ice shelf. This will allow the potential contribution of the glacier to sea level rise to be predicted more accurately. - TIME – Thwaites Interdisciplinary margin Evolution – The Role of Shear Margin Dynamics in the Future Evolution of Thwaites Drainage Basin:
TIME also observes the shear margins – rapidly deforming regions of the glacier – from the ice using state-of-the-art geophysical methods. These may have a significant influence on the future stability of the West Antarctic Ice Sheet (WAIS). - THOR – Thwaites Offshore Research:
The THOR project is ship- and ice-based and will study the sediments both in the sea in front of the glacier and under the ice shelf together with the glacial relief on the seafloor to reconstruct past changes in ocean conditions and the response of glaciers to these changes.
The various research teams will be housed in an existing camp called West Antarctic Ice Sheet Divide (WAIS Divide), while the equipment will be transported to the sites. By moving from WAIS Divide to the six smaller research camps, the scientists will be able to use a range of methods to study the region:
The MELT team, consisting of glaciologists and engineers, will use hot water jets to drill through the ice at several locations. Through the melted channels, they will lower a series of instruments, including the ICEFIN robot, to study how the glacier interacts with the sea and the sediments below. MELT and TARSAN will survey the region using ice-penetrating radar and active seismic profiling, which should provide important information about the shape of the ice and the ocean basin. The two teams will also deploy multi-sensor stations called AMIGOS – measuring ocean circulation beneath the floating ice shelf as well as weather patterns to investigate the environmental factors that influence the structural stability of the ice shelf.
A THOR researcher plans to take cores of the sediment under the ice through the holes drilled by the MELT and TARSAN teams.
Two teams from the GHC project will be stationed in the Hudson Mountains and on Mount Murphy, where they will collect rocks and determine changes in the height of the ice surface using radar.
A team from TIME will be stationed at the eastern edge of the shear slightly inland from the coast, where it will use radar and passive seismics to measure the rock layer beneath the glacier at its eastern border.
Another team will collect aerogeophysical data on the ice thickness of Thwaites Glacier from the air.
At the end of January, a research expedition will set off from Chile on the American icebreaker Nathaniel B. Palmer to the Amundsen Sea, which will remain in the area until March 2020. The expedition will support the THOR and TARSAN projects, which collect sediment cores from the sea floor. In addition, excellent divers with good local knowledge will also help with data collection – seals will be equipped with sensors to record current and temperature data in the Amundsen Sea. The scientists will not enter the glacier itself, but will study the glacier’s ice loss and the ocean into which it flows. The data will be used to reconstruct the glacier’s historical changes and improve the reliability of the ice sheet models used to predict future sea level changes.
“This is going to challenge our logistics and science efforts in every way,” said Ted Scambos, senior research scientist at the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder and lead science coordinator for the U.S. “It’s a long way out there, it’s a huge project, the weather is notoriously bad and we’re striving to do some really innovative work. It’s going to take the best effort of both nations and a lot of teamwork.”
ITGC is a five-year, 50 million dollar joint mission between the USA and the UK to learn more about the Thwaites Glacier, its past and its future. Significant contributions to the research also come from Sweden, Germany and South Korea. The ultimate goal of the project is to predict how much Thwaites Glacier will contribute to global sea level rise and how quickly a transition to faster ice retreat could occur. ITGC is funded by the US National Science Foundation (NSF) and the UK Natural Environment Research Council (NERC).
Sources: British Antarctic Survey, International Thwaites Glacier Collaboration
