NSFPLR-NERC: GHOST (Geophysical Habitat of Subglacial Thwaites)
Lead Research Organisation:
British Antarctic Survey
Department Name: Science Programmes
Abstract
Costs of rapid sea level rise globally to infrastructure (houses, roads, and farms, etc.) is likely to be large. A possible source of water for sea level rise is the West Antarctic Ice Sheet, and Thwaites Glacier in particular. Ice sheets and glaciers contain vast quantities of water (in the form of ice) that is continually shed to the ocean, and continually replenished by snowfall (from water that evaporates from the oceans). If the amount of ice that Thwaites Glacier loses to the ocean over the next decades is much greater than the amount it receives as snowfall, then sea level in all the world's oceans would rise, possibly as much as a meter (approximately 3 feet). In order to estimate how likely such a catastrophic scenario would be, we need to better understand the surface over which Thwaites Glacier slides. If we can better characterize that layer ("is to smooth? Is it rough? Is it soft? Is it hard?"), then computer models of Thwaites would be much improved and we can make better projections of the amount of ice that Thwaites Glacier would shed to the ocean.
Planned Impact
Better projections of the most important potential contributor to costs of sea-level rise will be of great societal value in decision-making about mitigation and adaptation. The proposed work will also contribute to education of students, advancement of a diverse group of junior faculty, and extension of a vigorous program of education and outreach. Development of a novel interactive educational tool, the Augmented Reality Sandbox, will advance glaciological education in museums and other venues.
International collaboration: We include a significant partnership with the Alfred Wegener Institute, who have agreed to provide a Vibroseis truck, a PistenBully tractor, and personnel for the length of the project, for no cost to NSF or NERC. We include a partnership with Victoria University in NZ who will aid in field work, data analysis, and interpretation.
Further details in Case for Support, submitted via US NSF FastLane portal
International collaboration: We include a significant partnership with the Alfred Wegener Institute, who have agreed to provide a Vibroseis truck, a PistenBully tractor, and personnel for the length of the project, for no cost to NSF or NERC. We include a partnership with Victoria University in NZ who will aid in field work, data analysis, and interpretation.
Further details in Case for Support, submitted via US NSF FastLane portal
Publications
Alley K
(2024)
Evolution of sub-ice-shelf channels reveals changes in ocean-driven melt in West Antarctica
in Journal of Glaciology
Alley R
(2021)
Bedforms of Thwaites Glacier, West Antarctica: Character and Origin
in Journal of Geophysical Research: Earth Surface
Clyne E
(2020)
Interpretation of topography and bed properties beneath Thwaites Glacier, West Antarctica using seismic reflection methods
in Earth and Planetary Science Letters
Jordan T
(2023)
Geological sketch map and implications for ice flow of Thwaites Glacier, West Antarctica, from integrated aerogeophysical observations
in Science Advances
Lehrmann A
(2025)
Recent benthic foraminifera communities offshore of Thwaites Glacier in the Amundsen Sea, Antarctica: implications for interpretations of fossil assemblages
in Journal of Micropalaeontology
Lepp A
(2022)
Sedimentary Signatures of Persistent Subglacial Meltwater Drainage From Thwaites Glacier, Antarctica
in Frontiers in Earth Science
Muto A
(2019)
Bed-type variability and till (dis)continuity beneath Thwaites Glacier, West Antarctica
in Annals of Glaciology
| Description | A study of the seabed shape off the coast of Antarctica, that was once under the ice sheet, has been used to determine how the shape of the landscape under the ice affects its flow, allowing it to speed up, slow down or change its flow pattern. This will be particularly relevant to predictions of how the movement of the Polar ice sheets might change in the future and the way that might contribute to sea level changes. A study of geophysical surveys shows that the bed of Thwaites Glacier has been sculpted by the flowing ice, eroding large "moats" upglacier and to the sides of bedrock obstacles, and depositing long tails of soft sediment downglacier. Models show that these features formed over time by the interactions among ice, bedrock, and subglacial water and sediment, and that the behaviour of the glacier must have changed as these features developed. This knowledge does not directly affect estimates of the potential for future sea-level rise, but does guide further studies to improve those estimates. |
| Exploitation Route | Improvements to predictions of the future contributions of Polar ice sheets to sea level rise |
| Sectors | Environment |
| Description | International Thwaites Glacier Collaboration - exceptional additional funding |
| Amount | £37,331 (GBP) |
| Organisation | Natural Environment Research Council |
| Sector | Public |
| Country | United Kingdom |
| Start | 08/2023 |
| End | 09/2025 |
| Title | MATLAB script for grain images and grain-shape metrics of glacial sediments from Antarctica, Northwest Greenland, and the central Barents Sea |
| Description | This project explores grain-scale signatures of subglacial sediment transport and subglacial hydrologic processes using grain shape and microtexture. We compare grain-shape distributions for grains from meltwater plume deposits to those of subglacial till and ice-proximal diamicton from the same glacial setting. The study incorporates samples from marine sediment cores collected offshore of Ryder Glacier in northwest Greenland, in the central Barents Sea, and Antarctic samples from Marguerite Bay, offshore Thwaites and Pine Island glaciers, and in the western Ross Sea. This dataset contains a MATLAB script used to process grain images and calculate individual grain-shape metrics (including circularity, solidity, and eccentricity), and an Excel spreadsheet containing the grain-shape measurements. Grain images were collected in 2022-23 using a Bettersizer S3 Plus particle size and shape analyzer at the University of Virginia. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2023 |
| Provided To Others? | Yes |
| URL | https://doi.pangaea.de/10.1594/PANGAEA.961704 |
| Title | Model output from Inverting ice surface elevation and velocity for bed topography and slipperiness beneath Thwaites Glacier |
| Description | This model output dataset accompanies the draft paper 'Inverting ice surface elevation and velocity for bed topography and slipperiness beneath Thwaites Glacier'. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2021 |
| Provided To Others? | Yes |
| URL | https://zenodo.org/record/5105687 |
| Title | Model output from Inverting ice surface elevation and velocity for bed topography and slipperiness beneath Thwaites Glacier |
| Description | This model output dataset accompanies the draft paper 'Inverting ice surface elevation and velocity for bed topography and slipperiness beneath Thwaites Glacier'. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2021 |
| Provided To Others? | Yes |
| URL | https://zenodo.org/record/5105686 |
| Title | Modern benthic foraminifera census and grain-size of surface sediments offshore Thwaites Glacier, Antarctica |
| Description | This dataset includes two procedures: grain-size measurements and modern (rose-bengal stained) benthic foraminifera census offshore Thwaites Glacier. Sediment underwent staining with a rose-bengal ethanol solution for a minimum of 24 hours. Subsequently, the samples were dried, split, and identified for the foraminifera census. Grain-size measurements were conducted on approximately five cubic centimeters of a duplicate Multicore. Thesamples were dispersed using a sodium hexametaphosphate solution for at least 24 hours before being analyzed with a Cilas 1190 laser particle size analyzer. The grain size is reported based on the diameter at which a certain percentage of grains are coarser. For instance, the D90 measurement signifies the diameter at which 90% of grains are coarser. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2024 |
| Provided To Others? | Yes |
| URL | https://doi.pangaea.de/10.1594/PANGAEA.965758 |
| Description | GHOST - AWI oversnow vibroseis |
| Organisation | Alfred-Wegener Institute for Polar and Marine Research |
| Country | Germany |
| Sector | Private |
| PI Contribution | Developed the overall research programme and proposal, of which this collaboration is an integral component. We will provide the conventional oversnow seismic and related geophysical equipment, as well as overall co-ordination of fieldwork with UK (NERC/BAS) and US (NSF/ASC) operations and logistics teams. Overall leadership and co-ordination of the science project. |
| Collaborator Contribution | Complete oversnow vibroseis system. Two personnel for two full Antarctic field seasons. Preparation for fieldwork, and follow-up activities. |
| Impact | Not applicable at this stage. |
| Start Year | 2017 |
| Description | Radar expert Dr Rebecca Schlegel of Tubingen Univeristy joined the Ghost team for field data acquisition and data analysis |
| Organisation | Eberhard Karls University of Tübingen |
| Country | Germany |
| Sector | Academic/University |
| PI Contribution | As an ECR, Dr Schlegel was invited to join ITGC Ghost to develop strong links with leading experts in her field and to give her experience of a leading role in a complex and high profile project. |
| Collaborator Contribution | Dr Schlegel was instrumental in the second Ghost field campaign and is leading one of the key publications form these data to map the bed of Thwaites Glacier. |
| Impact | No outputs at this early stage |
| Start Year | 2023 |
| Title | hockenden97/Inverting_ice_surface: Paper release |
| Description | This code accompanies the draft paper 'Inverting ice surface elevation and velocity for bed topography and slipperiness beneath Thwaites Glacier'. |
| Type Of Technology | Software |
| Year Produced | 2021 |
| URL | https://zenodo.org/record/5494600 |
| Title | hockenden97/Inverting_ice_surface: Paper release |
| Description | This code accompanies the draft paper 'Inverting ice surface elevation and velocity for bed topography and slipperiness beneath Thwaites Glacier'. |
| Type Of Technology | Software |
| Year Produced | 2021 |
| URL | https://zenodo.org/record/5494599 |
| Description | Anglia News TV interview |
| Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Public/other audiences |
| Results and Impact | Anglia News TV interview |
| Year(s) Of Engagement Activity | 2020 |
| Description | BBC TV News interview (World News) |
| Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Public/other audiences |
| Results and Impact | BBC TV News interview (World News). |
| Year(s) Of Engagement Activity | 2020 |
| Description | ITGC press conference for external media |
| Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Media (as a channel to the public) |
| Results and Impact | An in-person and online panel press conference was held at the end of the ITGC Project meeting in Cambridge. Alex Brisbourne was a panel member. Audience members included local and national media, popular science journal and online content creators. The event was organised by ITGC Comms. |
| Year(s) Of Engagement Activity | 2024 |
| URL | https://thwaitesglacier.org/index.php/news/uk-meeting-brings-thwaites-community-together |
| Description | Press conference at EGU 2024 Conference in Vienna |
| Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Media (as a channel to the public) |
| Results and Impact | A press conference was held at the European Geophysical Union conference in Vienna in April 2024. The initial results from our German collaborators at AWI were presented. This led to articles in the German media in particular. |
| Year(s) Of Engagement Activity | 2024 |
| URL | https://thwaitesglacier.org/index.php/news/new-insights-bed-beneath-remote-antarctic-glacier |
| Description | Written and phone responses for news article. |
| Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Public/other audiences |
| Results and Impact | Written and phone responses for news article.Newsweek |
| Year(s) Of Engagement Activity | 2020 |
| Description | Written response for newspaper article |
| Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Public/other audiences |
| Results and Impact | Written responses for newspaper article, the Strait Times, Singapore |
| Year(s) Of Engagement Activity | 2020 |
| Description | Written responses for news article. |
| Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Public/other audiences |
| Results and Impact | Written and phone responses for news article. New Scientist |
| Year(s) Of Engagement Activity | 2020 |