Articles | Volume 14, issue 9
https://doi.org/10.5194/tc-14-2883-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-14-2883-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Sep 2020
Research article |
| 09 Sep 2020
| 09 Sep 2020
Revealing the former bed of Thwaites Glacier using sea-floor bathymetry: implications for warm-water routing and bed controls on ice flow and buttressing
British Antarctic Survey, Natural Environment Research Council,
High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Robert D. Larter
British Antarctic Survey, Natural Environment Research Council,
High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Alastair G. C. Graham
College of
Marine Science, University of South Florida, Saint Petersburg, FL 33701, USA
Robert Arthern
British Antarctic Survey, Natural Environment Research Council,
High Cross, Madingley Road, Cambridge, CB3 0ET, UK
James D. Kirkham
British Antarctic Survey, Natural Environment Research Council,
High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Scott Polar Research Institute, University of Cambridge, Lensfield
Road, Cambridge, CB2 1ER, UK
Rebecca L. Totten
Department of Geological Sciences, University of Alabama, Tuscaloosa,
AL 35487, USA
Tom A. Jordan
British Antarctic Survey, Natural Environment Research Council,
High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Rachel Clark
Department of Earth and Atmospheric Sciences, University of Houston,
Houston, TX 77204, USA
Victoria Fitzgerald
Department of Geological Sciences, University of Alabama, Tuscaloosa,
AL 35487, USA
Anna K. Wåhlin
Department of Marine Sciences, University of Gothenburg, 40530
Göteborg, Sweden
John B. Anderson
Department of Earth Science, Rice University, Houston, TX 77005, USA
Claus-Dieter Hillenbrand
British Antarctic Survey, Natural Environment Research Council,
High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Frank O. Nitsche
Lamont-Doherty Earth Observatory, Columbia University, Palisades, New
York, NY, USA
Lauren Simkins
Department of Environmental Sciences, University of Virginia,
Charlottesville, VA 22904, USA
James A. Smith
British Antarctic Survey, Natural Environment Research Council,
High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Karsten Gohl
Alfred Wegener Institute Helmholtz-Centre for Polar and Marine
Research, 27568 Bremerhaven, Germany
Jan Erik Arndt
Alfred Wegener Institute Helmholtz-Centre for Polar and Marine
Research, 27568 Bremerhaven, Germany
Jongkuk Hong
Korea Polar Research Institute (KOPRI), Incheon 21990, Republic of
Korea
Julia Wellner
Department of Earth and Atmospheric Sciences, University of Houston,
Houston, TX 77204, USA
Related authors
Yavor Kostov, Paul R. Holland, Kelly A. Hogan, James A. Smith, Nicolas C. Jourdain, Pierre Mathiot, Anna Olivé Abelló, Andrew H. Fleming, and Andrew J. S. Meijers
EGUsphere, https://doi.org/10.5194/egusphere-2025-2423, https://doi.org/10.5194/egusphere-2025-2423, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Icebergs ground when they reach shallow topography such as Bear Ridge in the Amundsen Sea. Grounded icebergs can block the transport of sea-ice and create areas of higher and lower sea-ice concentration. We introduce a physically and observationally motivated representation of grounding in an ocean model. In addition, we improve the way simulated icebergs respond to winds, ocean currents, and density differences in sea water. We analyse the forces acting on freely floating and grounded icebergs.
Asmara A. Lehrmann, Rebecca L. Totten, Julia S. Wellner, Claus-Dieter Hillenbrand, Svetlana Radionovskaya, R. Michael Comas, Robert D. Larter, Alastair G. C. Graham, James D. Kirkham, Kelly A. Hogan, Victoria Fitzgerald, Rachel W. Clark, Becky Hopkins, Allison P. Lepp, Elaine Mawbey, Rosemary V. Smyth, Lauren E. Miller, James A. Smith, and Frank O. Nitsche
J. Micropalaeontol., 44, 79–105, https://doi.org/10.5194/jm-44-79-2025, https://doi.org/10.5194/jm-44-79-2025, 2025
Short summary
Short summary
Thwaites Glacier's retreat is driven by warm ocean water melting its ice shelf. Seafloor-dwelling marine protists, benthic foraminifera, reflect their environment. Here, ice margins, oceanography, and sea ice cover control live foraminiferal populations. Including dead foraminifera in the analyses shows the calcareous test preservation's role in the assemblage make-up. Understanding these modern communities helps interpret past glacial retreat controls through foraminifera in sediment records.
Kelly A. Hogan, Katarzyna L. P. Warburton, Alastair G. C. Graham, Jerome A. Neufeld, Duncan R. Hewitt, Julian A. Dowdeswell, and Robert D. Larter
The Cryosphere, 17, 2645–2664, https://doi.org/10.5194/tc-17-2645-2023, https://doi.org/10.5194/tc-17-2645-2023, 2023
Short summary
Short summary
Delicate sea floor ridges – corrugation ridges – that form by tidal motion at Antarctic grounding lines record extremely fast retreat of ice streams in the past. Here we use a mathematical model, constrained by real-world observations from Thwaites Glacier, West Antarctica, to explore how corrugation ridges form. We identify
till extrusion, whereby deformable sediment is squeezed out from under the ice like toothpaste as it settles down at each low-tide position, as the most likely process.
Tom A. Jordan, David Porter, Kirsty Tinto, Romain Millan, Atsuhiro Muto, Kelly Hogan, Robert D. Larter, Alastair G. C. Graham, and John D. Paden
The Cryosphere, 14, 2869–2882, https://doi.org/10.5194/tc-14-2869-2020, https://doi.org/10.5194/tc-14-2869-2020, 2020
Short summary
Short summary
Linking ocean and ice sheet processes allows prediction of sea level change. Ice shelves form a floating buffer between the ice–ocean systems, but the water depth beneath is often a mystery, leaving a critical blind spot in our understanding of how these systems interact. Here, we use airborne measurements of gravity to reveal the bathymetry under the ice shelves flanking the rapidly changing Thwaites Glacier and adjacent glacier systems, providing new insights and data for future models.
Kelly A. Hogan, Martin Jakobsson, Larry Mayer, Brendan T. Reilly, Anne E. Jennings, Joseph S. Stoner, Tove Nielsen, Katrine J. Andresen, Egon Nørmark, Katrien A. Heirman, Elina Kamla, Kevin Jerram, Christian Stranne, and Alan Mix
The Cryosphere, 14, 261–286, https://doi.org/10.5194/tc-14-261-2020, https://doi.org/10.5194/tc-14-261-2020, 2020
Short summary
Short summary
Glacial sediments in fjords hold a key record of environmental and ice dynamic changes during ice retreat. Here we use a comprehensive geophysical survey from the Petermann Fjord system in NW Greenland to map these sediments, identify depositional processes and calculate glacial erosion rates for the retreating palaeo-Petermann ice stream. Ice streaming is the dominant control on glacial erosion rates which vary by an order of magnitude during deglaciation and are in line with modern rates.
James D. Kirkham, Kelly A. Hogan, Robert D. Larter, Neil S. Arnold, Frank O. Nitsche, Nicholas R. Golledge, and Julian A. Dowdeswell
The Cryosphere, 13, 1959–1981, https://doi.org/10.5194/tc-13-1959-2019, https://doi.org/10.5194/tc-13-1959-2019, 2019
Short summary
Short summary
A series of huge (500 m wide, 50 m deep) channels were eroded by water flowing beneath Pine Island and Thwaites glaciers in the past. The channels are similar to canyon systems produced by floods of meltwater released beneath the Antarctic Ice Sheet millions of years ago. The spatial extent of the channels formed beneath Pine Island and Thwaites glaciers demonstrates significant quantities of water, possibly discharged from trapped subglacial lakes, flowed beneath these glaciers in the past.
Robert D. Larter, Kelly A. Hogan, Claus-Dieter Hillenbrand, James A. Smith, Christine L. Batchelor, Matthieu Cartigny, Alex J. Tate, James D. Kirkham, Zoë A. Roseby, Gerhard Kuhn, Alastair G. C. Graham, and Julian A. Dowdeswell
The Cryosphere, 13, 1583–1596, https://doi.org/10.5194/tc-13-1583-2019, https://doi.org/10.5194/tc-13-1583-2019, 2019
Short summary
Short summary
We present high-resolution bathymetry data that provide the most complete and detailed imagery of any Antarctic palaeo-ice stream bed. These data show how subglacial water was delivered to and influenced the dynamic behaviour of the ice stream. Our observations provide insights relevant to understanding the behaviour of modern ice streams and forecasting the contributions that they will make to future sea level rise.
Dominic A. Hodgson, Tom A. Jordan, Jan De Rydt, Peter T. Fretwell, Samuel A. Seddon, David Becker, Kelly A. Hogan, Andrew M. Smith, and David G. Vaughan
The Cryosphere, 13, 545–556, https://doi.org/10.5194/tc-13-545-2019, https://doi.org/10.5194/tc-13-545-2019, 2019
Short summary
Short summary
The Brunt Ice Shelf in Antarctica is home to Halley VIa, the latest in a series of six British research stations that have occupied the ice shelf since 1956. A recent rapid growth of rifts in the Brunt Ice Shelf signals the onset of its largest calving event since records began. Here we consider whether this calving event will lead to a new steady state for the ice shelf or an unpinning from the bed, which could predispose it to accelerated flow or collapse.
Dominic A. Hodgson, Kelly Hogan, James M. Smith, James A. Smith, Claus-Dieter Hillenbrand, Alastair G. C. Graham, Peter Fretwell, Claire Allen, Vicky Peck, Jan-Erik Arndt, Boris Dorschel, Christian Hübscher, Andrew M. Smith, and Robert Larter
The Cryosphere, 12, 2383–2399, https://doi.org/10.5194/tc-12-2383-2018, https://doi.org/10.5194/tc-12-2383-2018, 2018
Short summary
Short summary
We studied the Coats Land ice margin, Antarctica, providing a multi-disciplinary geophysical assessment of the ice sheet configuration through its last advance and retreat; a description of the physical constraints on the stability of the past and present ice and future margin based on its submarine geomorphology and ice-sheet geometry; and evidence that once detached from the bed, the ice shelves in this region were predisposed to rapid retreat back to coastal grounding lines.
Yavor Kostov, Paul R. Holland, Kelly A. Hogan, James A. Smith, Nicolas C. Jourdain, Pierre Mathiot, Anna Olivé Abelló, Andrew H. Fleming, and Andrew J. S. Meijers
EGUsphere, https://doi.org/10.5194/egusphere-2025-2423, https://doi.org/10.5194/egusphere-2025-2423, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Icebergs ground when they reach shallow topography such as Bear Ridge in the Amundsen Sea. Grounded icebergs can block the transport of sea-ice and create areas of higher and lower sea-ice concentration. We introduce a physically and observationally motivated representation of grounding in an ocean model. In addition, we improve the way simulated icebergs respond to winds, ocean currents, and density differences in sea water. We analyse the forces acting on freely floating and grounded icebergs.
Alexander T. Bradley, David T. Bett, C. Rosie Williams, Robert J. Arthern, Paul R. Holland, James Bryne, and Tamsin L. Edwards
EGUsphere, https://doi.org/10.5194/egusphere-2025-2315, https://doi.org/10.5194/egusphere-2025-2315, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
At least since we started measuring in detail, the West Antarctic Ice Sheet has lost a lot of ice, but we don't know if climate change is responsible. In this work, we put a number on the role of climate change in retreat of a glacier in this ice sheet, for the first time. We show that climate change made the shrinking of this glacier much worse. Our work also suggests that what happened on very long timescales (the last 10,000 years) might also matter for retreat of the ice sheets today.
Ewa Demianiuk, Mateusz Baca, Danijela Popović, Inès Barrenechea Angeles, Ngoc-Loi Nguyen, Jan Pawlowski, John B. Anderson, and Wojciech Majewski
Biogeosciences, 22, 2601–2620, https://doi.org/10.5194/bg-22-2601-2025, https://doi.org/10.5194/bg-22-2601-2025, 2025
Short summary
Short summary
Ancient foraminiferal DNA is studied in five Antarctic cores with sediments up to 25 kyr old. We use a standard and a new, more effective marker, which may become the next standard for paleoenvironmental studies. Much less diverse foraminifera occur on slopes of submarine moraines than in open-marine settings. Soft-walled foraminifera, not found in the fossil record, are especially abundant. There is no foraminiferal DNA in tills, suggesting its destruction during glacial redeposition.
Álvaro Arenas-Pingarrón, Alex M. Brisbourne, Carlos Martín, Hugh F. J. Corr, Carl Robinson, Tom A. Jordan, and Paul V. Brennan
EGUsphere, https://doi.org/10.5194/egusphere-2025-1068, https://doi.org/10.5194/egusphere-2025-1068, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Synthetic Aperture Radar (SAR) imaging is essential for deep englacial observations. Each pixel is formed by averaging the radar echoes within an antenna beamwidth, but the echo diversity is lost after the average. We improve the SAR interpretation if three sub-images are formed with different sub-beamwidths: each is coloured in red, green, or blue, and they are overlapped, creating a coloured image. Interpreters will better identify the slopes of internal layers, crevasses, and layer roughness.
Asmara A. Lehrmann, Rebecca L. Totten, Julia S. Wellner, Claus-Dieter Hillenbrand, Svetlana Radionovskaya, R. Michael Comas, Robert D. Larter, Alastair G. C. Graham, James D. Kirkham, Kelly A. Hogan, Victoria Fitzgerald, Rachel W. Clark, Becky Hopkins, Allison P. Lepp, Elaine Mawbey, Rosemary V. Smyth, Lauren E. Miller, James A. Smith, and Frank O. Nitsche
J. Micropalaeontol., 44, 79–105, https://doi.org/10.5194/jm-44-79-2025, https://doi.org/10.5194/jm-44-79-2025, 2025
Short summary
Short summary
Thwaites Glacier's retreat is driven by warm ocean water melting its ice shelf. Seafloor-dwelling marine protists, benthic foraminifera, reflect their environment. Here, ice margins, oceanography, and sea ice cover control live foraminiferal populations. Including dead foraminifera in the analyses shows the calcareous test preservation's role in the assemblage make-up. Understanding these modern communities helps interpret past glacial retreat controls through foraminifera in sediment records.
Kevin Hank, Robert J. Arthern, C. Rosie Williams, Alex M. Brisbourne, Andrew M. Smith, James A. Smith, Anna Wåhlin, and Sridhar Anandakrishnan
EGUsphere, https://doi.org/10.5194/egusphere-2025-764, https://doi.org/10.5194/egusphere-2025-764, 2025
Short summary
Short summary
The slipperiness beneath ice sheets is a key source of uncertainty in sea level rise projections. Using both observations and model output, we infer the most probable representation of basal slipperiness in ice sheet models, enabling more accurate projections. For Pine Island Glacier, our results provide support for a Coulomb-type sliding law and widespread low effective pressures, potentially increasing sliding velocities in prognostic simulations and, hence, sea level rise projections.
James W. Marschalek, Edward Gasson, Tina van de Flierdt, Claus-Dieter Hillenbrand, Martin J. Siegert, and Liam Holder
Geosci. Model Dev., 18, 1673–1708, https://doi.org/10.5194/gmd-18-1673-2025, https://doi.org/10.5194/gmd-18-1673-2025, 2025
Short summary
Short summary
Ice sheet models can help predict how Antarctica's ice sheets respond to environmental change, and such models benefit from comparison to geological data. Here, we use an ice sheet model output and other data to predict the erosion of debris and trace its transport to where it is deposited on the ocean floor. This allows the results of ice sheet modelling to be directly and quantitively compared to real-world data, helping to reduce uncertainty regarding Antarctic sea level contribution.
Shenjie Zhou, Pierre Dutrieux, Claudia F. Giulivi, Adrian Jenkins, Alessandro Silvano, Christopher Auckland, E. Povl Abrahamsen, Michael P. Meredith, Irena Vaňková, Keith W. Nicholls, Peter E. D. Davis, Svein Østerhus, Arnold L. Gordon, Christopher J. Zappa, Tiago S. Dotto, Theodore A. Scambos, Kathyrn L. Gunn, Stephen R. Rintoul, Shigeru Aoki, Craig Stevens, Chengyan Liu, Sukyoung Yun, Tae-Wan Kim, Won Sang Lee, Markus Janout, Tore Hattermann, Julius Lauber, Elin Darelius, Anna Wåhlin, Leo Middleton, Pasquale Castagno, Giorgio Budillon, Karen J. Heywood, Jennifer Graham, Stephen Dye, Daisuke Hirano, and Una Kim Miller
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-54, https://doi.org/10.5194/essd-2025-54, 2025
Preprint under review for ESSD
Short summary
Short summary
We created the first standardised dataset of in-situ ocean measurements time series from around Antarctica collected since 1970s. This includes temperature, salinity, pressure, and currents recorded by instruments deployed in icy, challenging conditions. Our analysis highlights the dominance of tidal currents and separates these from other patterns to study regional energy distribution. This unique dataset offers a foundation for future research on Antarctic ocean dynamics and ice interactions.
Frida S. Hoem, Karlijn van den Broek, Adrián López-Quirós, Suzanna H. A. van de Lagemaat, Steve M. Bohaty, Claus-Dieter Hillenbrand, Robert D. Larter, Tim E. van Peer, Henk Brinkhuis, Francesca Sangiorgi, and Peter K. Bijl
J. Micropalaeontol., 43, 497–517, https://doi.org/10.5194/jm-43-497-2024, https://doi.org/10.5194/jm-43-497-2024, 2024
Short summary
Short summary
The timing and impact of onset of Antarctic Circumpolar Current (ACC) on climate and Antarctic ice are unclear. We reconstruct late Eocene to Miocene southern Atlantic surface ocean environment using microfossil remains of dinoflagellates (dinocysts). Our dinocyst records shows the breakdown of subpolar gyres in the late Oligocene and the transition into a modern-like oceanographic regime with ACC flow, established frontal systems, Antarctic proximal cooling, and sea ice by the late Miocene.
Robert G. Bingham, Julien A. Bodart, Marie G. P. Cavitte, Ailsa Chung, Rebecca J. Sanderson, Johannes C. R. Sutter, Olaf Eisen, Nanna B. Karlsson, Joseph A. MacGregor, Neil Ross, Duncan A. Young, David W. Ashmore, Andreas Born, Winnie Chu, Xiangbin Cui, Reinhard Drews, Steven Franke, Vikram Goel, John W. Goodge, A. Clara J. Henry, Antoine Hermant, Benjamin H. Hills, Nicholas Holschuh, Michelle R. Koutnik, Gwendolyn J.-M. C. Leysinger Vieli, Emma J. Mackie, Elisa Mantelli, Carlos Martín, Felix S. L. Ng, Falk M. Oraschewski, Felipe Napoleoni, Frédéric Parrenin, Sergey V. Popov, Therese Rieckh, Rebecca Schlegel, Dustin M. Schroeder, Martin J. Siegert, Xueyuan Tang, Thomas O. Teisberg, Kate Winter, Shuai Yan, Harry Davis, Christine F. Dow, Tyler J. Fudge, Tom A. Jordan, Bernd Kulessa, Kenichi Matsuoka, Clara J. Nyqvist, Maryam Rahnemoonfar, Matthew R. Siegfried, Shivangini Singh, Verjan Višnjević, Rodrigo Zamora, and Alexandra Zuhr
EGUsphere, https://doi.org/10.5194/egusphere-2024-2593, https://doi.org/10.5194/egusphere-2024-2593, 2024
Short summary
Short summary
The ice sheets covering Antarctica have built up over millenia through successive snowfall events which become buried and preserved as internal surfaces of equal age detectable with ice-penetrating radar. This paper describes an international initiative to work together on this archival data to build a comprehensive 3-D picture of how old the ice is everywhere across Antarctica, and how this will be used to reconstruct past and predict future ice and climate behaviour.
Joseph A. Ruggiero, Reed P. Scherer, Joseph Mastro, Cesar G. Lopez, Marcus Angus, Evie Unger-Harquail, Olivia Quartz, Amy Leventer, and Claus-Dieter Hillenbrand
J. Micropalaeontol., 43, 323–336, https://doi.org/10.5194/jm-43-323-2024, https://doi.org/10.5194/jm-43-323-2024, 2024
Short summary
Short summary
We quantify sea surface temperature (SST) in the past Southern Ocean using the diatom Fragilariopsis kerguelensis that displays variable population with SST. We explore the use of this relatively new proxy by applying it to sediment assemblages from the Sabrina Coast and Amundsen Sea. We find that Amundsen Sea and Sabrina Coast F. kerguelensis populations are different from each other. An understanding of F. kerguelensis dynamics may help us generate an SST proxy to apply to ancient sediments.
Indrani Das, Jowan Barnes, James Smith, Renata Constantino, Sidney Hemming, and Laurie Padman
EGUsphere, https://doi.org/10.5194/egusphere-2024-1564, https://doi.org/10.5194/egusphere-2024-1564, 2024
Short summary
Short summary
George VI Ice Shelf (GVIIS) on the Antarctic Peninsula is currently thinning and the glaciers feeding it are accelerating. Geologic evidence indicates that GVIIS had disintegrated several thousand years ago due to ocean and atmosphere warming. Here, we use remote sensing and numerical modeling to show that strain thinning reduces buttressing of grounded ice, creating a positive feedback of accelerated ice inflow to the southern GVIIS, likely making it more vulnerable than the northern sector.
David T. Bett, Alexander T. Bradley, C. Rosie Williams, Paul R. Holland, Robert J. Arthern, and Daniel N. Goldberg
The Cryosphere, 18, 2653–2675, https://doi.org/10.5194/tc-18-2653-2024, https://doi.org/10.5194/tc-18-2653-2024, 2024
Short summary
Short summary
A new ice–ocean model simulates future ice sheet evolution in the Amundsen Sea sector of Antarctica. Substantial ice retreat is simulated in all scenarios, with some retreat still occurring even with no future ocean melting. The future of small "pinning points" (islands of ice that contact the seabed) is an important control on this retreat. Ocean melting is crucial in causing these features to go afloat, providing the link by which climate change may affect this sector's sea level contribution.
Allison P. Lepp, Lauren E. Miller, John B. Anderson, Matt O'Regan, Monica C. M. Winsborrow, James A. Smith, Claus-Dieter Hillenbrand, Julia S. Wellner, Lindsay O. Prothro, and Evgeny A. Podolskiy
The Cryosphere, 18, 2297–2319, https://doi.org/10.5194/tc-18-2297-2024, https://doi.org/10.5194/tc-18-2297-2024, 2024
Short summary
Short summary
Shape and surface texture of silt-sized grains are measured to connect marine sediment records with subglacial water flow. We find that grain shape alteration is greatest in glaciers where high-energy drainage events and abundant melting of surface ice are inferred and that the surfaces of silt-sized sediments preserve evidence of glacial transport. Our results suggest grain shape and texture may reveal whether glaciers previously experienced temperate conditions with more abundant meltwater.
Charlotte M. Carter, Michael J. Bentley, Stewart S. R. Jamieson, Guy J. G. Paxman, Tom A. Jordan, Julien A. Bodart, Neil Ross, and Felipe Napoleoni
The Cryosphere, 18, 2277–2296, https://doi.org/10.5194/tc-18-2277-2024, https://doi.org/10.5194/tc-18-2277-2024, 2024
Short summary
Short summary
We use radio-echo sounding data to investigate the presence of flat surfaces beneath the Evans–Rutford region in West Antarctica. These surfaces may be what remains of laterally continuous surfaces, formed before the inception of the West Antarctic Ice Sheet, and we assess two hypotheses for their formation. Tectonic structures in the region may have also had a control on the growth of the ice sheet by focusing ice flow into troughs adjoining these surfaces.
Marion A. McKenzie, Lauren E. Miller, Allison P. Lepp, and Regina DeWitt
Clim. Past, 20, 891–908, https://doi.org/10.5194/cp-20-891-2024, https://doi.org/10.5194/cp-20-891-2024, 2024
Short summary
Short summary
Records of the interaction between land and glacial ice movement in the Puget Lowland of Washington State are used to interpret that solid Earth movement provided stability to this marine-terminating glacial ice for at least 500 years. These results are significant because this landscape is similar to parts of the Greenland Ice Sheet and the Antarctic Peninsula, indicating that the interactions seen in this area are applicable to modern glaciated regions.
Rebecca J. Sanderson, Kate Winter, S. Louise Callard, Felipe Napoleoni, Neil Ross, Tom A. Jordan, and Robert G. Bingham
The Cryosphere, 17, 4853–4871, https://doi.org/10.5194/tc-17-4853-2023, https://doi.org/10.5194/tc-17-4853-2023, 2023
Short summary
Short summary
Ice-penetrating radar allows us to explore the internal structure of glaciers and ice sheets to constrain past and present ice-flow conditions. In this paper, we examine englacial layers within the Lambert Glacier in East Antarctica using a quantitative layer tracing tool. Analysis reveals that the ice flow here has been relatively stable, but evidence for former fast flow along a tributary suggests that changes have occurred in the past and could change again in the future.
Benoit S. Lecavalier, Lev Tarasov, Greg Balco, Perry Spector, Claus-Dieter Hillenbrand, Christo Buizert, Catherine Ritz, Marion Leduc-Leballeur, Robert Mulvaney, Pippa L. Whitehouse, Michael J. Bentley, and Jonathan Bamber
Earth Syst. Sci. Data, 15, 3573–3596, https://doi.org/10.5194/essd-15-3573-2023, https://doi.org/10.5194/essd-15-3573-2023, 2023
Short summary
Short summary
The Antarctic Ice Sheet Evolution constraint database version 2 (AntICE2) consists of a large variety of observations that constrain the evolution of the Antarctic Ice Sheet over the last glacial cycle. This includes observations of past ice sheet extent, past ice thickness, past relative sea level, borehole temperature profiles, and present-day bedrock displacement rates. The database is intended to improve our understanding of past Antarctic changes and for ice sheet model calibrations.
Alice C. Frémand, Peter Fretwell, Julien A. Bodart, Hamish D. Pritchard, Alan Aitken, Jonathan L. Bamber, Robin Bell, Cesidio Bianchi, Robert G. Bingham, Donald D. Blankenship, Gino Casassa, Ginny Catania, Knut Christianson, Howard Conway, Hugh F. J. Corr, Xiangbin Cui, Detlef Damaske, Volkmar Damm, Reinhard Drews, Graeme Eagles, Olaf Eisen, Hannes Eisermann, Fausto Ferraccioli, Elena Field, René Forsberg, Steven Franke, Shuji Fujita, Yonggyu Gim, Vikram Goel, Siva Prasad Gogineni, Jamin Greenbaum, Benjamin Hills, Richard C. A. Hindmarsh, Andrew O. Hoffman, Per Holmlund, Nicholas Holschuh, John W. Holt, Annika N. Horlings, Angelika Humbert, Robert W. Jacobel, Daniela Jansen, Adrian Jenkins, Wilfried Jokat, Tom Jordan, Edward King, Jack Kohler, William Krabill, Mette Kusk Gillespie, Kirsty Langley, Joohan Lee, German Leitchenkov, Carlton Leuschen, Bruce Luyendyk, Joseph MacGregor, Emma MacKie, Kenichi Matsuoka, Mathieu Morlighem, Jérémie Mouginot, Frank O. Nitsche, Yoshifumi Nogi, Ole A. Nost, John Paden, Frank Pattyn, Sergey V. Popov, Eric Rignot, David M. Rippin, Andrés Rivera, Jason Roberts, Neil Ross, Anotonia Ruppel, Dustin M. Schroeder, Martin J. Siegert, Andrew M. Smith, Daniel Steinhage, Michael Studinger, Bo Sun, Ignazio Tabacco, Kirsty Tinto, Stefano Urbini, David Vaughan, Brian C. Welch, Douglas S. Wilson, Duncan A. Young, and Achille Zirizzotti
Earth Syst. Sci. Data, 15, 2695–2710, https://doi.org/10.5194/essd-15-2695-2023, https://doi.org/10.5194/essd-15-2695-2023, 2023
Short summary
Short summary
This paper presents the release of over 60 years of ice thickness, bed elevation, and surface elevation data acquired over Antarctica by the international community. These data are a crucial component of the Antarctic Bedmap initiative which aims to produce a new map and datasets of Antarctic ice thickness and bed topography for the international glaciology and geophysical community.
Kelly A. Hogan, Katarzyna L. P. Warburton, Alastair G. C. Graham, Jerome A. Neufeld, Duncan R. Hewitt, Julian A. Dowdeswell, and Robert D. Larter
The Cryosphere, 17, 2645–2664, https://doi.org/10.5194/tc-17-2645-2023, https://doi.org/10.5194/tc-17-2645-2023, 2023
Short summary
Short summary
Delicate sea floor ridges – corrugation ridges – that form by tidal motion at Antarctic grounding lines record extremely fast retreat of ice streams in the past. Here we use a mathematical model, constrained by real-world observations from Thwaites Glacier, West Antarctica, to explore how corrugation ridges form. We identify
till extrusion, whereby deformable sediment is squeezed out from under the ice like toothpaste as it settles down at each low-tide position, as the most likely process.
Marion A. McKenzie, Lauren E. Miller, Jacob S. Slawson, Emma J. MacKie, and Shujie Wang
The Cryosphere, 17, 2477–2486, https://doi.org/10.5194/tc-17-2477-2023, https://doi.org/10.5194/tc-17-2477-2023, 2023
Short summary
Short summary
Topographic highs (“bumps”) across glaciated landscapes have the potential to affect glacial ice. Bumps in the deglaciated Puget Lowland are assessed for streamlined glacial features to provide insight on ice–bed interactions. We identify a general threshold in which bumps significantly disrupt ice flow and sedimentary processes in this location. However, not all bumps have the same degree of impact. The system assessed here has relevance to parts of the Greenland Ice Sheet and Thwaites Glacier.
Michael J. Bentley, James A. Smith, Stewart S. R. Jamieson, Margaret R. Lindeman, Brice R. Rea, Angelika Humbert, Timothy P. Lane, Christopher M. Darvill, Jeremy M. Lloyd, Fiamma Straneo, Veit Helm, and David H. Roberts
The Cryosphere, 17, 1821–1837, https://doi.org/10.5194/tc-17-1821-2023, https://doi.org/10.5194/tc-17-1821-2023, 2023
Short summary
Short summary
The Northeast Greenland Ice Stream is a major outlet of the Greenland Ice Sheet. Some of its outlet glaciers and ice shelves have been breaking up and retreating, with inflows of warm ocean water identified as the likely reason. Here we report direct measurements of warm ocean water in an unusual lake that is connected to the ocean beneath the ice shelf in front of the 79° N Glacier. This glacier has not yet shown much retreat, but the presence of warm water makes future retreat more likely.
James W. Marschalek, Edward Gasson, Tina van de Flierdt, Claus-Dieter Hillenbrand, Martin J. Siegert, and Liam Holder
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2023-8, https://doi.org/10.5194/gmd-2023-8, 2023
Revised manuscript not accepted
Short summary
Short summary
Ice sheet models can help predict how Antarctica’s ice sheets respond to environmental change; such models benefit from comparison to geological data. Here, we use ice sheet model results, plus other data, to predict the erosion of Antarctic debris and trace its transport to where it is deposited on the ocean floor. This allows the results of ice sheet modelling to be directly and quantitively compared to real-world data, helping to reduce uncertainty regarding Antarctic sea level contribution.
James A. Smith, Louise Callard, Michael J. Bentley, Stewart S. R. Jamieson, Maria Luisa Sánchez-Montes, Timothy P. Lane, Jeremy M. Lloyd, Erin L. McClymont, Christopher M. Darvill, Brice R. Rea, Colm O'Cofaigh, Pauline Gulliver, Werner Ehrmann, Richard S. Jones, and David H. Roberts
The Cryosphere, 17, 1247–1270, https://doi.org/10.5194/tc-17-1247-2023, https://doi.org/10.5194/tc-17-1247-2023, 2023
Short summary
Short summary
The Greenland Ice Sheet is melting at an accelerating rate. To understand the significance of these changes we reconstruct the history of one of its fringing ice shelves, known as 79° N ice shelf. We show that the ice shelf disappeared 8500 years ago, following a period of enhanced warming. An important implication of our study is that 79° N ice shelf is susceptible to collapse when atmospheric and ocean temperatures are ~2°C warmer than present, which could occur by the middle of this century.
Paul R. Holland, Gemma K. O'Connor, Thomas J. Bracegirdle, Pierre Dutrieux, Kaitlin A. Naughten, Eric J. Steig, David P. Schneider, Adrian Jenkins, and James A. Smith
The Cryosphere, 16, 5085–5105, https://doi.org/10.5194/tc-16-5085-2022, https://doi.org/10.5194/tc-16-5085-2022, 2022
Short summary
Short summary
The Antarctic Ice Sheet is losing ice, causing sea-level rise. However, it is not known whether human-induced climate change has contributed to this ice loss. In this study, we use evidence from climate models and palaeoclimate measurements (e.g. ice cores) to suggest that the ice loss was triggered by natural climate variations but is now sustained by human-forced climate change. This implies that future greenhouse-gas emissions may influence sea-level rise from Antarctica.
Dominic A. Hodgson, Tom A. Jordan, Neil Ross, Teal R. Riley, and Peter T. Fretwell
The Cryosphere, 16, 4797–4809, https://doi.org/10.5194/tc-16-4797-2022, https://doi.org/10.5194/tc-16-4797-2022, 2022
Short summary
Short summary
This paper describes the drainage (and refill) of a subglacial lake on the Antarctic Peninsula resulting in the collapse of the overlying ice into the newly formed subglacial cavity. It provides evidence of an active hydrological network under the region's glaciers and close coupling between surface climate processes and the base of the ice.
Alice C. Frémand, Julien A. Bodart, Tom A. Jordan, Fausto Ferraccioli, Carl Robinson, Hugh F. J. Corr, Helen J. Peat, Robert G. Bingham, and David G. Vaughan
Earth Syst. Sci. Data, 14, 3379–3410, https://doi.org/10.5194/essd-14-3379-2022, https://doi.org/10.5194/essd-14-3379-2022, 2022
Short summary
Short summary
This paper presents the release of large swaths of airborne geophysical data (including gravity, magnetics, and radar) acquired between 1994 and 2020 over Antarctica by the British Antarctic Survey. These include a total of 64 datasets from 24 different surveys, amounting to >30 % of coverage over the Antarctic Ice Sheet. This paper discusses how these data were acquired and processed and presents the methods used to standardize and publish the data in an interactive and reproducible manner.
Astrid Oetting, Emma C. Smith, Jan Erik Arndt, Boris Dorschel, Reinhard Drews, Todd A. Ehlers, Christoph Gaedicke, Coen Hofstede, Johann P. Klages, Gerhard Kuhn, Astrid Lambrecht, Andreas Läufer, Christoph Mayer, Ralf Tiedemann, Frank Wilhelms, and Olaf Eisen
The Cryosphere, 16, 2051–2066, https://doi.org/10.5194/tc-16-2051-2022, https://doi.org/10.5194/tc-16-2051-2022, 2022
Short summary
Short summary
This study combines a variety of geophysical measurements in front of and beneath the Ekström Ice Shelf in order to identify and interpret geomorphological evidences of past ice sheet flow, extent and retreat.
The maximal extent of grounded ice in this region was 11 km away from the continental shelf break.
The thickness of palaeo-ice on the calving front around the LGM was estimated to be at least 305 to 320 m.
We provide essential boundary conditions for palaeo-ice-sheet models.
Matthew Chadwick, Claire S. Allen, Louise C. Sime, Xavier Crosta, and Claus-Dieter Hillenbrand
Clim. Past, 18, 129–146, https://doi.org/10.5194/cp-18-129-2022, https://doi.org/10.5194/cp-18-129-2022, 2022
Short summary
Short summary
Algae preserved in marine sediments have allowed us to reconstruct how much winter sea ice was present around Antarctica during a past time period (130 000 years ago) when the climate was warmer than today. The patterns of sea-ice increase and decrease vary between different parts of the Southern Ocean. The Pacific sector has a largely stable sea-ice extent, whereas the amount of sea ice in the Atlantic sector is much more variable with bigger decreases and increases than other regions.
Nele Lamping, Juliane Müller, Jens Hefter, Gesine Mollenhauer, Christian Haas, Xiaoxu Shi, Maria-Elena Vorrath, Gerrit Lohmann, and Claus-Dieter Hillenbrand
Clim. Past, 17, 2305–2326, https://doi.org/10.5194/cp-17-2305-2021, https://doi.org/10.5194/cp-17-2305-2021, 2021
Short summary
Short summary
We analysed biomarker concentrations on surface sediment samples from the Antarctic continental margin. Highly branched isoprenoids and GDGTs are used for reconstructing recent sea-ice distribution patterns and ocean temperatures respectively. We compared our biomarker-based results with data obtained from satellite observations and estimated from a numerical model and find reasonable agreements. Further, we address caveats and provide recommendations for future investigations.
Charlotte L. Spencer-Jones, Erin L. McClymont, Nicole J. Bale, Ellen C. Hopmans, Stefan Schouten, Juliane Müller, E. Povl Abrahamsen, Claire Allen, Torsten Bickert, Claus-Dieter Hillenbrand, Elaine Mawbey, Victoria Peck, Aleksandra Svalova, and James A. Smith
Biogeosciences, 18, 3485–3504, https://doi.org/10.5194/bg-18-3485-2021, https://doi.org/10.5194/bg-18-3485-2021, 2021
Short summary
Short summary
Long-term ocean temperature records are needed to fully understand the impact of West Antarctic Ice Sheet collapse. Glycerol dialkyl glycerol tetraethers (GDGTs) are powerful tools for reconstructing ocean temperature but can be difficult to apply to the Southern Ocean. Our results show active GDGT synthesis in relatively warm depths of the ocean. This research improves the application of GDGT palaeoceanographic proxies in the Southern Ocean.
Romana Melis, Lucilla Capotondi, Fiorenza Torricella, Patrizia Ferretti, Andrea Geniram, Jong Kuk Hong, Gerhard Kuhn, Boo-Keun Khim, Sookwan Kim, Elisa Malinverno, Kyu Cheul Yoo, and Ester Colizza
J. Micropalaeontol., 40, 15–35, https://doi.org/10.5194/jm-40-15-2021, https://doi.org/10.5194/jm-40-15-2021, 2021
Short summary
Short summary
Integrated micropaleontological (planktic and benthic foraminifera, diatoms, and silicoflagellates) analysis, together with textural and geochemical results of a deep-sea core from the Hallett Ridge (northwestern Ross Sea), provides new data for late Quaternary (23–2 ka) paleoenvironmental and paleoceanographic reconstructions of this region. Results allow us to identify three time intervals: the glacial–deglacial transition, the deglacial period, and the interglacial period.
Chris S. M. Turney, Richard T. Jones, Nicholas P. McKay, Erik van Sebille, Zoë A. Thomas, Claus-Dieter Hillenbrand, and Christopher J. Fogwill
Earth Syst. Sci. Data, 12, 3341–3356, https://doi.org/10.5194/essd-12-3341-2020, https://doi.org/10.5194/essd-12-3341-2020, 2020
Short summary
Short summary
The Last Interglacial (129–116 ka) experienced global temperatures and sea levels higher than today. The direct contribution of warmer conditions to global sea level (thermosteric) are uncertain. We report a global network of sea surface temperatures. We find mean global annual temperature anomalies of 0.2 ± 0.1˚C and an early maximum peak of 0.9 ± 0.1˚C. Our reconstruction suggests warmer waters contributed on average 0.08 ± 0.1 m and a peak contribution of 0.39 ± 0.1 m to global sea level.
David R. Cox, Paul C. Knutz, D. Calvin Campbell, John R. Hopper, Andrew M. W. Newton, Mads Huuse, and Karsten Gohl
Sci. Dril., 28, 1–27, https://doi.org/10.5194/sd-28-1-2020, https://doi.org/10.5194/sd-28-1-2020, 2020
Short summary
Short summary
A workflow is presented that uses 3D subsurface image (seismic) data to identify and avoid potential geological hazards, in order to increase safety and minimize the risk associated with selecting offshore scientific drilling locations. The workflow has been implemented for a scientific drilling expedition proposal within a challenging region offshore north-western Greenland and resulted in an improved understanding of subsurface hazards and a reduction of risk across all selected drill sites.
Tom A. Jordan, David Porter, Kirsty Tinto, Romain Millan, Atsuhiro Muto, Kelly Hogan, Robert D. Larter, Alastair G. C. Graham, and John D. Paden
The Cryosphere, 14, 2869–2882, https://doi.org/10.5194/tc-14-2869-2020, https://doi.org/10.5194/tc-14-2869-2020, 2020
Short summary
Short summary
Linking ocean and ice sheet processes allows prediction of sea level change. Ice shelves form a floating buffer between the ice–ocean systems, but the water depth beneath is often a mystery, leaving a critical blind spot in our understanding of how these systems interact. Here, we use airborne measurements of gravity to reveal the bathymetry under the ice shelves flanking the rapidly changing Thwaites Glacier and adjacent glacier systems, providing new insights and data for future models.
Stephen L. Cornford, Helene Seroussi, Xylar S. Asay-Davis, G. Hilmar Gudmundsson, Rob Arthern, Chris Borstad, Julia Christmann, Thiago Dias dos Santos, Johannes Feldmann, Daniel Goldberg, Matthew J. Hoffman, Angelika Humbert, Thomas Kleiner, Gunter Leguy, William H. Lipscomb, Nacho Merino, Gaël Durand, Mathieu Morlighem, David Pollard, Martin Rückamp, C. Rosie Williams, and Hongju Yu
The Cryosphere, 14, 2283–2301, https://doi.org/10.5194/tc-14-2283-2020, https://doi.org/10.5194/tc-14-2283-2020, 2020
Short summary
Short summary
We present the results of the third Marine Ice Sheet Intercomparison Project (MISMIP+). MISMIP+ is one in a series of exercises that test numerical models of ice sheet flow in simple situations. This particular exercise concentrates on the response of ice sheet models to the thinning of their floating ice shelves, which is of interest because numerical models are currently used to model the response to contemporary and near-future thinning in Antarctic ice shelves.
Jan Erik Arndt, Robert D. Larter, Claus-Dieter Hillenbrand, Simon H. Sørli, Matthias Forwick, James A. Smith, and Lukas Wacker
The Cryosphere, 14, 2115–2135, https://doi.org/10.5194/tc-14-2115-2020, https://doi.org/10.5194/tc-14-2115-2020, 2020
Short summary
Short summary
We interpret landforms on the seabed and investigate sediment cores to improve our understanding of the past ice sheet development in this poorly understood part of Antarctica. Recent crack development of the Brunt ice shelf has raised concerns about its stability and the security of the British research station Halley. We describe ramp-shaped bedforms that likely represent ice shelf grounding and stabilization locations of the past that may reflect an analogue to the process going on now.
Wei Wei, Donald D. Blankenship, Jamin S. Greenbaum, Noel Gourmelen, Christine F. Dow, Thomas G. Richter, Chad A. Greene, Duncan A. Young, SangHoon Lee, Tae-Wan Kim, Won Sang Lee, and Karen M. Assmann
The Cryosphere, 14, 1399–1408, https://doi.org/10.5194/tc-14-1399-2020, https://doi.org/10.5194/tc-14-1399-2020, 2020
Short summary
Short summary
Getz Ice Shelf is the largest meltwater source from Antarctica of the Southern Ocean. This study compares the relative importance of the meltwater production of Getz from both ocean and subglacial sources. We show that basal melt rates are elevated where bathymetric troughs provide pathways for warm Circumpolar Deep Water to enter the Getz Ice Shelf cavity. In particular, we find that subshelf melting is enhanced where subglacially discharged fresh water flows across the grounding line.
Kelly A. Hogan, Martin Jakobsson, Larry Mayer, Brendan T. Reilly, Anne E. Jennings, Joseph S. Stoner, Tove Nielsen, Katrine J. Andresen, Egon Nørmark, Katrien A. Heirman, Elina Kamla, Kevin Jerram, Christian Stranne, and Alan Mix
The Cryosphere, 14, 261–286, https://doi.org/10.5194/tc-14-261-2020, https://doi.org/10.5194/tc-14-261-2020, 2020
Short summary
Short summary
Glacial sediments in fjords hold a key record of environmental and ice dynamic changes during ice retreat. Here we use a comprehensive geophysical survey from the Petermann Fjord system in NW Greenland to map these sediments, identify depositional processes and calculate glacial erosion rates for the retreating palaeo-Petermann ice stream. Ice streaming is the dominant control on glacial erosion rates which vary by an order of magnitude during deglaciation and are in line with modern rates.
James D. Kirkham, Kelly A. Hogan, Robert D. Larter, Neil S. Arnold, Frank O. Nitsche, Nicholas R. Golledge, and Julian A. Dowdeswell
The Cryosphere, 13, 1959–1981, https://doi.org/10.5194/tc-13-1959-2019, https://doi.org/10.5194/tc-13-1959-2019, 2019
Short summary
Short summary
A series of huge (500 m wide, 50 m deep) channels were eroded by water flowing beneath Pine Island and Thwaites glaciers in the past. The channels are similar to canyon systems produced by floods of meltwater released beneath the Antarctic Ice Sheet millions of years ago. The spatial extent of the channels formed beneath Pine Island and Thwaites glaciers demonstrates significant quantities of water, possibly discharged from trapped subglacial lakes, flowed beneath these glaciers in the past.
Robert D. Larter, Kelly A. Hogan, Claus-Dieter Hillenbrand, James A. Smith, Christine L. Batchelor, Matthieu Cartigny, Alex J. Tate, James D. Kirkham, Zoë A. Roseby, Gerhard Kuhn, Alastair G. C. Graham, and Julian A. Dowdeswell
The Cryosphere, 13, 1583–1596, https://doi.org/10.5194/tc-13-1583-2019, https://doi.org/10.5194/tc-13-1583-2019, 2019
Short summary
Short summary
We present high-resolution bathymetry data that provide the most complete and detailed imagery of any Antarctic palaeo-ice stream bed. These data show how subglacial water was delivered to and influenced the dynamic behaviour of the ice stream. Our observations provide insights relevant to understanding the behaviour of modern ice streams and forecasting the contributions that they will make to future sea level rise.
Dominic A. Hodgson, Tom A. Jordan, Jan De Rydt, Peter T. Fretwell, Samuel A. Seddon, David Becker, Kelly A. Hogan, Andrew M. Smith, and David G. Vaughan
The Cryosphere, 13, 545–556, https://doi.org/10.5194/tc-13-545-2019, https://doi.org/10.5194/tc-13-545-2019, 2019
Short summary
Short summary
The Brunt Ice Shelf in Antarctica is home to Halley VIa, the latest in a series of six British research stations that have occupied the ice shelf since 1956. A recent rapid growth of rifts in the Brunt Ice Shelf signals the onset of its largest calving event since records began. Here we consider whether this calving event will lead to a new steady state for the ice shelf or an unpinning from the bed, which could predispose it to accelerated flow or collapse.
Robert McKay, Neville Exon, Dietmar Müller, Karsten Gohl, Michael Gurnis, Amelia Shevenell, Stuart Henrys, Fumio Inagaki, Dhananjai Pandey, Jessica Whiteside, Tina van de Flierdt, Tim Naish, Verena Heuer, Yuki Morono, Millard Coffin, Marguerite Godard, Laura Wallace, Shuichi Kodaira, Peter Bijl, Julien Collot, Gerald Dickens, Brandon Dugan, Ann G. Dunlea, Ron Hackney, Minoru Ikehara, Martin Jutzeler, Lisa McNeill, Sushant Naik, Taryn Noble, Bradley Opdyke, Ingo Pecher, Lowell Stott, Gabriele Uenzelmann-Neben, Yatheesh Vadakkeykath, and Ulrich G. Wortmann
Sci. Dril., 24, 61–70, https://doi.org/10.5194/sd-24-61-2018, https://doi.org/10.5194/sd-24-61-2018, 2018
Lauren M. Simkins, Sarah L. Greenwood, and John B. Anderson
The Cryosphere, 12, 2707–2726, https://doi.org/10.5194/tc-12-2707-2018, https://doi.org/10.5194/tc-12-2707-2018, 2018
Short summary
Short summary
Using thousands of grounding line landforms in the Ross Sea, Antarctica, we observe two distinct landform types associated with contrasting styles of grounding line retreat. We characterise landform morphology, examine factors that control landform morphology and distribution, and explore drivers of grounding line (in)stability. This study highlights the importance of understanding thresholds which may destabilise a system and of controls on grounding line retreat over a range of timescales.
Dominic A. Hodgson, Kelly Hogan, James M. Smith, James A. Smith, Claus-Dieter Hillenbrand, Alastair G. C. Graham, Peter Fretwell, Claire Allen, Vicky Peck, Jan-Erik Arndt, Boris Dorschel, Christian Hübscher, Andrew M. Smith, and Robert Larter
The Cryosphere, 12, 2383–2399, https://doi.org/10.5194/tc-12-2383-2018, https://doi.org/10.5194/tc-12-2383-2018, 2018
Short summary
Short summary
We studied the Coats Land ice margin, Antarctica, providing a multi-disciplinary geophysical assessment of the ice sheet configuration through its last advance and retreat; a description of the physical constraints on the stability of the past and present ice and future margin based on its submarine geomorphology and ice-sheet geometry; and evidence that once detached from the bed, the ice shelves in this region were predisposed to rapid retreat back to coastal grounding lines.
Jan Erik Arndt, Robert D. Larter, Peter Friedl, Karsten Gohl, Kathrin Höppner, and the Science Team of Expedition PS104
The Cryosphere, 12, 2039–2050, https://doi.org/10.5194/tc-12-2039-2018, https://doi.org/10.5194/tc-12-2039-2018, 2018
Short summary
Short summary
The calving line location of the Pine Island Glacier did not show any trend within the last 70 years until calving in 2015 led to unprecedented retreat. In February 2017 we accessed this previously ice-shelf-covered area with RV Polarstern and mapped the sea-floor topography for the first time. Satellite imagery of the last decades show how the newly mapped shoals affected the ice shelf development and highlights that sea-floor topography is an important factor in initiating calving events.
Yuribia P. Munoz and Julia S. Wellner
The Cryosphere, 12, 205–225, https://doi.org/10.5194/tc-12-205-2018, https://doi.org/10.5194/tc-12-205-2018, 2018
Short summary
Short summary
We mapped submarine landforms in western Antarctic Peninsula bays. These landforms were formed by flowing ice and provide insight into the local controls on glacial ice advance and retreat. We combined data from various cruises to create seafloor maps. We conclude that the number of landforms found in the bays scales to the size of the bay, narrower bays tend to stabilize ice flow, and meltwater channels are abundant, and we hypothesize a recent glacial advance, likely the Little Ice Age.
Janin Schaffer, Ralph Timmermann, Jan Erik Arndt, Steen Savstrup Kristensen, Christoph Mayer, Mathieu Morlighem, and Daniel Steinhage
Earth Syst. Sci. Data, 8, 543–557, https://doi.org/10.5194/essd-8-543-2016, https://doi.org/10.5194/essd-8-543-2016, 2016
Short summary
Short summary
The RTopo-2 data set provides consistent maps of global ocean bathymetry and ice surface topographies for Greenland and Antarctica at 30 arcsec grid spacing. We corrected data from earlier products in the areas of Petermann, Hagen Bræ, and Helheim glaciers, incorporated original data for the floating ice tongue of Nioghalvfjerdsfjorden Glacier, and applied corrections for the geometry of Getz, Abbot, and Fimbul ice shelf cavities. The data set is available from the PANGAEA database.
Anna Ruth W. Halberstadt, Lauren M. Simkins, Sarah L. Greenwood, and John B. Anderson
The Cryosphere, 10, 1003–1020, https://doi.org/10.5194/tc-10-1003-2016, https://doi.org/10.5194/tc-10-1003-2016, 2016
Short summary
Short summary
Geomorphic features on the Ross Sea sea floor provide a record of ice-sheet behaviour during the Last Glacial Maximum and subsequent retreat. Based on extensive mapping of these glacial landforms, a large embayment formed in the eastern Ross Sea. This was followed by complex, late-stage retreat in the western Ross Sea where banks stabilised the ice sheet. Physiography and sea floor geology act as regional controls on ice-sheet dynamics across the Ross Sea.
C. Lavoie, E. W. Domack, E. C. Pettit, T. A. Scambos, R. D. Larter, H.-W. Schenke, K. C. Yoo, J. Gutt, J. Wellner, M. Canals, J. B. Anderson, and D. Amblas
The Cryosphere, 9, 613–629, https://doi.org/10.5194/tc-9-613-2015, https://doi.org/10.5194/tc-9-613-2015, 2015
J. S. Wellner
Sci. Dril., 18, 11–11, https://doi.org/10.5194/sd-18-11-2014, https://doi.org/10.5194/sd-18-11-2014, 2014
K. Hochmuth, K. Gohl, G. Uenzelmann-Neben, and R. Werner
Solid Earth Discuss., https://doi.org/10.5194/sed-6-1863-2014, https://doi.org/10.5194/sed-6-1863-2014, 2014
Revised manuscript not accepted
B. Dorschel, J. Gutt, D. Piepenburg, M. Schröder, and J. E. Arndt
Biogeosciences, 11, 3797–3817, https://doi.org/10.5194/bg-11-3797-2014, https://doi.org/10.5194/bg-11-3797-2014, 2014
H. Fischer, J. Severinghaus, E. Brook, E. Wolff, M. Albert, O. Alemany, R. Arthern, C. Bentley, D. Blankenship, J. Chappellaz, T. Creyts, D. Dahl-Jensen, M. Dinn, M. Frezzotti, S. Fujita, H. Gallee, R. Hindmarsh, D. Hudspeth, G. Jugie, K. Kawamura, V. Lipenkov, H. Miller, R. Mulvaney, F. Parrenin, F. Pattyn, C. Ritz, J. Schwander, D. Steinhage, T. van Ommen, and F. Wilhelms
Clim. Past, 9, 2489–2505, https://doi.org/10.5194/cp-9-2489-2013, https://doi.org/10.5194/cp-9-2489-2013, 2013
F. O. Nitsche, K. Gohl, R. D. Larter, C.-D. Hillenbrand, G. Kuhn, J. A. Smith, S. Jacobs, J. B. Anderson, and M. Jakobsson
The Cryosphere, 7, 249–262, https://doi.org/10.5194/tc-7-249-2013, https://doi.org/10.5194/tc-7-249-2013, 2013
Related subject area
Discipline: Ice sheets | Subject: Antarctic
The impact of regional-scale upper-mantle heterogeneity on glacial isostatic adjustment in West Antarctica
Bathymetry-constrained warm-mode melt estimates derived from analysing oceanic gateways in Antarctica
Satellite data reveal details of glacial isostatic adjustment in the Amundsen Sea Embayment, West Antarctica
Review article: Feature tracing in radio-echo sounding products of terrestrial ice sheets and planetary bodies
Viscoelastic mechanics of tidally induced lake drainage in the grounding zone
A facet-based numerical model to retrieve ice sheet topography from Sentinel-3 altimetry
Current reversal leads to regime change in the Amery Ice Shelf cavity in the 21st century
Speed-up, slowdown, and redirection of ice flow on neighbouring ice streams in the Pope, Smith, and Kohler region of West Antarctica
Changes in Antarctic surface conditions and potential for ice shelf hydrofracturing from 1850 to 2200
A reconstruction of the ice thickness of the Antarctic Peninsula Ice Sheet north of 70° S
Bathymetry-constrained impact of relative sea-level change on basal melting in Antarctica
Age–depth distribution in western Dronning Maud Land, East Antarctica, and Antarctic-wide comparisons of internal reflection horizons
Assessing the sensitivity of the Vanderford Glacier, East Antarctica, to basal melt and calving
A history-matching analysis of the Antarctic Ice Sheet since the Last Interglacial – Part 1: Ice sheet evolution
Gravity-derived Antarctic bathymetry using the Tomofast-x open-source code: a case study of Vincennes Bay
ISMIP6-based Antarctic projections to 2100: simulations with the BISICLES ice sheet model
Assessing the suitability of sites near Pine Island Glacier for subglacial bedrock drilling aimed at detecting Holocene retreat–readvance
Capturing Solid Earth and Ice Sheet Interactions: Insights from Reinforced Ridges in Thwaites Glacier
Modelling GNSS-observed seasonal velocity changes of the Ross Ice Shelf, Antarctica, using the Ice-sheet and Sea-level System Model (ISSM)
The surface mass balance and near-surface climate of the Antarctic ice sheet in RACMO2.4p1
A fast and simplified subglacial hydrological model for the Antarctic Ice Sheet and outlet glaciers
Thwaites Glacier thins and retreats fastest where ice-shelf channels intersect its grounding zone
Melt sensitivity of irreversible retreat of Pine Island Glacier
A model framework for atmosphere–snow water vapor exchange and the associated isotope effects at Dome Argus, Antarctica – Part 1: The diurnal changes
Review Article: Antarctica’s internal architecture: Towards a radiostratigraphically-informed age–depth model of the Antarctic ice sheets
A thicker, rather than thinner, East Antarctic Ice Sheet plateau during the Last Glacial Maximum
The long-term sea-level commitment from Antarctica
The influence of present-day regional surface mass balance uncertainties on the future evolution of the Antarctic Ice Sheet
How well can satellite altimetry and firn models resolve Antarctic firn thickness variations?
Brief Communication: Sensitivity of Antarctic ice-shelf melting to ocean warming across basal melt models
Feedback mechanisms controlling Antarctic glacial-cycle dynamics simulated with a coupled ice sheet–solid Earth model
The effect of ice shelf rheology on shelf edge bending
Hysteresis of idealized, instability-prone outlet glaciers in response to pinning-point buttressing variation
A physics-based Antarctic melt detection technique: combining Advanced Microwave Scanning Radiometer 2, radiative-transfer modeling, and firn modeling
Brief communication: Precision measurement of the index of refraction of deep glacial ice at radio frequencies at Summit Station, Greenland
Widespread increase in discharge from west Antarctic Peninsula glaciers since 2018
Surface dynamics and history of the calving cycle of Astrolabe Glacier (Adélie Coast, Antarctica) derived from satellite imagery
Weak relationship between remotely detected crevasses and inferred ice rheological parameters on Antarctic ice shelves
Extensive palaeo-surfaces beneath the Evans–Rutford region of the West Antarctic Ice Sheet control modern and past ice flow
Towards the systematic reconnaissance of seismic signals from glaciers and ice sheets – Part 1: Event detection for cryoseismology
Towards the systematic reconnaissance of seismic signals from glaciers and ice sheets – Part 2: Unsupervised learning for source process characterization
Geometric amplification and suppression of ice-shelf basal melt in West Antarctica
Alpine topography of the Gamburtsev Subglacial Mountains, Antarctica, mapped from ice sheet surface morphology
Impact of boundary conditions on the modeled thermal regime of the Antarctic ice sheet
Deep learning based automatic grounding line delineation in DInSAR interferograms
The staggered retreat of grounded ice in the Ross Sea, Antarctica, since the Last Glacial Maximum (LGM)
The effect of landfast sea ice buttressing on ice dynamic speedup in the Larsen B embayment, Antarctica
Meteoric water and glacial melt in the southeastern Amundsen Sea: a time series from 1994 to 2020
Evaporative controls on Antarctic precipitation: an ECHAM6 model study using innovative water tracer diagnostics
Disentangling the drivers of future Antarctic ice loss with a historically calibrated ice-sheet model
Erica M. Lucas, Natalya Gomez, and Terry Wilson
The Cryosphere, 19, 2387–2405, https://doi.org/10.5194/tc-19-2387-2025, https://doi.org/10.5194/tc-19-2387-2025, 2025
Short summary
Short summary
We investigate the effects of incorporating regional-scale lateral variability (ca. 50–100 km) in upper-mantle structure into models of Earth deformation and sea level change associated with ice mass changes in West Antarctica. Regional-scale variability in upper-mantle structure is found to impact relative sea level and crustal rate predictions for modern (last ca. 25–125 years) and projected (next ca. 300 years) ice mass changes, especially in coastal regions that undergo rapid ice mass loss.
Lena Nicola, Ronja Reese, Moritz Kreuzer, Torsten Albrecht, and Ricarda Winkelmann
The Cryosphere, 19, 2263–2287, https://doi.org/10.5194/tc-19-2263-2025, https://doi.org/10.5194/tc-19-2263-2025, 2025
Short summary
Short summary
We identify potential oceanic gateways to Antarctic grounding lines based on high-resolution bathymetry data and examine the effect of access depths on ice-shelf melt rates. These gateways manifest the deepest topographic features that could channel warm water masses to the base of the ice sheet. We identify oceanic gateways in several Antarctic regions and estimate an upper bound of melt rate changes in case all warm water masses gain access to the cavities.
Matthias O. Willen, Bert Wouters, Taco Broerse, Eric Buchta, and Veit Helm
The Cryosphere, 19, 2213–2227, https://doi.org/10.5194/tc-19-2213-2025, https://doi.org/10.5194/tc-19-2213-2025, 2025
Short summary
Short summary
Collapse of the West Antarctic Ice Sheet in the Amundsen Sea Embayment is likely in the near future. Vertical uplift of bedrock due to glacial isostatic adjustment stabilizes the ice sheet and may delay its collapse. So far, only spatially and temporally sparse GPS measurements have been able to observe this bedrock motion. We have combined satellite data and quantified a region-wide bedrock motion that independently matches GPS measurements. This can improve ice sheet predictions.
Hameed Moqadam and Olaf Eisen
The Cryosphere, 19, 2159–2196, https://doi.org/10.5194/tc-19-2159-2025, https://doi.org/10.5194/tc-19-2159-2025, 2025
Short summary
Short summary
This is an overview of methodologies that have been applied to map the internal reflection horizons, or ice-layer boundaries, of ice sheets on Earth and other planets. We briefly explain radar applications in glaciology and the methods which have been used and published. There are summaries of the published work of the last 2 decades. Finally, we conclude by introducing the gaps and opportunities for further advancement in this field, and we present possible future directions.
Hanwen Zhang, Richard F. Katz, and Laura A. Stevens
The Cryosphere, 19, 2087–2103, https://doi.org/10.5194/tc-19-2087-2025, https://doi.org/10.5194/tc-19-2087-2025, 2025
Short summary
Short summary
In Antarctica, supraglacial lakes often form near grounding lines due to surface melting. We model viscoelastic tidal flexure in these regions to assess its contribution to lake drainage via hydrofracturing. Results show that tidal flexure and lake-water pressure jointly control drainage near unconfined grounding lines. Sensitivity analysis indicates the importance of the Maxwell time of ice in modulating the tidal response.
Jérémie Aublanc, François Boy, Franck Borde, and Pierre Féménias
The Cryosphere, 19, 1937–1954, https://doi.org/10.5194/tc-19-1937-2025, https://doi.org/10.5194/tc-19-1937-2025, 2025
Short summary
Short summary
In this study we developed a novel processing chain to derive the ice sheet topography from Sentinel-3 altimetry measurements (named "AMPLI"). The major innovation lies in the use of numerical simulations to geolocate the radar impact point on the ground. The performance improvement is substantial compared to ground segment processing. Furthermore, with AMPLI we show that Sentinel-3 estimates the surface elevation change of the Antarctic ice sheet with a high level of agreement with ICESat-2.
Jing Jin, Antony J. Payne, and Christopher Y. S. Bull
The Cryosphere, 19, 1873–1896, https://doi.org/10.5194/tc-19-1873-2025, https://doi.org/10.5194/tc-19-1873-2025, 2025
Short summary
Short summary
The Amery Ice Shelf cavity is one of the largest cold cavities filled by relatively cold Dense Shelf Water. However, in this study, we show that warm intrusion of modified Circumpolar Deep Water flushes the Amery cavity, which changes it from a cold cavity to a warm cavity and leads to an abrupt increase in the basal melt rate in the 2060s. The shift to a warm cavity is attributed to a freshening-driven current reversal in front of the ice shelf.
Heather L. Selley, Anna E. Hogg, Benjamin J. Davison, Pierre Dutrieux, and Thomas Slater
The Cryosphere, 19, 1725–1738, https://doi.org/10.5194/tc-19-1725-2025, https://doi.org/10.5194/tc-19-1725-2025, 2025
Short summary
Short summary
We used satellite observations to measure recent changes in ice speed and flow direction in the Pope, Smith, and Kohler region of West Antarctica (2005–2022). We found substantial speed-up on seven ice streams of up to 87 %. However, Kohler West Glacier has slowed by 10 %, due to the redirection of ice flow into its rapidly thinning neighbour. This process of “ice piracy” has not previously been directly observed on this rapid timescale and may influence future ice shelf and sheet mass changes.
Nicolas C. Jourdain, Charles Amory, Christoph Kittel, and Gaël Durand
The Cryosphere, 19, 1641–1674, https://doi.org/10.5194/tc-19-1641-2025, https://doi.org/10.5194/tc-19-1641-2025, 2025
Short summary
Short summary
A mixed statistical–physical approach is used to reproduce the behaviour of a regional climate model. From that, we estimate the contribution of snowfall and melting at the surface of the Antarctic Ice Sheet to changes in global mean sea level. We also investigate the impact of surface melting in a warmer climate on the stability of the Antarctic ice shelves that provide back stress on the ice flow to the ocean.
Kaian Shahateet, Johannes J. Fürst, Francisco Navarro, Thorsten Seehaus, Daniel Farinotti, and Matthias Braun
The Cryosphere, 19, 1577–1597, https://doi.org/10.5194/tc-19-1577-2025, https://doi.org/10.5194/tc-19-1577-2025, 2025
Short summary
Short summary
In the present work, we provide a new ice thickness reconstruction of the Antarctic Peninsula Ice Sheet north of 70º S using inversion modeling. This model consists of two steps: the first uses basic assumptions of the rheology of the glacier, and the second uses mass conservation to improve the reconstruction where the assumptions made previously are expected to fail. Validation with independent data showed that our reconstruction improved compared to other reconstructions that are available.
Moritz Kreuzer, Torsten Albrecht, Lena Nicola, Ronja Reese, and Ricarda Winkelmann
The Cryosphere, 19, 1181–1203, https://doi.org/10.5194/tc-19-1181-2025, https://doi.org/10.5194/tc-19-1181-2025, 2025
Short summary
Short summary
The study investigates how changing sea levels around Antarctica can potentially affect the melting of floating ice shelves. It utilizes numerical models for both the Antarctic Ice Sheet and the solid Earth, investigating features like troughs and sills that control the flow of ocean water onto the continental shelf. The research finds that compared to climatic changes, the effect of relative sea level on ice-shelf melting is small.
Steven Franke, Daniel Steinhage, Veit Helm, Alexandra M. Zuhr, Julien A. Bodart, Olaf Eisen, and Paul Bons
The Cryosphere, 19, 1153–1180, https://doi.org/10.5194/tc-19-1153-2025, https://doi.org/10.5194/tc-19-1153-2025, 2025
Short summary
Short summary
The study presents internal reflection horizons (IRHs) over an area of 450 000 km² from western Dronning Maud Land, Antarctica, spanning 4.8–91 ka. Using radar and ice core data, nine IRHs were dated and correlated with volcanic events. The data enhance our understanding of the ice sheet's age–depth architecture, accumulation, and dynamics. The findings inform ice flow models and contribute to Antarctic-wide comparisons of IRHs, supporting efforts toward a 3D age–depth ice sheet model.
Lawrence A. Bird, Felicity S. McCormack, Johanna Beckmann, Richard S. Jones, and Andrew N. Mackintosh
The Cryosphere, 19, 955–973, https://doi.org/10.5194/tc-19-955-2025, https://doi.org/10.5194/tc-19-955-2025, 2025
Short summary
Short summary
Vanderford Glacier is the fastest-retreating glacier in East Antarctica and may have important implications for future ice loss from the Aurora Subglacial Basin. Our ice sheet model simulations suggest that grounding line retreat is driven by sub-ice-shelf basal melting, in which warm ocean waters melt ice close to the grounding line. We show that current estimates of basal melt are likely too low, highlighting the need for improved estimates and direct measurements of basal melt in the region.
Benoit S. Lecavalier and Lev Tarasov
The Cryosphere, 19, 919–953, https://doi.org/10.5194/tc-19-919-2025, https://doi.org/10.5194/tc-19-919-2025, 2025
Short summary
Short summary
We present the evolution of the Antarctic Ice Sheet (AIS) over the last 200 kyr by means of a history-matching analysis where an updated observational database constrained ~ 10 000 model simulations. During peak glaciation at the Last Glacial Maximum (LGM), the best-fitting sub-ensemble of AIS simulations reached an excess grounded ice volume relative to the present of 9.2 to 26.5 m equivalent sea level relative to the present. The LGM AIS volume can help resolve the LGM missing-ice problem.
Lawrence A. Bird, Vitaliy Ogarko, Laurent Ailleres, Lachlan Grose, Jeremie Giraud, Felicity S. McCormack, David E. Gwyther, Jason L. Roberts, Richard S. Jones, and Andrew N. Mackintosh
EGUsphere, https://doi.org/10.5194/egusphere-2025-211, https://doi.org/10.5194/egusphere-2025-211, 2025
Short summary
Short summary
The terrain of the seafloor has important controls on the access of warm water to below floating ice shelves around Antarctica. Here, we present an open-source method to infer what the seafloor looks like around the Antarctic continent, and within these ice shelf cavities, using measurements of the Earth’s gravitational field. We present an improved seafloor map for the Vincennes Bay region in East Antarctica and assess its impact on ice melt rates.
James F. O'Neill, Tamsin L. Edwards, Daniel F. Martin, Courtney Shafer, Stephen L. Cornford, Hélène L. Seroussi, Sophie Nowicki, Mira Adhikari, and Lauren J. Gregoire
The Cryosphere, 19, 541–563, https://doi.org/10.5194/tc-19-541-2025, https://doi.org/10.5194/tc-19-541-2025, 2025
Short summary
Short summary
We use an ice sheet model to simulate the Antarctic contribution to sea level over the 21st century under a range of future climates and varying how sensitive the ice sheet is to different processes. We find that ocean temperatures increase and more snow falls on the ice sheet under stronger warming scenarios. When the ice sheet is sensitive to ocean warming, ocean melt-driven loss exceeds snowfall-driven gains, meaning that the sea level contribution is greater with more climate warming.
Joanne S. Johnson, John Woodward, Ian Nesbitt, Kate Winter, Seth Campbell, Keir A. Nichols, Ryan A. Venturelli, Scott Braddock, Brent M. Goehring, Brenda Hall, Dylan H. Rood, and Greg Balco
The Cryosphere, 19, 303–324, https://doi.org/10.5194/tc-19-303-2025, https://doi.org/10.5194/tc-19-303-2025, 2025
Short summary
Short summary
Determining where and when the Antarctic ice sheet was smaller than present requires recovery and exposure dating of subglacial bedrock. Here we use ice sheet model outputs and field data (geological and glaciological observations, bedrock samples, and ground-penetrating radar) to assess the suitability for subglacial drilling of sites in the Hudson Mountains, West Antarctica. We find that no sites are perfect, but two are feasible, with the most suitable being Winkie Nunatak (74.86°S, 99.77°W).
Luc Houriez, Eric Larour, Lambert Caron, Nicole-Jeanne Schlegel, Surendra Adhikari, Erik Ivins, Tyler Pelle, Hélène Seroussi, Eric Darve, and Martin Fischer
EGUsphere, https://doi.org/10.5194/egusphere-2024-4136, https://doi.org/10.5194/egusphere-2024-4136, 2025
Short summary
Short summary
We studied how interactions between the ice sheet and the Earth’s evolving surface affect the future of Thwaites Glacier in Antarctica. We find that small features in the bedrock play a major role in these interactions which can delay the glacier’s retreat by decades or even centuries. This can significantly reduce sea-level rise projections. Our work highlights resolution requirements for similar ice—earth models, and the importance of bedrock mapping efforts in Antarctica.
Francesca Baldacchino, Nicholas R. Golledge, Mathieu Morlighem, Huw Horgan, Alanna V. Alevropoulos-Borrill, Alena Malyarenko, Alexandra Gossart, Daniel P. Lowry, and Laurine van Haastrecht
The Cryosphere, 19, 107–127, https://doi.org/10.5194/tc-19-107-2025, https://doi.org/10.5194/tc-19-107-2025, 2025
Short summary
Short summary
Understanding how the Ross Ice Shelf flow is changing in a warming world is important for predicting ice sheet change. Field measurements show clear intra-annual variations in ice flow; however, it is unclear what mechanisms drive this variability. We show that local perturbations in basal melt can have a significant impact on ice flow speed, but a combination of forcings is likely driving the observed variability in ice flow.
Christiaan T. van Dalum, Willem Jan van de Berg, Michiel R. van den Broeke, and Maurice van Tiggelen
EGUsphere, https://doi.org/10.5194/egusphere-2024-3728, https://doi.org/10.5194/egusphere-2024-3728, 2025
Short summary
Short summary
In this study, we present a new surface mass balance (SMB) and near-surface climate product for Antarctica with the regional climate model RACMO2.4p1. We assess the impact of major model updates on the climate of Antarctica. Locally, the SMB has changed substantially, but also agrees well with observations. In addition, we show that the SMB components, surface energy budget, albedo, pressure, temperature and wind speed compare well with in-situ and remote sensing observations.
Elise Kazmierczak, Thomas Gregov, Violaine Coulon, and Frank Pattyn
The Cryosphere, 18, 5887–5911, https://doi.org/10.5194/tc-18-5887-2024, https://doi.org/10.5194/tc-18-5887-2024, 2024
Short summary
Short summary
We introduce a new fast model for water flow beneath the ice sheet capable of handling various hydrological and bed conditions in a unified way. Applying this model to Thwaites Glacier, we show that accounting for this water flow in ice sheet model projections has the potential to greatly increase the contribution to future sea level rise. We also demonstrate that the sensitivity of the ice sheet in response to external changes depends on the efficiency of the drainage and the bed type.
Allison M. Chartrand, Ian M. Howat, Ian R. Joughin, and Benjamin E. Smith
The Cryosphere, 18, 4971–4992, https://doi.org/10.5194/tc-18-4971-2024, https://doi.org/10.5194/tc-18-4971-2024, 2024
Short summary
Short summary
This study uses high-resolution remote-sensing data to show that shrinking of the West Antarctic Thwaites Glacier’s ice shelf (floating extension) is exacerbated by several sub-ice-shelf meltwater channels that form as the glacier transitions from full contact with the seafloor to fully floating. In mapping these channels, the position of the transition zone, and thinning rates of the Thwaites Glacier, this work elucidates important processes driving its rapid contribution to sea level rise.
Brad Reed, J. A. Mattias Green, Adrian Jenkins, and G. Hilmar Gudmundsson
The Cryosphere, 18, 4567–4587, https://doi.org/10.5194/tc-18-4567-2024, https://doi.org/10.5194/tc-18-4567-2024, 2024
Short summary
Short summary
We use a numerical ice-flow model to simulate the response of a 1940s Pine Island Glacier to changes in melting beneath its ice shelf. A decadal period of warm forcing is sufficient to push the glacier into an unstable, irreversible retreat from its long-term position on a subglacial ridge to an upstream ice plain. This retreat can only be stopped when unrealistic cold forcing is applied. These results show that short warm anomalies can lead to quick and substantial increases in ice flux.
Tianming Ma, Zhuang Jiang, Minghu Ding, Pengzhen He, Yuansheng Li, Wenqian Zhang, and Lei Geng
The Cryosphere, 18, 4547–4565, https://doi.org/10.5194/tc-18-4547-2024, https://doi.org/10.5194/tc-18-4547-2024, 2024
Short summary
Short summary
We constructed a box model to evaluate the isotope effects of atmosphere–snow water vapor exchange at Dome A, Antarctica. The results show clear and invisible diurnal changes in surface snow isotopes under summer and winter conditions, respectively. The model also predicts that the annual net effects of atmosphere–snow water vapor exchange would be overall enrichments in snow isotopes since the effects in summer appear to be greater than those in winter at the study site.
Robert G. Bingham, Julien A. Bodart, Marie G. P. Cavitte, Ailsa Chung, Rebecca J. Sanderson, Johannes C. R. Sutter, Olaf Eisen, Nanna B. Karlsson, Joseph A. MacGregor, Neil Ross, Duncan A. Young, David W. Ashmore, Andreas Born, Winnie Chu, Xiangbin Cui, Reinhard Drews, Steven Franke, Vikram Goel, John W. Goodge, A. Clara J. Henry, Antoine Hermant, Benjamin H. Hills, Nicholas Holschuh, Michelle R. Koutnik, Gwendolyn J.-M. C. Leysinger Vieli, Emma J. Mackie, Elisa Mantelli, Carlos Martín, Felix S. L. Ng, Falk M. Oraschewski, Felipe Napoleoni, Frédéric Parrenin, Sergey V. Popov, Therese Rieckh, Rebecca Schlegel, Dustin M. Schroeder, Martin J. Siegert, Xueyuan Tang, Thomas O. Teisberg, Kate Winter, Shuai Yan, Harry Davis, Christine F. Dow, Tyler J. Fudge, Tom A. Jordan, Bernd Kulessa, Kenichi Matsuoka, Clara J. Nyqvist, Maryam Rahnemoonfar, Matthew R. Siegfried, Shivangini Singh, Verjan Višnjević, Rodrigo Zamora, and Alexandra Zuhr
EGUsphere, https://doi.org/10.5194/egusphere-2024-2593, https://doi.org/10.5194/egusphere-2024-2593, 2024
Short summary
Short summary
The ice sheets covering Antarctica have built up over millenia through successive snowfall events which become buried and preserved as internal surfaces of equal age detectable with ice-penetrating radar. This paper describes an international initiative to work together on this archival data to build a comprehensive 3-D picture of how old the ice is everywhere across Antarctica, and how this will be used to reconstruct past and predict future ice and climate behaviour.
Cari Rand, Richard S. Jones, Andrew N. Mackintosh, Brent Goehring, and Kat Lilly
EGUsphere, https://doi.org/10.5194/egusphere-2024-2674, https://doi.org/10.5194/egusphere-2024-2674, 2024
Short summary
Short summary
In this study, we determine how recently samples from a mountain in East Antarctica were last covered by the East Antarctic ice sheet. By examining concentrations of carbon-14 in rock samples, we determined that all but the summit of the mountain was buried under glacial ice within the last 15 thousand years. Other methods of estimating past ice thicknesses are not sensitive enough to capture ice cover this recent, so we were previously unaware that ice at this site was thicker at this time.
Ann Kristin Klose, Violaine Coulon, Frank Pattyn, and Ricarda Winkelmann
The Cryosphere, 18, 4463–4492, https://doi.org/10.5194/tc-18-4463-2024, https://doi.org/10.5194/tc-18-4463-2024, 2024
Short summary
Short summary
We systematically assess the long-term sea-level response from Antarctica to warming projected over the next centuries, using two ice-sheet models. We show that this committed Antarctic sea-level contribution is substantially higher than the transient sea-level change projected for the coming decades. A low-emission scenario already poses considerable risk of multi-meter sea-level increase over the next millennia, while additional East Antarctic ice loss unfolds under the high-emission pathway.
Christian Wirths, Thomas F. Stocker, and Johannes C. R. Sutter
The Cryosphere, 18, 4435–4462, https://doi.org/10.5194/tc-18-4435-2024, https://doi.org/10.5194/tc-18-4435-2024, 2024
Short summary
Short summary
We investigated the influence of several regional climate models on the Antarctic Ice Sheet when applied as forcing for the Parallel Ice Sheet Model (PISM). Our study shows that the choice of regional climate model forcing results in uncertainties of around a tenth of those in future sea level rise projections and also affects the extent of grounding line retreat in West Antarctica.
Maria T. Kappelsberger, Martin Horwath, Eric Buchta, Matthias O. Willen, Ludwig Schröder, Sanne B. M. Veldhuijsen, Peter Kuipers Munneke, and Michiel R. van den Broeke
The Cryosphere, 18, 4355–4378, https://doi.org/10.5194/tc-18-4355-2024, https://doi.org/10.5194/tc-18-4355-2024, 2024
Short summary
Short summary
The interannual variations in the height of the Antarctic Ice Sheet (AIS) are mainly due to natural variations in snowfall. Precise knowledge of these variations is important for the detection of any long-term climatic trends in AIS surface elevation. We present a new product that spatially resolves these height variations over the period 1992–2017. The product combines the strengths of atmospheric modeling results and satellite altimetry measurements.
Erwin Lambert and Clara Burgard
EGUsphere, https://doi.org/10.5194/egusphere-2024-2358, https://doi.org/10.5194/egusphere-2024-2358, 2024
Short summary
Short summary
The effect of ocean warming on Antarctic ice sheet melting is a major source of uncertainty in estimates of future sea-level rise. We compare five melt models to show that ocean warming strongly increases melting. Despite their calibration on present-day melting, the models disagree on the amount of melt increase. In some important regions, the difference reaches a factor 100. We conclude that using various melt models is important to accurately estimate uncertainties in future sea-level rise.
Torsten Albrecht, Meike Bagge, and Volker Klemann
The Cryosphere, 18, 4233–4255, https://doi.org/10.5194/tc-18-4233-2024, https://doi.org/10.5194/tc-18-4233-2024, 2024
Short summary
Short summary
We performed coupled ice sheet–solid Earth simulations and discovered a positive (forebulge) feedback mechanism for advancing grounding lines, supporting a larger West Antarctic Ice Sheet during the Last Glacial Maximum. During deglaciation we found that the stabilizing glacial isostatic adjustment feedback dominates grounding-line retreat in the Ross Sea, with a weak Earth structure. This may have consequences for present and future ice sheet stability and potential rates of sea-level rise.
W. Roger Buck
The Cryosphere, 18, 4165–4176, https://doi.org/10.5194/tc-18-4165-2024, https://doi.org/10.5194/tc-18-4165-2024, 2024
Short summary
Short summary
Standard theory predicts that the edge of an ice shelf should bend downward. Satellite observations show that the edges of many ice shelves bend upward. A new theory for ice shelf bending is developed that, for the first time, includes the kind of vertical variations in ice flow properties expected for ice shelves. Upward bending of shelf edges is predicted as long as the ice surface is very cold and the ice flow properties depend strongly on temperature.
Johannes Feldmann, Anders Levermann, and Ricarda Winkelmann
The Cryosphere, 18, 4011–4028, https://doi.org/10.5194/tc-18-4011-2024, https://doi.org/10.5194/tc-18-4011-2024, 2024
Short summary
Short summary
Here we show in simplified simulations that the (ir)reversibility of the retreat of instability-prone, Antarctica-type glaciers can strongly depend on the depth of the bed depression they rest on. If it is sufficiently deep, then the destabilized glacier does not recover from its collapsed state. Our results suggest that glaciers resting on a wide and deep bed depression, such as Antarctica's Thwaites Glacier, are particularly susceptible to irreversible retreat.
Marissa E. Dattler, Brooke Medley, and C. Max Stevens
The Cryosphere, 18, 3613–3631, https://doi.org/10.5194/tc-18-3613-2024, https://doi.org/10.5194/tc-18-3613-2024, 2024
Short summary
Short summary
We developed an algorithm based on combining models and satellite observations to identify the presence of surface melt on the Antarctic Ice Sheet. We find that this method works similarly to previous methods by assessing 13 sites and the Larsen C ice shelf. Unlike previous methods, this algorithm is based on physical parameters, and updates to this method could allow the meltwater present on the Antarctic Ice Sheet to be quantified instead of simply detected.
Christoph Welling and The RNO-G Collaboration
The Cryosphere, 18, 3433–3437, https://doi.org/10.5194/tc-18-3433-2024, https://doi.org/10.5194/tc-18-3433-2024, 2024
Short summary
Short summary
We report on the measurement of the index of refraction in glacial ice at radio frequencies. We show that radio echoes from within the ice can be associated with specific features of the ice conductivity and use this to determine the wave velocity. This measurement is especially relevant for the Radio Neutrino Observatory Greenland (RNO-G), a neutrino detection experiment currently under construction at Summit Station, Greenland.
Benjamin J. Davison, Anna E. Hogg, Carlos Moffat, Michael P. Meredith, and Benjamin J. Wallis
The Cryosphere, 18, 3237–3251, https://doi.org/10.5194/tc-18-3237-2024, https://doi.org/10.5194/tc-18-3237-2024, 2024
Short summary
Short summary
Using a new dataset of ice motion, we observed glacier acceleration on the west coast of the Antarctic Peninsula. The speed-up began around January 2021, but some glaciers sped up earlier or later. Using a combination of ship-based ocean temperature observations and climate models, we show that the speed-up coincided with a period of unusually warm air and ocean temperatures in the region.
Floriane Provost, Dimitri Zigone, Emmanuel Le Meur, Jean-Philippe Malet, and Clément Hibert
The Cryosphere, 18, 3067–3079, https://doi.org/10.5194/tc-18-3067-2024, https://doi.org/10.5194/tc-18-3067-2024, 2024
Short summary
Short summary
The recent calving of Astrolabe Glacier in November 2021 presents an opportunity to better understand the processes leading to ice fracturing. Optical-satellite imagery is used to retrieve the calving cycle of the glacier ice tongue and to measure the ice velocity and strain rates in order to document fracture evolution. We observed that the presence of sea ice for consecutive years has favoured the glacier extension but failed to inhibit the growth of fractures that accelerated in June 2021.
Cristina Gerli, Sebastian Rosier, G. Hilmar Gudmundsson, and Sainan Sun
The Cryosphere, 18, 2677–2689, https://doi.org/10.5194/tc-18-2677-2024, https://doi.org/10.5194/tc-18-2677-2024, 2024
Short summary
Short summary
Recent efforts have focused on using AI and satellite imagery to track crevasses for assessing ice shelf damage and informing ice flow models. Our study reveals a weak connection between these observed products and damage maps inferred from ice flow models. While there is some improvement in crevasse-dense regions, this association remains limited. Directly mapping ice damage from satellite observations may not significantly improve the representation of these processes within ice flow models.
Charlotte M. Carter, Michael J. Bentley, Stewart S. R. Jamieson, Guy J. G. Paxman, Tom A. Jordan, Julien A. Bodart, Neil Ross, and Felipe Napoleoni
The Cryosphere, 18, 2277–2296, https://doi.org/10.5194/tc-18-2277-2024, https://doi.org/10.5194/tc-18-2277-2024, 2024
Short summary
Short summary
We use radio-echo sounding data to investigate the presence of flat surfaces beneath the Evans–Rutford region in West Antarctica. These surfaces may be what remains of laterally continuous surfaces, formed before the inception of the West Antarctic Ice Sheet, and we assess two hypotheses for their formation. Tectonic structures in the region may have also had a control on the growth of the ice sheet by focusing ice flow into troughs adjoining these surfaces.
Rebecca B. Latto, Ross J. Turner, Anya M. Reading, and J. Paul Winberry
The Cryosphere, 18, 2061–2079, https://doi.org/10.5194/tc-18-2061-2024, https://doi.org/10.5194/tc-18-2061-2024, 2024
Short summary
Short summary
The study of icequakes allows for investigation of many glacier processes that are unseen by typical reconnaissance methods. However, detection of such seismic signals is challenging due to low signal-to-noise levels and diverse source mechanisms. Here we present a novel algorithm that is optimized to detect signals from a glacier environment. We apply the algorithm to seismic data recorded in the 2010–2011 austral summer from the Whillans Ice Stream and evaluate the resulting event catalogue.
Rebecca B. Latto, Ross J. Turner, Anya M. Reading, Sue Cook, Bernd Kulessa, and J. Paul Winberry
The Cryosphere, 18, 2081–2101, https://doi.org/10.5194/tc-18-2081-2024, https://doi.org/10.5194/tc-18-2081-2024, 2024
Short summary
Short summary
Seismic catalogues are potentially rich sources of information on glacier processes. In a companion study, we constructed an event catalogue for seismic data from the Whillans Ice Stream. Here, we provide a semi-automated workflow for consistent catalogue analysis using an unsupervised cluster analysis. We discuss the defining characteristics of identified signal types found in this catalogue and possible mechanisms for the underlying glacier processes and noise sources.
Jan De Rydt and Kaitlin Naughten
The Cryosphere, 18, 1863–1888, https://doi.org/10.5194/tc-18-1863-2024, https://doi.org/10.5194/tc-18-1863-2024, 2024
Short summary
Short summary
The West Antarctic Ice Sheet is losing ice at an accelerating pace. This is largely due to the presence of warm ocean water around the periphery of the Antarctic continent, which melts the ice. It is generally assumed that the strength of this process is controlled by the temperature of the ocean. However, in this study we show that an equally important role is played by the changing geometry of the ice sheet, which affects the strength of the ocean currents and thereby the melt rates.
Edmund J. Lea, Stewart S. R. Jamieson, and Michael J. Bentley
The Cryosphere, 18, 1733–1751, https://doi.org/10.5194/tc-18-1733-2024, https://doi.org/10.5194/tc-18-1733-2024, 2024
Short summary
Short summary
We use the ice surface expression of the Gamburtsev Subglacial Mountains in East Antarctica to map the horizontal pattern of valleys and ridges in finer detail than possible from previous methods. In upland areas, valleys are spaced much less than 5 km apart, with consequences for the distribution of melting at the bed and hence the likelihood of ancient ice being preserved. Automated mapping techniques were tested alongside manual approaches, with a hybrid approach recommended for future work.
In-Woo Park, Emilia Kyung Jin, Mathieu Morlighem, and Kang-Kun Lee
The Cryosphere, 18, 1139–1155, https://doi.org/10.5194/tc-18-1139-2024, https://doi.org/10.5194/tc-18-1139-2024, 2024
Short summary
Short summary
This study conducted 3D thermodynamic ice sheet model experiments, and modeled temperatures were compared with 15 observed borehole temperature profiles. We found that using incompressibility of ice without sliding agrees well with observed temperature profiles in slow-flow regions, while incorporating sliding in fast-flow regions captures observed temperature profiles. Also, the choice of vertical velocity scheme has a greater impact on the shape of the modeled temperature profile.
Sindhu Ramanath Tarekere, Lukas Krieger, Dana Floricioiu, and Konrad Heidler
EGUsphere, https://doi.org/10.5194/egusphere-2024-223, https://doi.org/10.5194/egusphere-2024-223, 2024
Short summary
Short summary
Grounding lines are geophysical features that divide ice masses on the bedrock and floating ice shelves. Their accurate location is required for calculating the mass balance of ice sheets and glaciers in Antarctica and Greenland. Human experts still manually detect them in satellite-based interferometric radar images, which is inefficient given the growing volume of data. We have developed an artificial intelligence-based automatic detection algorithm to generate Antarctic-wide grounding lines.
Matthew A. Danielson and Philip J. Bart
The Cryosphere, 18, 1125–1138, https://doi.org/10.5194/tc-18-1125-2024, https://doi.org/10.5194/tc-18-1125-2024, 2024
Short summary
Short summary
The post-Last Glacial Maximum (LGM) retreat of the West Antarctic Ice Sheet in the Ross Sea was more significant than for any other Antarctic sector. Here we combined the available dates of retreat with new mapping of sediment deposited by the ice sheet during overall retreat. Our work shows that the post-LGM retreat through the Ross Sea was not uniform. This uneven retreat can cause instability in the present-day Antarctic ice sheet configuration and lead to future runaway retreat.
Trystan Surawy-Stepney, Anna E. Hogg, Stephen L. Cornford, Benjamin J. Wallis, Benjamin J. Davison, Heather L. Selley, Ross A. W. Slater, Elise K. Lie, Livia Jakob, Andrew Ridout, Noel Gourmelen, Bryony I. D. Freer, Sally F. Wilson, and Andrew Shepherd
The Cryosphere, 18, 977–993, https://doi.org/10.5194/tc-18-977-2024, https://doi.org/10.5194/tc-18-977-2024, 2024
Short summary
Short summary
Here, we use satellite observations and an ice flow model to quantify the impact of sea ice buttressing on ice streams on the Antarctic Peninsula. The evacuation of 11-year-old landfast sea ice in the Larsen B embayment on the East Antarctic Peninsula in January 2022 was closely followed by major changes in the calving behaviour and acceleration (30 %) of the ocean-terminating glaciers. Our results show that sea ice buttressing had a negligible direct role in the observed dynamic changes.
Andrew N. Hennig, David A. Mucciarone, Stanley S. Jacobs, Richard A. Mortlock, and Robert B. Dunbar
The Cryosphere, 18, 791–818, https://doi.org/10.5194/tc-18-791-2024, https://doi.org/10.5194/tc-18-791-2024, 2024
Short summary
Short summary
A total of 937 seawater paired oxygen isotope (δ18O)–salinity samples collected during seven cruises on the SE Amundsen Sea between 1994 and 2020 reveal a deep freshwater source with δ18O − 29.4±1.0‰, consistent with the signature of local ice shelf melt. Local mean meteoric water content – comprised primarily of glacial meltwater – increased between 1994 and 2020 but exhibited greater interannual variability than increasing trend.
Qinggang Gao, Louise C. Sime, Alison J. McLaren, Thomas J. Bracegirdle, Emilie Capron, Rachael H. Rhodes, Hans Christian Steen-Larsen, Xiaoxu Shi, and Martin Werner
The Cryosphere, 18, 683–703, https://doi.org/10.5194/tc-18-683-2024, https://doi.org/10.5194/tc-18-683-2024, 2024
Short summary
Short summary
Antarctic precipitation is a crucial component of the climate system. Its spatio-temporal variability impacts sea level changes and the interpretation of water isotope measurements in ice cores. To better understand its climatic drivers, we developed water tracers in an atmospheric model to identify moisture source conditions from which precipitation originates. We find that mid-latitude surface winds exert an important control on moisture availability for Antarctic precipitation.
Violaine Coulon, Ann Kristin Klose, Christoph Kittel, Tamsin Edwards, Fiona Turner, Ricarda Winkelmann, and Frank Pattyn
The Cryosphere, 18, 653–681, https://doi.org/10.5194/tc-18-653-2024, https://doi.org/10.5194/tc-18-653-2024, 2024
Short summary
Short summary
We present new projections of the evolution of the Antarctic ice sheet until the end of the millennium, calibrated with observations. We show that the ocean will be the main trigger of future ice loss. As temperatures continue to rise, the atmosphere's role may shift from mitigating to amplifying Antarctic mass loss already by the end of the century. For high-emission scenarios, this may lead to substantial sea-level rise. Adopting sustainable practices would however reduce the rate of ice loss.
Cited articles
Alley, R. B., Anandakrishnan, S., Dupont, T. K., Parizek, B. R., and
Pollard, D.: Effect of sedimentation on ice-sheet grounding-line stability,
Science, 315, 1838–1841, 2007.
Alley, R. B., Blankenship, D. D., Rooney, S. T., and Bentley, C. R.:
Sedimentation beneath ice shelves – the view from ice stream B, Mar. Geol., 85, 101–120, 1989.
Arndt, J. E., Larter, R. D., Friedl, P., Gohl, K., Höppner, K., and the Science Team of Expedition PS104: Bathymetric controls on calving processes at Pine Island Glacier, The Cryosphere, 12, 2039–2050, https://doi.org/10.5194/tc-12-2039-2018, 2018.
Arndt, J. E., Schenke, H. W., Jakobsson, M., Nitsche, F. O., Buys, G.,
Goleby, B., Rebesco, M., Bohoyo, F., Hong, J., Black, J., Greku, R.,
Udintsev, G., Barrios, F., Reynoso-Peralta, W., Taisei, M., and Wigley, R.:
The International Bathymetric Chart of the Southern Ocean (IBCSO) Version
1.0 – A new bathymetric compilation covering circum-Antarctic waters,
Geophys. Res. Lett., 40, 3111–3117, https://doi.org/10.1002/grl.50413, 2013.
Arthern, R. J., Hindmarsh, R. C. A., and Williams, C. R.: Flow speed within
the Antarctic ice sheet and its controls inferred from satellite
observations, J. Geophys. Res.-Earth, 120,
1171–1188, 2015.
Bellwald, B., Hjelstuen, B. O., Sejrup, H. P., Stokowy, T., and Kuvås,
J.: Holocene mass movements in west and mid-Norwegian fjords and lakes,
Mar. Geol., 407, 192–212, 2019.
Benn, D. I. and Evans, D. J. A.: Glaciers and Glaciation, 2nd Edn., Hodder,
Education, London, 802 pp., ISBN 978-0-340-905791, 2010.
Berger, S., Favier, L., Drews, R., Derwael, J.-J., and Pattyn, F.: The
control of an uncharted pinning point on the flow of an Antarctic ice shelf, J. Glaciol., 62, 37–45, 2016.
Bingham, R. G., Vaughan, D. G., King, E. C., Davies, D., Cornford, S. L.,
Smith, A. M., Arthern, R. J., Brisbourne, A. M., De Rydt, J., Graham, A. G.
C., Spagnolo, M., Marsh, O. J., and Shean, D. E.: Diverse landscapes beneath
Pine Island Glacier influence ice flow, Nat. Commun., 8, 1618,
2017.
Caress, D. W. and Chayes, D. N.: Improved processing of Hydrosweep DS
multibeam data on the R/V Maurice Ewing, Mar. Geophys. Res., 18,
631–650, 1996.
Caress, D. W., Chayes, D. N., and Ferreira, C.: MB-System Seafloor Mapping Software, available at:
https://www.mbari.org/products/research-software/mb-system/, last access:
12 February 2020.
Clark, C. D., Tulaczyk, S. M., Stokes, C. R., and Canals, M.: A
groove-ploughing theory for the production of mega-scale glacial lineations,
and implications for ice-stream mechanics, J. Glaciol., 49,
240–256, 2003.
Davies, D., Bingham, R. G., Graham, A. G. C., Spagnolo, M., Dutrieux, P.,
Vaughan, D. G., Jenkins, A., and Nitsche, F. O.: High-resolution
sub-ice-shelf seafloor records of twentieth century ungrounding and retreat
of Pine Island Glacier, West Antarctica, J. Geophys. Res.-Earth, 122, 1698–1714, 2017.
De Rydt, J. and Gudmundsson, G. H.: Coupled ice shelf-ocean modeling and
complex grounding line retreat from a seabed ridge, J. Geophys. Res.-Earth, 121, 865–880, 2016.
De Rydt, J., Holland, P. R., Dutrieux, P., and Jenkins, A.: Geometric and
oceanographic controls on melting beneath Pine Island Glacier, J. Geophys. Res.-Oceans, 119, 2420–2438, 2014.
Dowdeswell, J. A., Batchelor, C. L., Montelli, A., Ottesen, D., Christie, F.
D. W., Dowdeswell, E. K., and Evans, J.: Delicate seafloor landforms reveal
past Antarctic grounding-line retreat of kilometers per year, Science, 368,
1020, 2020.
Dowdeswell, E. K., Todd, B. J., and Dowdeswell, J. A.: Crag-and-tail
features: convergent ice flow through Eclipse Sound, Baffin Island, Arctic
Canada, edited by: Dowdeswell, J. A., Canals, M., Jakobsson, M., Todd, B. J., Dowdeswell, E. K., and Hogan, K. A., Geological Society, London, Memoirs, 46, 55–56, https://doi.org/10.1144/M46.106, 2016.
Dowdeswell, J. A. and Fugelli, E. M. G.: The seismic architecture and
geometry of grounding-zone wedges formed at the marine margins of past ice
sheets, Geol. Soc. Am. Bull., 124, 1750–1761, 2012.
Dutrieux, P., De Rydt, J., Jenkins, A., Holland, P. R., Ha, H. K., Lee, S. H., Steig, E. J., Ding, Q., Abrahamsen, E. P., and Schröder, M.: Strong Sensitivity of Pine Island Ice-Shelf Melting to Climatic Variability, Science, 343, 174–178, https://doi.org/10.1126/science.1244341, 2014.
Evans, J., Dowdeswell, J. A., Ó Cofaigh, C., Benham, T. J., and
Anderson, J. B.: Extent and dynamics of the West Antarctic Ice Sheet on the
outer continental shelf of Pine Island Bay during the last glaciation,
Mar. Geol., 230, 53–72, 2006.
Falcini, F. M., Rippin, D. M., Krabbendam, M., and Selby, K. A.: Quantifying
bed roughness beneath contemporary and palaeo-ice streams, J. Glaciol., 64, 822–834, 2018.
Favier, L., Durand, G., Cornford, S. L., Gudmundsson, G. H., Gagliardini,
O., Gillet-Chaulet, F., Zwinger, T., Payne, A. J., and Le Brocq, A. M.:
Retreat of Pine Island Glacier controlled by marine ice-sheet instability,
Nat. Clim. Change, 4, 117–121, 2014.
Favier, L., Pattyn, F., Berger, S., and Drews, R.: Dynamic influence of pinning points on marine ice-sheet stability: a numerical study in Dronning Maud Land, East Antarctica, The Cryosphere, 10, 2623–2635, https://doi.org/10.5194/tc-10-2623-2016, 2016.
Ferrigno, J. G., Lucchitta, B. K., Mullins, K. F., Allison, A. L., Allen, R.
J., and Gould, W. G.: Velocity measurements and changes in position of
Thwaites Glacier/iceberg tongue from aerial photography, Landsat images and
NOAA AVHRR data, Ann. Glaciol., 17, 239–244, 1993.
Fowler, A. C. and Nye, J. F.: A sliding law for glaciers of constant
viscosity in the presence of subglacial cavitation, P. R. Soc.-Math. Phys. Sc., 407, 147–170,
1986.
Gales, J. A., Larter, R. D., Mitchell, N. C., and Dowdeswell, J. A.:
Geomorphic signature of Antarctic submarine gullies: Implications for
continental slope processes, Mar. Geol., 337, 112–124, 2013.
Glen, J. W. and Perutz, M. F.: The creep of polycrystalline ice, P. R. Soc.-Math. Phys. Sc., 228, 519–538, 1955.
Gohl, K.: Basement control on past ice sheet dynamics in the Amundsen Sea
Embayment, West Antarctica, Palaeogeogr. Palaeocl., 335–336, 35–41, 2012.
Gohl, K., Denk, A., Eagles, G., and Wobbe, F.: Deciphering tectonic phases
of the Amundsen Sea Embayment shelf, West Antarctica, from a magnetic
anomaly grid, Tectonophysics, 585, 113–123, 2013.
Graham, A. G. C. and Hogan, K. A.: Crescentic scours on palaeo-ice stream
beds, edited by: Dowdeswell, J. A., Canals, M., Jakobsson, M., Todd, B. J., Dowdeswell, E. K., and Hogan, K. A., Memoirs, Geological Society, London, 46, 221–222, https://doi.org/10.1144/M46.166, 2016.
Graham, A. G. C., Larter, R. D., Gohl, K., Hillenbrand, C.-D., Smith, J. A.,
and Kuhn, G.: Bedform signature of a West Antarctic palaeo-ice stream
reveals a multi-temporal record of flow and substrate control, Quaternary Sci. Rev., 28, 2774–2793, 2009.
Graham, A. G. C., Larter, R. D., Gohl, K., Dowdeswell, J. A., Hillenbrand, C.-D., Smith, J. A., Evans, J., Kuhn, G., and
Deen, T.: Flow and retreat of the Late Quaternary Pine Island‐Thwaites palaeo‐ice stream, West Antarctica, J. Geophys.
Res., 115, F03025, https://doi.org/10.1029/2009JF001482, 2010.
Greenwood, S. L., Simkins, L. M., Halberstadt, A. R. W., Prothro, L. O., and
Anderson, J. B.: Holocene reconfiguration and readvance of the East
Antarctic Ice Sheet, Nat. Commun., 9, 3176, 2018.
Ha, H. K., Wåhlin, A. K., Kim, T. W., Lee, S. H., Lee, J. H., Lee, H.
J., Hong, C. S., Arneborg, L., Björk, G., and Kalén, O.: Circulation
and Modification of Warm Deep Water on the Central Amundsen Shelf, J. Phys. Oceanogr., 44, 1493–1501, 2014.
Heywood, K. J., Biddle, L. C., Boehme, L., Dutrieux, P., Fedak, M., Jenkins,
A., Jones, R. W., Kaiser, J., Mallett, H., Garabato, A. C. N., Renfrew, I.
A., Stevens, D. P., and Webber, B. G. M.: Between the Devil and the Deep Blue Sea: The Role of the Amundsen Sea Continental Shelf in Exchanges Between Ocean and Ice Shelves, Oceanography, 29, 118–129, 2016.
Hillenbrand, C.-D., Kuhn, G., Smith, J. A., Gohl, K., Graham, A. G. C.,
Larter, R. D., Klages, J. P., Downey, R., Moreton, S. G., Forwick, M., and
Vaughan, D. G.: Grounding-line retreat of the West Antarctic Ice Sheet from
inner Pine Island Bay, Geology, 41, 35–38, 2013.
Hogan, K. A., Dowdeswell, J. A., and Mienert, J.: New insights into slide
processes and seafloor geology revealed by side-scan imagery of the massive
Hinlopen Slide, Arctic Ocean margin, Geo-Mar. Lett., 33, 325–343, 2013.
Hogan, K. A., Larter, R. D., Graham, A. G. C., Nitsche, F. O., Kirkham, J. D., Totten Minzoni, R., Clark, R., Fitzgerald, V., Anderson, J. B., Hillenbrand, C.-D., Simkins, L., Smith, J. A., Gohl, K., Arndt, J. E., Hong, J., Heywood, K. J., Abrahamsen, E. P., Thompson, A. F., Dunbar, R., and Wellner, J. S.: A multibeam-bathymetric compilation for the southern Amundsen Sea shelf, 1999–2019 (Version 1.0) [Data set], UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation, https://doi.org/10.5285/F2DFEDA9-BF44-4EF5-89A3-EE5E434A385C, 2020.
Holschuh, N., Christianson, K., Paden, J., Alley, R. B., and Anandakrishnan,
S.: Linking postglacial landscapes to glacier dynamics using swath radar
imaging at Thwaites Glacier, Antarctica, Geology, 48, 268–272, 2020.
Holt, J. W., Blankenship, D. D., Morse, D. L., Young, D. A., Peters, M. E.,
Kempf, S. D., Richter, T. G., Vaughan, D. G., and Corr, H. F. J.: New
boundary conditions for the West Antarctic Ice Sheet: Subglacial topography
of the Thwaites and Smith glacier catchments, Geophys. Res. Lett.,
33, L09502, https://doi.org/10.1029/2005GL025561, 2006.
Hubbard, B., Siegert, M. J., and McCarroll, D.: Spectral roughness of
glaciated bedrock geomorphic surfaces: Implications for glacier sliding,
J. Geophys. Res.-Sol. Ea., 105, 21295–21303, 2000.
Hughes, T. J.: The weak underbelly of the West Antarctic ice sheet, J. Glaciol., 27, 518–525, 1981.
Jacobs, S., Giulivi, C., Dutrieux, P., Rignot, E., Nitsche, F., and
Mouginot, J.: Getz Ice Shelf melting response to changes in ocean forcing,
J. Geophys. Res.-Oceans, 118, 4152–4168, 2013.
Jacobs, S., Jenkins, A., Hellmer, H., Giulivi, C., Nitsche, F., Huber, B.,
and Guerrero, R.: The Amundsen Sea and the Antarctic Ice Sheet,
Oceanography, 25, 154–163, 2012.
Jacobs, S. S., Hellmer, H. H., and Jenkins, A.: Antarctic Ice Sheet melting
in the southeast Pacific, Geophys. Res. Lett., 23, 957–960, 1996.
Jakobsson, M., Anderson, J. B., Nitsche, F. O., Gyllencreutz, R., Kirshner,
A. E., Kirchner, N., O'Regan, M., Mohammad, R., and Eriksson, B.: Ice sheet
retreat dynamics inferred from glacial morphology of the central Pine Island
Bay Trough, West Antarctica, Quaternary Sci. Rev., 38, 1–10, 2012.
Jakobsson, M., Nilsson, J., O'Regan, M., Backman, J., Löwemark, L.,
Dowdeswell, J. A., Mayer, L., Polyak, L., Colleoni, F., Anderson, L.,
Björk, G., Darby, D., Eriksson, B., Hanslik, D., Hell, B., Marcussen,
C., Sellén, E., and Wallin, Å.: An Arctic Ocean ice shelf during MIS
6 constrained by new geophysical and geological data, Quaternary Sci. Rev., 29, 3505–3517, 2010.
Jenkins, A., Dutrieux, P., Jacobs, S. S., McPhail, S. D., Perrett, J. R.,
Webb, A. T., and White, D.: Observations beneath Pine Island Glacier in
West Antarctica and implications for its retreat, Nat. Geosci., 3,
468–472, 2010.
Jenkins, A., Dutrieux, P., Jacobs, S., Steig, E. J., Gudmundsson, G. H.,
Smith, J., and Heywood, K. J.: Decadal Ocean Forcing and Antarctic Ice Sheet Response: Lessons from the Amundsen Sea, Oceanography, 29, 106–117, 2016.
Jezek, K., Wu, X., Gogineni, P., Rodríguez, E., Freeman, A.,
Rodriguez-Morales, F., and Clark, C. D.: Radar images of the bed of the
Greenland Ice Sheet, Geophys. Res. Lett., 38, 1–5, https://doi.org/10.1029/2010GL045519, 2011.
Johnson, J. S., Smith, J. A., Schaefer, J.
M., Young, N. E., Goehring, B. M., Hillenbrand, C.-D., Lamp, J. L., Finkel,
R. C., and Gohl, K.: The last glaciation of Bear Peninsula, central Amundsen
Sea Embayment of Antarctica: Constraints on timing and duration revealed by
in situ cosmogenic 14C and 10Be dating, Quaternary Sci. Rev., 178,
77–88, 2017.
Jordan, T. A., Porter, D., Tinto, K., Millan, R., Muto, A., Hogan, K., Larter, R. D.,
Graham, A. G. C., and Pade, J. D.:
New gravity-derived bathymetry for the Thwaites, Crosson, and
Dotson ice shelves revealing two ice shelf populations,
The Cryosphere, 14, 2869–2882, https://doi.org/10.5194/tc-14-2869-2020, 2020.
Jordan, T. M., Cooper, M. A., Schroeder, D. M., Williams, C. N., Paden, J. D., Siegert, M. J., and Bamber, J. L.: Self-affine subglacial roughness: consequences for radar scattering and basal water discrimination in northern Greenland, The Cryosphere, 11, 1247–1264, https://doi.org/10.5194/tc-11-1247-2017, 2017.
Joughin, I., Tulaczyk, S., Bamber, J. L., Blankenship, D., Holt, J. W., Scambos, T., and Vaughan, D. G.: Basal conditions for Pine Island and Thwaites Glaciers, West Antarctica, determined using satellite and airborne data, J. Glaciol., 55, 245–257, 2009.
Joughin, I., Smith, B. E., and Holland, D. M.: Sensitivity of 21st century
sea level to ocean-induced thinning of Pine Island Glacier, Antarctica,
Geophys. Res. Lett., 37, L20502, https://doi.org/10.1029/2010GL044819, 2010.
Joughin, I., Smith, B. E., and Medley, B.: Marine Ice Sheet Collapse
Potentially Under Way for the Thwaites Glacier Basin, West Antarctica,
Science, 344, 735, 2014.
Kamb, B.: Sliding motion of glaciers: theory and observation, Reviews of
Geophysics and Space Physics, 8, 673–728, 1970.
Kim, J.-W., Kim, D.-j., Kim, S. H., Ha, H. K., and Lee, S. H.:
Disintegration and acceleration of Thwaites Ice Shelf on the Amundsen Sea
revealed from remote sensing measurements, Gisci. Remote Sens.,
52, 498–509, 2015.
King, E. C., Pritchard, H. D., and Smith, A. M.: Subglacial landforms
beneath Rutford Ice Stream, Antarctica: detailed bed topography from
ice-penetrating radar, Earth Syst. Sci. Data, 8, 151–158, 2016.
Kirkham, J. D., Hogan, K. A., Larter, R. D., Arnold, N. S., Nitsche, F. O., Golledge, N. R., and Dowdeswell, J. A.: Past water flow beneath Pine Island and Thwaites glaciers, West Antarctica, The Cryosphere, 13, 1959–1981, https://doi.org/10.5194/tc-13-1959-2019, 2019.
Kirshner, A., Anderson, J.B., Jakobsson, M., O'Regan, M., Majewski, W., and
Nitsche, F.: Post-LGM deglaciation in Pine island Bay, west Antarctica.
Quaternary Sci. Rev., 38, 11–26, 2012.
Kuhn, G., Hillenbrand, C.-D., Kasten, S., Smith, J. A., Nitsche, F. O.,
Frederichs, T., Wiers, S., Ehrmann, W., Klages, J. P., and Mogollón, J.
M.: Evidence for a palaeo-subglacial lake on the Antarctic continental
shelf, Nat. Commun., 8, 15591, https://doi.org/10.1038/ncomms15591, 2017.
Larter, R. D., Gohl, K., Hillenbrand, C.-D., Kuhn, G., Deen, T. J., Dietrich, R., Eagles, G., Johnson, J. S., Livermore, R. A., Nitsche, F. O., Pudsey, C. J., Schenke, H.-W., Smith, J. A., Udintsev, G., and Uenzelmann-Neben, G.: West Antarctic Ice Sheet change since the Last Glacial Period, Eos T. Am. Geophys. Un., 88, 189–190, 2007.
Larter, R. D., Graham, A. G. C., Gohl, K., Kuhn, G., Hillenbrand, C.-D.,
Smith, J. A., Deen, T. J., Livermore, R. A., and Schenke, H.-W.: Subglacial
bedforms reveal complex basal regime in a zone of paleo–ice stream
convergence, Amundsen Sea embayment, West Antarctica, Geology, 37, 411–414,
2009.
Larter, R. D., Anderson, J. B., Graham, A. G. C., Gohl, K., Hillenbrand, C-.
D., Jakobsson, M., Johnson, J. S., Kuhn, G., Nitsche, F. O., Smith, J. A.,
Witus, A. E., Bentley, M. J., Dowdeswell, J. A., Ehrmann, W., Klages, J. P.,
Lindow, J., O Cofaigh, C., and Spiegel, C.: Reconstruction of changes in the
Amundsen Sea ad Bellingshausen Sea sector of the West Antarctic Ice Sheet
since the Last Glacial Maximum, Quaternary Sci. Rev., 100, 55–86,
2014.
Larter, R. D., Queste, B. Y., Boehme, L., Braddock, S., Wåhlin, A. K.,
Graham, A. G. C., Hogan, K. A., Totten Minzoni, R., Barham, M., Bortolotto
de'Oliveira, G., Clark, R., Fitzgerald, V., Karam, S., Kirkham, J. D.,
Mazur, A., Sheehan, P., Spoth, M., Stedt, P., Welzenbach, L. Zheng, Y.,
Andersson, J., Rolandsson, J., Beeler, C., Goodell, J., Rush, and Snow, T.:
CRUISE REPORT RV/IB Nathaniel B. Palmer Cruise NBP19-02, January-March 2019: First research cruise of the International Thwaites
Glacier Collaboration,
http://get.rvdata.us/cruise/NBP1902/doc/NBP1902_report_final.pdf (last access: 11 June 2020), 2020.
Larter, R. D. and Vanneste, L. E.: Relict subglacial deltas on the Antarctic
Peninsula outer shelf, Geology, 23, 33–36, 1995.
Livingstone, S. J., Cofaigh, C. Ó., Stokes, C. R., Hillenbrand, C.-D.,
Vieli, A., and Jamieson, S. S. R.: Glacial geomorphology of Marguerite Bay
Palaeo-Ice stream, western Antarctic Peninsula, J. Maps, 9, 558–572,
2013.
Liu, E. W., Räss, L., Suckale, J., Herman, F., and Podladchikov, Y.:
Spontaneous Formation of Internal Shear Zone in Ice Flowing over a
Topographically Variable Bed, EGU General Assembly 2020, Online, 4–8 May
2020, EGU2020-12602,
https://doi.org/10.5194/egusphere-egu2020-12602, 2020.
Lowe, A. L. and Anderson, J. B.: Evidence for abundant subglacial meltwater
beneath the paleo-ice sheet in Pine Island Bay, Antarctica, J. Glaciol., 49, 125–138, 2003.
Lowe, A. L. and Anderson, J. B.: Reconstruction of the West Antarctic ice
sheet in Pine Island Bay during the Last Glacial Maximum and its subsequent
retreat history, Quaternary Sci. Rev., 21, 1879–1897, 2002.
MacAyeal, D. R.: Large-scale ice flow over a viscous basal sediment: Theory
and application to ice stream B, Antarctica, J. Geophys. Res.-Sol. Ea., 94, 4071–4087, 1989.
MacGregor, J. A., Catania, G. A., Markowski, M. S., and Andrews, A. G.:
Widespread rifting and retreat of ice-shelf margins in the eastern Amundsen
Sea Embayment between 1972 and 2011, J. Glaciol., 58, 458–466,
2012.
MacLean, B., Blasco, S., Bennett, R., Hughes Clarke, J. E., and Patton, E.:
Crag-and-tail features, Amundsen Gulf, Canadian Arctic Archipelago, edited by: Dowdeswell, J. A., Canals, M., Jakobsson, M., Todd, B. J., Dowdeswell, E. K., and Hogan, K. A., Memoirs, Geological Society, London, 46, 53–54, https://doi.org/10.1144/M46.84, 2016.
Matsuoka, K., Hindmarsh, R. C. A., Moholdt, G., Bentley, M. J., Pritchard,
H. D., Brown, J., Conway, H., Drews, R., Durand., G., Goldberg, D.,
Hattermann, T., Kingslake, J., Lenaerts, J. T. M., Martín, C.,
Mulvaney, R., Nicholss, K. W., Pattyn, F., Ross, N., Scambos, T., and
Whitehouse, P. L.: Antarctic ice rises and rumples: Their properties and
significance for ice-sheet dynamics and evolution, Earth Sci. Rev.,
150, 724–745, 2015.
Mayer, L. A., Paton, M., Gee, L., Gardner, S. V., and Ware, C.: Interactive
3-D visualization: a tool for seafloor navigation, exploration and
engineering, in: Proceedings of the OCEANS 2000 MTS/IEEE Conference and Exhibition, Providence, USA, 11–14 September 200, 913–919, 2000.
McMillan, M., Shepherd, A., Sundal, A., Briggs, K., Muir, A., Ridout, A.,
Hogg, A., and Wingham, D.: Increased ice losses from Antarctica detected by
CryoSat-2, Geophys. Res. Lett., 41, 3899–3905, 2014.
Milillo, P., Rignot, E., Rizzoli, P., Scheuchl, B., Mouginot, J.,
Bueso-Bello, J., and Prats-Iraola, P.: Heterogeneous retreat and ice melt of
Thwaites Glacier, West Antarctica, Science Advances, 5, eaau3433, https://doi.org/10.1126/sciadv.aau3433, 2019.
Millan, R., Rignot, E., Bernier, V., Morlighem, M., and Dutrieux, P.:
Bathymetry of the Amundsen Sea Embayment sector of West Antarctica from
Operation IceBridge gravity and other data, Geophys. Res. Lett.,
44, 1360–1368, 2017.
Morlighem, M., Rignot, E., Binder, T., Blankenship, D., Drews, R., Eagles,
G., Eisen, O., Ferraccioli, F., Forsberg, R., Fretwell, P., Goel, V.,
Greenbaum, J. S., Gudmundsson, H., Guo, J., Helm, V., Hofstede, C., Howat,
I., Humbert, A., Jokat, W., Karlsson, N. B., Lee, W. S., Matsuoka, K.,
Millan, R., Mouginot, J., Paden, J., Pattyn, F., Roberts, J., Rosier, S.,
Ruppel, A., Seroussi, H., Smith, E. C., Steinhage, D., Sun, B., Broeke, M.
R. v. d., Ommen, T. D. v., Wessem, M. v., and Young, D. A.: Deep glacial
troughs and stabilizing ridges unveiled beneath the margins of the Antarctic
ice sheet, Nat. Geosci., 13, 132–137, https://doi.org/10.1038/s41561-019-0510-8, 2019.
Mouginot, J., Rignot, E., and Scheuchl, B.: Continent-Wide, Interferometric
SAR Phase, Mapping of Antarctic Ice Velocity, Geophys. Res. Lett.,
46, 9710–9718, 2019.
Mouginot, J., Rignot, E., and Scheuchl, B.: Sustained increase in ice
discharge from the Amundsen Sea Embayment, West Antarctica, from 1973 to
2013, Geophys. Res. Lett., 41, 1576–1584, 2014.
Muto, A., Alley, R. B., Parizek, B. R., and Anandakrishnan, S.: Bed-type
variability and till (dis)continuity beneath Thwaites Glacier, West
Antarctica, Ann. Glaciol., 60, 82–90, https://doi.org/10.1017/aog.2019.32, 2019a.
Muto, A., Anandakrishnan, S., Alley, R. B., Horgan, H. J., Parizek, B. R.,
Koellner, S., Christianson, K., and Holschuh, N.: Relating bed character and
subglacial morphology using seismic data from Thwaites Glacier, West
Antarctica, Earth Planet Sc. Lett., 507, 199–206, 2019b.
Nakayama, Y., Manucharyan, G., Zhang, H., Dutrieux, P., Torres, H. S.,
Klein, P., Seroussi, H., Schodlok, M., Rignot, E., and Menemenlis, D.:
Pathways of ocean heat towards Pine Island and Thwaites grounding lines,
Sci. Rep., 9, 16649, https://doi.org/10.1038/s41598-019-53190-6, 2019.
Nakayama, Y., Schröder, M., and Hellmer, H. H.: From circumpolar deep
water to the glacial meltwater plume on the eastern Amundsen Shelf, Deep-Sea
Res. Pt. I, 77, 50–62, 2013.
Nitsche, F. O., Gohl, K., Larter, R. D., Hillenbrand, C.-D., Kuhn, G., Smith, J. A., Jacobs, S., Anderson, J. B., and Jakobsson, M.: Paleo ice flow and subglacial meltwater dynamics in Pine Island Bay, West Antarctica, The Cryosphere, 7, 249–262, https://doi.org/10.5194/tc-7-249-2013, 2013.
Nitsche, F. O., Jacobs, S. S., Larter, R. D., and Gohl, K.: Bathymetry of
the Amundsen Sea continental shelf: Implications for geology, oceanography,
and glaciology, Geochem. Geophy. Geosy., 8, Q10009, https://doi.org/10.1029/2007GC001694, 2007.
Nitsche, F. O., Larter, R. D., Gohl, K., Graham, A. G. C., and Kuhn, G.:
Crag-and-tail features on the Amundsen Sea continental shelf, West
Antarctica, edited by: Dowdeswell, J. A., Canals, M., Jakobsson, M., Todd, B. J., Dowdeswell, E. K., and Hogan, K. A., Memoirs, Geological Society, London, 46, 199–200, https://doi.org/10.1144/M46.2, 2016.
Noormets, R., Dowdeswell, J. A., Larter, R. D., Ó Cofaigh, C., and
Evans, J.: Morphology of the upper continental slope in the Bellingshausen
and Amundsen Seas - Implications for sedimentary processes at the shelf edge
of West Antarctica, Mar. Geol., 258, 100–114, 2009.
Noormets, R., Kirchner, N., Flink, A. E., and Dowdeswell, J. A.: Possible
iceberg-produced submarine terraces in Hambergbukta, Spitsbergen, edited by: Dowdeswell, J. A., Canals, M., Jakobsson, M., Todd, B. J., Dowdeswell, E. K., and Hogan, K. A., Memoirs, Geolhttps://doi.org/10.1144/M46.121, 2016.
Nye, J. F.: Glacier sliding without cavitation in a linear viscous
approximation, P. Roy. Soc. A-Math. Phy., 315, 381–403,
1970.
Ó Cofaigh, C., Dowdeswell, J. A., Allen, C. S., Hiemstra, J. F., Pudsy,
C., J., Evans, J., Evans, D. J. A.: Flow dynamics and till genesis
associated with a marine-based Antarctic palaeo-ice stream, Quaternary Sci. Rev., 24, 709–740, 2005.
Paden, J., Akins, T., Dunson, D., Allen, C., and Gogineni, P.: Ice-sheet bed
3-D tomography, J. Glaciol., 56, 3–11, https://doi.org/10.3189/002214310791190811, 2010.
Parizek, B. R. and Walker, R. T.: Implications of initial conditions and
ice–ocean coupling for grounding-line evolution, Earth Planet Sc. Lett., 300, 351–358, 2010.
Pattyn, F. and Van Huele, W.: Power law or power flaw?, Earth Surface
Processes and Landforms, 23, 761–767, 1998.
Post, A. L., O'Brien, P. E., Edwards, S., Carroll, A. G., Malakoff, K., and
Armand, L. K.: Upper slope processes and seafloor ecosystems on the Sabrina
continental slope, East Antarctica, Mar. Geol., 422, 106091,
https://doi.org/10.1016/j.margeo.2019.106091, 2020.
Rabus, B. T., Lang, O., and Adolphs, U.: Interannual velocity variations and
recent calving of Thwaites Glacier Tongue, West Antarctica, Ann. Glaciol., 36, 215–224, 2003.
Rignot, E.: Evidence for rapid retreat and mass loss of Thwaites Glacier,
West Antarctica, J. Glaciol., 47, 213–222, 2001.
Rignot, E., Jacobs, S., Mouginot, J., and Scheuchl, B.: Ice-Shelf Melting
Around Antarctica, Science, 341, 266–270, 2013.
Rignot, E., Mouginot, J., Morlighem, M., Seroussi, H., and Scheuchl, B.:
Widespread, rapid grounding line retreat of Pine Island, Thwaites, Smith,
and Kohler glaciers, West Antarctica, from 1992 to 2011, Geophys. Res. Lett., 41, 3502–3509, 2014.
Rignot, E., Mouginot, J., and Scheuchl, B.: Antarctic grounding line mapping
from differential satellite radar interferometry, Geophys. Res. Lett., 38, L10504, https://doi.org/10.1029/2011GL047109, 2011.
Rignot, E., Mouginot, J., Scheuchl, B., van den Broeke, M., van Wessem, M.
J., and Morlighem, M.: Four decades of Antarctic Ice Sheet mass balance from
1979–2017, P. Natl. Acad. Sci. USA, 116, 1095,
2019.
Rippin, D. M., Vaughan, D. G., and Corr, H. F. J.: The basal roughness of
Pine Island Glacier, West Antarctica, J. Glaciol., 57, 67–76,
2011.
Scambos, T. A., Bell, R. E., Alley, R. B., Anandakrishnan, S., Bromwich, D.
H., Brunt, K., Christianson, K., Creyts, T., Das, S. B., DeConto, R.,
Dutrieux, P., Fricker, H. A., Holland, D., MacGregor, J., Medley, B.,
Nicolas, J. P., Pollard, D., Siegfried, M. R., Smith, A. M., Steig, E. J.,
Trusel, L. D., Vaughan, D. G., and Yager, P. L.: How much, how fast?: A
science review and outlook for research on the instability of Antarctica's
Thwaites Glacier in the 21st century, Global Planet. Change, 153,
16–34, 2017.
Schoof, C.: Basal perturbations under ice streams: form drag and surface
expression, J. Glaciol., 48, 407–416, 2002.
Schoof, C.: The effect of cavitation on glacier sliding, P. Roy. Soc. A-Math. Phy., 461,
609–627, 2005.
Schoof, C.: Ice sheet grounding line dynamics: Steady states, stability, and
hysteresis, J. Geophys. Res.-Earth, 112, F03S28,
https://doi.org/10.1029/2006JF000664, 2007.
Schroeder, D. M., Blankenship, D. D., and Young, D. A.: Evidence for a water
system transition beneath Thwaites Glacier, West Antarctica, P. Natl. Acad. Sci. USA, 110, 12225, 2013.
Schroeder, D. M., Blankenship, D. D., Young, D. A., Witus, A. E., and
Anderson, J. B.: Airborne radar sounding evidence for deformable sediments
and outcropping bedrock beneath Thwaites Glacier, West Antarctica,
Geophys. Res. Lett., 41, 7200–7208, 2014.
Shepherd, A., Gilbert, L., Muir, A. S., Konrad, H., McMillan, M., Slater,
T., Briggs, K. H., Sundal, A. V., Hogg, A. E., and Engdahl, M. E.: Trends in
Antarctic Ice Sheet Elevation and Mass, Geophys. Res. Lett., 46,
8174–8183, 2019.
Siegert, M. J., Taylor, J., Payne, A. J., and Hubbard, B.: Macro-scale bed
roughness of the Siple Coast ice streams in west Antarctica, Earth Surface
Processes and Landforms, 29, 1591–1596, 2004.
Spagnolo, M., Clark, C. D., Ely, J. C., Stokes, C. R., Anderson, J. B.,
Andreassen, K., Graham, A. G. C., and King, E. C.: Size, shape and spatial
arrangement of mega-scale glacial lineations from a large and diverse
dataset, Earth Surface Processes and Landforms, 39, 1432–1448, 2014.
Spagnolo, M., Bartholomaus, T. C., Clark, C. D., Stokes, C. R., Atkinson,
N., Dowdeswell, J. A., Ely, J. C., Graham, A. G. C., Hogan, K. A., King, E.
C., Larter, R. D., Livingstone, S. J., and Pritchard, H. D.: The periodic
topography of ice stream beds: Insights from the Fourier spectra of
mega-scale glacial lineations, J. Geophys. Res.-Earth, 122, 1355–1373, 2017.
Spiegel, C., Lindow, J., Kamp, P. J. J., Meisel, O., Mukasa, S., Lisker, F.,
Kuhn, G., and Gohl, K.: Tectonomorphic evolution of Marie Byrd Land –
Implications for Cenozoic rifting activity and onset of West Antarctic
glaciation, Global Planet. Change, 145, 98–115, 2016.
Tinto, K. J. and Bell, R. E.: Progressive unpinning of Thwaites Glacier from
newly identified offshore ridge: Constraints from aerogravity, Geophys. Res. Lett., 38, L20503, https://doi.org/10.1029/2011GL049026, 2011.
Tinto, K., Bell, R. E., and Cochran, J. R.: IceBridge Sander AIRGrav L1B Geolocated Free Air Gravity Anomalies, Version 1.05, NASA National Snow and Ice Data Center Distributed Active Archive Center, Boulder, Colorado USA, https://doi.org/10.5067/R1RQ6NRIJV89, 2010 (updated 2019).
Vanneste, M., Mienert, J., and Bünz, S.: The Hinlopen Slide: A giant,
submarine slope failure on the northern Svalbard margin, Arctic Ocean, Earth Planet Sc. Lett., 245, 373–388, 2006.
Vaughan, D. G. and Arthern, R.: Why Is It Hard to Predict the Future of Ice
Sheets?, Science, 315, 1503, 2007.
Vaughan, D. G., Smith, A.M., Corr, H. F. J., Jenkins, A., Bentley, C. R., Stenoien, M. D., Jacobs, S. S., Kellogg, T. B., Rignot, E., and Lucchitta, B. K.: A Review of Pine Island Glacier, West Antarctica: Hypotheses of Instability vs. Observations of Change, American Geophysical Union, Washington, D.C., Antarctic Research Series, 77, 237–256, 2001.
Vogt, P. R., Crane, K., and Sundvor, E.: Deep Pleistocene iceberg plowmarks
on the Yermak Plateau: sidescan and 3.5 kHz evidence for thick calving ice
fronts and a possible marine ice sheet in the Arctic Ocean, Geology, 22,
403–406, 1994.
Walker, D. P., Brandon, M. A., Jenkins, A., Allen, J. T., Dowdeswell, J. A.,
and Evans, J.: Oceanic heat transport onto the Amundsen Sea shelf through a
submarine glacial trough, Geophys. Res. Lett., 34, L02602, https://doi.org/10.1029/2006GL028154, 2007.
Weertman, J.: On the Sliding of Glaciers, J. Glaciol., 3, 33–38,
1957.
Weertman, J.: Stability of the junction between an ice sheet and an ice
shelf, J. Glaciol., 13, 3–11, 1974.
Welch, P. D.: The Use of Fast Fourier Transform for the Estimation of Power
Spectra: A Method Based on Time Averaging Over Short, Modified Periodograms,
IEEE T. Acoust. Speech., 15, 70–73, 1967.
Wellner, J. S., Heroy, D. C., and Anderson, J. B.: The death mask of the
Antarctic ice sheet: Comparison of glacial geomorphic features across the
continental shelf, Geomorphology, 75, 157–171, 2006.
Whitehouse, P. L., Bentley, M. J., Milne, G. A., King, M. A. and Thomas, I.
D.: A new glacial isostatic adjustment model for Antarctica: calibrated and
tested using observations of relative sea-level change and present-day
uplift rates, Geophys. J. Int., 190, 1464–1482, 2012.
Short summary
The sea-floor geometry around the rapidly changing Thwaites Glacier is a key control on warm ocean waters reaching the ice shelf and grounding zone beyond. This area was previously unsurveyed due to icebergs and sea-ice cover. The International Thwaites Glacier Collaboration mapped this area for the first time in 2019. The data reveal troughs over 1200 m deep and, as this region is thought to have only ungrounded recently, provide key insights into the morphology beneath the grounded ice sheet.
The sea-floor geometry around the rapidly changing Thwaites Glacier is a key control on warm...
