Articles | Volume 16, issue 12
https://doi.org/10.5194/tc-16-5085-2022
© Author(s) 2022. 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-16-5085-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Dec 2022
Research article |
| 22 Dec 2022
| 22 Dec 2022
Anthropogenic and internal drivers of wind changes over the Amundsen Sea, West Antarctica, during the 20th and 21st centuries
Paul R. Holland
CORRESPONDING AUTHOR
British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Gemma K. O'Connor
Department of Earth and Space Sciences, University of Washington, Seattle, Washington, USA
Thomas J. Bracegirdle
British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Pierre Dutrieux
British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Kaitlin A. Naughten
British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
Eric J. Steig
Department of Earth and Space Sciences, University of Washington, Seattle, Washington, USA
Department of Atmospheric Sciences, University of Washington, Seattle, Washington, USA
David P. Schneider
National Center for Atmospheric Research, Boulder, Colorado, USA
Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA
Adrian Jenkins
Department of Geography and Environmental Sciences, Northumbria University, Newcastle, UK
James A. Smith
British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
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Daniel N. Goldberg, Paul R. Holland, and Kaitlin A. Naughten
EGUsphere, https://doi.org/10.5194/egusphere-2026-3779, https://doi.org/10.5194/egusphere-2026-3779, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
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Antarctica’s Amundsen Sea glaciers are major contributors to sea-level rise. Using multi-century, high-resolution coupled ice–ocean simulations of the region, we show that 21st century predictions depend strongly on how ice-sheet models are initialized, especially for Thwaites Glacier. By the 22nd century, however, ocean warming becomes the dominant driver, leading to much faster ice loss under high-emissions scenarios, highlighting the importance of improving coupled climate–ice models.
Alexander T. Bradley, David T. Bett, C. Rosie Williams, Robert J. Arthern, Paul R. Holland, James Byrne, Tamsin L. Edwards, and Mira Adhikari
The Cryosphere, 20, 3443–3465, https://doi.org/10.5194/tc-20-3443-2026, https://doi.org/10.5194/tc-20-3443-2026, 2026
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At least since we began measuring in detail, the West Antarctic Ice Sheet has lost a lot of ice, but we don't know precisely how important climate change is in this. Here, 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.
Anna Olivé Abelló, Pierre Mathiot, Nicolas C. Jourdain, Yavor Kostov, and Paul R. Holland
EGUsphere, https://doi.org/10.5194/egusphere-2026-3422, https://doi.org/10.5194/egusphere-2026-3422, 2026
This preprint is open for discussion and under review for Ocean Science (OS).
Short summary
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Antarctic icebergs release large amounts of freshwater, but models often add it entirely at the ocean surface. Using simulations with drifting icebergs, we assessed whether releasing meltwater at depth alters the Southern Ocean's response. Most meltwater remained in the surface mixed layer, and deeper release caused only weak, local changes in the ocean, sea ice and ice shelf melting. Hence, surface release remains a reasonable approach for large-scale studies, though depth matters regionally.
Paul Holland, Adrian Jenkins, David Bett, and Suzanne Bevan
EGUsphere, https://doi.org/10.5194/egusphere-2026-2835, https://doi.org/10.5194/egusphere-2026-2835, 2026
Short summary
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Ice loss from the Amundsen Sea sector of the Antarctic Ice Sheet is a major contributor to global sea-level rise. In this study we use ocean simulations to understand the ice melting in this sector. The strongest melting is focussed on deep ice where the glaciers flow into the ocean. Secondary areas of melting occur beneath meltwater currents. The simulations are used to test simple mathematical representations of melting that could be built into an ice sheet model.
Robin S. Smith, Tarkan A. Bilge, Thomas J. Bracegirdle, Paul R. Holland, Till Kuhlbrodt, Charlotte Lang, Spencer Liddicoat, Tom Mitcham, Jane Mulcahy, Kaitlin A. Naughten, Andrew Orr, Julien Palmieri, Antony J. Payne, Steven Rumbold, Marc Stringer, Ranjini Swaminathan, Sarah Taylor, Jeremy Walton, and Colin Jones
Earth Syst. Dynam., 17, 475–493, https://doi.org/10.5194/esd-17-475-2026, https://doi.org/10.5194/esd-17-475-2026, 2026
Short summary
Short summary
There is a dangerous amount of uncertainty in our predictions of climate change in polar regions because some of feedbacks that might lead to changes that are too rapid for us to adapt to, or that cannot be reversed. We have run a set of simulations with a state-of-the-art Earth System Model that helps improve our understanding of how climate in these regions might change. Some of the aspects we investigate are reversible but many are not, especially those affecting ice sheets and sea level.
Claire K. Yung, Xylar S. Asay-Davis, Alistair Adcroft, Christopher Y. S. Bull, Jan De Rydt, Michael S. Dinniman, Benjamin K. Galton-Fenzi, Daniel Goldberg, David E. Gwyther, Robert Hallberg, Matthew Harrison, Tore Hattermann, David M. Holland, Denise Holland, Paul R. Holland, James R. Jordan, Nicolas C. Jourdain, Kazuya Kusahara, Gustavo Marques, Pierre Mathiot, Dimitris Menemenlis, Adele K. Morrison, Yoshihiro Nakayama, Olga Sergienko, Robin S. Smith, Alon Stern, Ralph Timmermann, and Qin Zhou
The Cryosphere, 20, 2053–2088, https://doi.org/10.5194/tc-20-2053-2026, https://doi.org/10.5194/tc-20-2053-2026, 2026
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The second Ice Shelf-Ocean Model Intercomparison Project, ISOMIP+, compares 12 ice shelf-ocean models with a common, idealised, static configuration, aiming to assess inter-model variability. Models show similar basal melt rate patterns, ocean profiles and circulation but differ in ice-ocean boundary layer properties. Ice-ocean boundary layer representation is a key area for future work, as are realistic-domain ice sheet-ocean model intercomparisons.
David T. Bett, Alexander T. Bradley, Bertie W. J. Miles, C. Rosie Williams, Paul R. Holland, and Robert J. Arthern
EGUsphere, https://doi.org/10.5194/egusphere-2026-669, https://doi.org/10.5194/egusphere-2026-669, 2026
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An ice-ocean model is used to explore the 20th-century evolution of Thwaites Glacier, Antarctica. Several processes are involved as the ice retreats to its present-day state, including ocean melting, the floatation of a historically-grounded ice island, ice crevassing and damage, and changing of ice-flow patterns. Multiple options for steady historical Thwaites Glacier configurations are found, with these options compared against 1940s aerial imagery and evidence from seabed sediments.
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
The Cryosphere, 20, 135–169, https://doi.org/10.5194/tc-20-135-2026, https://doi.org/10.5194/tc-20-135-2026, 2026
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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.
Gavin A. Schmidt, Kenneth D. Mankoff, Jonathan L. Bamber, Clara Burgard, Dustin Carroll, David M. Chandler, Violaine Coulon, Benjamin J. Davison, Matthew H. England, Paul R. Holland, Nicolas C. Jourdain, Qian Li, Juliana M. Marson, Pierre Mathiot, Clive R. McMahon, Twila A. Moon, Ruth Mottram, Sophie Nowicki, Anna Olivé Abelló, Andrew G. Pauling, Thomas Rackow, and Damien Ringeisen
Geosci. Model Dev., 18, 8333–8361, https://doi.org/10.5194/gmd-18-8333-2025, https://doi.org/10.5194/gmd-18-8333-2025, 2025
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The impact of increasing mass loss from the Greenland and Antarctic ice sheets has not so far been included in historical climate model simulations. This paper describes the protocols and data available for modeling groups to add this anomalous freshwater to their ocean modules to better represent the impacts of these fluxes on ocean circulation, sea ice, salinity and sea level.
Katie Lowery, Pierre Dutrieux, Paul R. Holland, Anna E. Hogg, Noel Gourmelen, and Benjamin J. Wallis
The Cryosphere, 19, 4893–4911, https://doi.org/10.5194/tc-19-4893-2025, https://doi.org/10.5194/tc-19-4893-2025, 2025
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Using CryoSat-2, we observe monthly changes in the Pine Island Glacier (PIG) ice shelf surface and derive oceanic melt at its base. Basal channels, kilometres wide, are reflected in the ice surface and captured in our observations. We demonstrate that melt is concentrated on the western walls of channels, that channels play a role in grounding pinning points, and that PIG's main channel geometry is inherited upstream of the grounding line. These results highlight the importance of channels to ice shelf stability.
Caroline R. Holmes, Thomas J. Bracegirdle, Paul R. Holland, Julienne Stroeve, and Jeremy Wilkinson
The Cryosphere, 18, 5641–5652, https://doi.org/10.5194/tc-18-5641-2024, https://doi.org/10.5194/tc-18-5641-2024, 2024
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Until recently, satellite data showed an increase in Antarctic sea ice area since 1979, but climate models simulated a decrease over this period. This mismatch was one reason for low confidence in model projections of 21st-century sea ice loss. We show that following low Antarctic sea ice in 2022 and 2023, we can no longer conclude that modelled and observed trends differ. However, differences in the manner of the decline mean that model sea ice projections should still be viewed with caution.
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
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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.
Gemma K. O'Connor, Paul R. Holland, Eric J. Steig, Pierre Dutrieux, and Gregory J. Hakim
The Cryosphere, 17, 4399–4420, https://doi.org/10.5194/tc-17-4399-2023, https://doi.org/10.5194/tc-17-4399-2023, 2023
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Glaciers in West Antarctica are rapidly melting, but the causes are unknown due to limited observations. A leading hypothesis is that an unusually large wind event in the 1940s initiated the ocean-driven melting. Using proxy reconstructions (e.g., using ice cores) and climate model simulations, we find that wind events similar to the 1940s event are relatively common on millennial timescales, implying that ocean variability or climate trends are also necessary to explain the start of ice loss.
Erwin Lambert, André Jüling, Roderik S. W. van de Wal, and Paul R. Holland
The Cryosphere, 17, 3203–3228, https://doi.org/10.5194/tc-17-3203-2023, https://doi.org/10.5194/tc-17-3203-2023, 2023
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A major uncertainty in the study of sea level rise is the melting of the Antarctic ice sheet by the ocean. Here, we have developed a new model, named LADDIE, that simulates this ocean-driven melting of the floating parts of the Antarctic ice sheet. This model simulates fine-scale patterns of melting and freezing and requires significantly fewer computational resources than state-of-the-art ocean models. LADDIE can be used as a new tool to force high-resolution ice sheet models.
Antony Siahaan, Robin S. Smith, Paul R. Holland, Adrian Jenkins, Jonathan M. Gregory, Victoria Lee, Pierre Mathiot, Antony J. Payne, Jeff K. Ridley, and Colin G. Jones
The Cryosphere, 16, 4053–4086, https://doi.org/10.5194/tc-16-4053-2022, https://doi.org/10.5194/tc-16-4053-2022, 2022
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The UK Earth System Model is the first to fully include interactions of the atmosphere and ocean with the Antarctic Ice Sheet. Under the low-greenhouse-gas SSP1–1.9 (Shared Socioeconomic Pathway) scenario, the ice sheet remains stable over the 21st century. Under the strong-greenhouse-gas SSP5–8.5 scenario, the model predicts strong increases in melting of large ice shelves and snow accumulation on the surface. The dominance of accumulation leads to a sea level fall at the end of the century.
Daniel N. Goldberg, Paul R. Holland, and Kaitlin A. Naughten
EGUsphere, https://doi.org/10.5194/egusphere-2026-3779, https://doi.org/10.5194/egusphere-2026-3779, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Antarctica’s Amundsen Sea glaciers are major contributors to sea-level rise. Using multi-century, high-resolution coupled ice–ocean simulations of the region, we show that 21st century predictions depend strongly on how ice-sheet models are initialized, especially for Thwaites Glacier. By the 22nd century, however, ocean warming becomes the dominant driver, leading to much faster ice loss under high-emissions scenarios, highlighting the importance of improving coupled climate–ice models.
Alexander T. Bradley, David T. Bett, C. Rosie Williams, Robert J. Arthern, Paul R. Holland, James Byrne, Tamsin L. Edwards, and Mira Adhikari
The Cryosphere, 20, 3443–3465, https://doi.org/10.5194/tc-20-3443-2026, https://doi.org/10.5194/tc-20-3443-2026, 2026
Short summary
Short summary
At least since we began measuring in detail, the West Antarctic Ice Sheet has lost a lot of ice, but we don't know precisely how important climate change is in this. Here, 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.
Anna Olivé Abelló, Pierre Mathiot, Nicolas C. Jourdain, Yavor Kostov, and Paul R. Holland
EGUsphere, https://doi.org/10.5194/egusphere-2026-3422, https://doi.org/10.5194/egusphere-2026-3422, 2026
This preprint is open for discussion and under review for Ocean Science (OS).
Short summary
Short summary
Antarctic icebergs release large amounts of freshwater, but models often add it entirely at the ocean surface. Using simulations with drifting icebergs, we assessed whether releasing meltwater at depth alters the Southern Ocean's response. Most meltwater remained in the surface mixed layer, and deeper release caused only weak, local changes in the ocean, sea ice and ice shelf melting. Hence, surface release remains a reasonable approach for large-scale studies, though depth matters regionally.
Luisa E. Avilés-Podgurski, Patrick Martineau, Hua Lu, Ayako Yamamoto, Amanda C. Maycock, Andrew Orr, Tony Phillips, Thomas J. Bracegirdle, Anna E. Hogg, Grzegorz Muszynski, and Andrew Fleming
Weather Clim. Dynam., 7, 1051–1071, https://doi.org/10.5194/wcd-7-1051-2026, https://doi.org/10.5194/wcd-7-1051-2026, 2026
Short summary
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Atmospheric rivers (ARs) are narrow filaments of intense poleward water vapour transport. On rare occasions, they reach the Arctic, driving strong warming and melt. In April 2020, two ARs intruded into the central Arctic within one week, raising near-surface temperatures by up to 30°C and leading to extreme precipitation. Their distinct paths and thermodynamic evolution reveal diverse AR impacts on Arctic sea ice and precipitation extremes.
Paul Holland, Adrian Jenkins, David Bett, and Suzanne Bevan
EGUsphere, https://doi.org/10.5194/egusphere-2026-2835, https://doi.org/10.5194/egusphere-2026-2835, 2026
Short summary
Short summary
Ice loss from the Amundsen Sea sector of the Antarctic Ice Sheet is a major contributor to global sea-level rise. In this study we use ocean simulations to understand the ice melting in this sector. The strongest melting is focussed on deep ice where the glaciers flow into the ocean. Secondary areas of melting occur beneath meltwater currents. The simulations are used to test simple mathematical representations of melting that could be built into an ice sheet model.
Robin S. Smith, Tarkan A. Bilge, Thomas J. Bracegirdle, Paul R. Holland, Till Kuhlbrodt, Charlotte Lang, Spencer Liddicoat, Tom Mitcham, Jane Mulcahy, Kaitlin A. Naughten, Andrew Orr, Julien Palmieri, Antony J. Payne, Steven Rumbold, Marc Stringer, Ranjini Swaminathan, Sarah Taylor, Jeremy Walton, and Colin Jones
Earth Syst. Dynam., 17, 475–493, https://doi.org/10.5194/esd-17-475-2026, https://doi.org/10.5194/esd-17-475-2026, 2026
Short summary
Short summary
There is a dangerous amount of uncertainty in our predictions of climate change in polar regions because some of feedbacks that might lead to changes that are too rapid for us to adapt to, or that cannot be reversed. We have run a set of simulations with a state-of-the-art Earth System Model that helps improve our understanding of how climate in these regions might change. Some of the aspects we investigate are reversible but many are not, especially those affecting ice sheets and sea level.
Abigail Hudak, Asmita Banerjee, Christo Buizert, Edward Brook, Michael Kalk, Lindsey Davidge, Andrew J. Schauer, Eric J. Steig, Noah Brown, Liam Kirkpatrick, John-Morgan Manos, Jacob I. Chalif, Erich Osterberg, Miranda Helena Miranda, Eric Saltzman, Yuzhen Yan, Valens Hishamunda, and John Higgins
EGUsphere, https://doi.org/10.5194/egusphere-2026-2045, https://doi.org/10.5194/egusphere-2026-2045, 2026
This preprint is open for discussion and under review for Climate of the Past (CP).
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The Allan Hills contains the oldest known ice, extending records millions of years, however, this area along the Transantarctic Mountains margin results in stratigraphically discontinuous ice core records. Here, we investigate high-resolution geochemical records to better constrain biases and stratigraphic complexities, and find these records exhibit reduced variance, some degree of interglacial bias, with varying behaviours across ice cores at the Allan Hills.
Claire K. Yung, Xylar S. Asay-Davis, Alistair Adcroft, Christopher Y. S. Bull, Jan De Rydt, Michael S. Dinniman, Benjamin K. Galton-Fenzi, Daniel Goldberg, David E. Gwyther, Robert Hallberg, Matthew Harrison, Tore Hattermann, David M. Holland, Denise Holland, Paul R. Holland, James R. Jordan, Nicolas C. Jourdain, Kazuya Kusahara, Gustavo Marques, Pierre Mathiot, Dimitris Menemenlis, Adele K. Morrison, Yoshihiro Nakayama, Olga Sergienko, Robin S. Smith, Alon Stern, Ralph Timmermann, and Qin Zhou
The Cryosphere, 20, 2053–2088, https://doi.org/10.5194/tc-20-2053-2026, https://doi.org/10.5194/tc-20-2053-2026, 2026
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The second Ice Shelf-Ocean Model Intercomparison Project, ISOMIP+, compares 12 ice shelf-ocean models with a common, idealised, static configuration, aiming to assess inter-model variability. Models show similar basal melt rate patterns, ocean profiles and circulation but differ in ice-ocean boundary layer properties. Ice-ocean boundary layer representation is a key area for future work, as are realistic-domain ice sheet-ocean model intercomparisons.
Brad Reed, Jan De Rydt, Kaitlin A. Naughten, and Daniel N. Goldberg
EGUsphere, https://doi.org/10.5194/egusphere-2026-931, https://doi.org/10.5194/egusphere-2026-931, 2026
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Melting beneath Antarctic ice shelves drives ice loss and raises sea levels, but the computer models we use to predict this are poorly constrained. We improved how these models are set up by using multiple real-world observations of ice thinning and glacier speed, rather than melt rates alone. This better captures how the ice and ocean interact. Our projections show this approach adds 14 mm of extra sea-level rise by 2100, which is more than switching to a warmer climate scenario alone.
William J. Dow, Amanda C. Maycock, Andrew N. Ross, Ryan S. Williams, and Thomas J. Bracegirdle
EGUsphere, https://doi.org/10.5194/egusphere-2026-1179, https://doi.org/10.5194/egusphere-2026-1179, 2026
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This study aims to advance understanding of the atmospheric drivers of extreme warm days across the Antarctic Peninsula during summer. We find that these days are linked to a range of large-scale atmospheric circulation patterns. Using a statistical method, we grouped similar events and compared their wind, temperature and pressure features, showing clear differences spatially and temporally. Understanding these dynamics improves understanding of the processes that drive these extreme events.
David T. Bett, Alexander T. Bradley, Bertie W. J. Miles, C. Rosie Williams, Paul R. Holland, and Robert J. Arthern
EGUsphere, https://doi.org/10.5194/egusphere-2026-669, https://doi.org/10.5194/egusphere-2026-669, 2026
Short summary
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An ice-ocean model is used to explore the 20th-century evolution of Thwaites Glacier, Antarctica. Several processes are involved as the ice retreats to its present-day state, including ocean melting, the floatation of a historically-grounded ice island, ice crevassing and damage, and changing of ice-flow patterns. Multiple options for steady historical Thwaites Glacier configurations are found, with these options compared against 1940s aerial imagery and evidence from seabed sediments.
Morven Muilwijk, Tore Hattermann, Rebecca L. Beadling, Neil C. Swart, Aleksi Nummelin, Chuncheng Guo, David M. Chandler, Petra M. Langebroek, Shenjie Zhou, Pierre Dutrieux, Jia-Jia Chen, Christopher Danek, Matthew H. England, Stephen M. Griffies, F. Alexander Haumann, André Jüling, Ombeline Jouet, Qian Li, Torge Martin, John Marshall, Andrew G. Pauling, Ariaan Purich, Zihan Song, Inga J. Smith, Max Thomas, Irene Trombini, Eveline C. van der Linden, and Xiaoqi Xu
The Cryosphere, 20, 1087–1117, https://doi.org/10.5194/tc-20-1087-2026, https://doi.org/10.5194/tc-20-1087-2026, 2026
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Antarctic meltwater affects ocean stratification and temperature, which in turn influences the rate of ice shelf melting – a coupling missing in most climate models. We analyze a suite of climate models with added meltwater to explore this feedback in different regions. While meltwater generally enhances ocean warming and melt, in West Antarctica most models simulate coastal cooling, suggesting a negative feedback that could slow future ice loss there.
Yoshihiro Nakayama, Shuntaro Hyogo, Yichen Lin, Taewook Park, Jinho Lee, Juistine Caillet, Gobishankar Mohan, Mattia Poinelli, Pierre Dutrieux, Kazuki Nakata, Hong Zhang, Brice Loose, and Lauren Kowalski
EGUsphere, https://doi.org/10.5194/egusphere-2025-5958, https://doi.org/10.5194/egusphere-2025-5958, 2026
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We develop a regional ocean model of the Amundsen and Bellingshausen Seas in Antarctica. Differences in model setups and parameter choices often limit usability and broader scientific application, especially for non-ocean modellers. We carefully evaluate the model outputs and establish a common control experiment that can be shared and applied across studies with tracer and particle applications. This effort aims to support wide community use and improve understanding of ice–ocean interactions.
Archie Cable, Thomas Caton Harrison, Elizabeth Kent, Richard Cornes, and Thomas J. Bracegirdle
Weather Clim. Dynam., 7, 247–262, https://doi.org/10.5194/wcd-7-247-2026, https://doi.org/10.5194/wcd-7-247-2026, 2026
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Winds around the Antarctic coast have global importance. With influences from competing drivers, their structure is complex so it is hard to understand how they will change in the future. We develop a simple measure that identifies key features in the coastal winds, including their northern extent. Using climate models, we analyse future projections of this boundary and find that it will shift polewards, shrinking the Antarctic coastal wind region.
Kevin Hank, Robert J. Arthern, C. Rosie Williams, Alex M. Brisbourne, Andrew M. Smith, James A. Smith, Anna Wåhlin, and Sridhar Anandakrishnan
The Cryosphere, 20, 495–510, https://doi.org/10.5194/tc-20-495-2026, https://doi.org/10.5194/tc-20-495-2026, 2026
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The slipperiness at the ice base is a key uncertainty in sea level rise projections. Alternative formulations of the sliding law exist, but limited access to the ice base makes it difficult to validate them. We introduce a new approach using observations and model output to infer a basal sliding law. For Pine Island Glacier, currently the largest single contributor to sea level rise in Antarctica, the results provide support for a Coulomb-type sliding law and widespread low effective pressures.
Tom A. Jordan, Karen J. Heywood, Anna Wåhlin, Rob A. Hall, Atsuhiro Muto, Pierre Dutrieux, Kelly Hogan, James Girton, Karen E. Alley, and Erin Pettit
EGUsphere, https://doi.org/10.5194/egusphere-2025-6001, https://doi.org/10.5194/egusphere-2025-6001, 2026
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The shape of the water filled cavity hidden beneath ice shelves is extremely important, but hard to measure. Gravity data collected from aircraft can be used to predict the shape. However, in the Dotson Crosson ice shelves in West Antarctica, new direct observations from autonomous platforms sent beneath the ice, and seismic observations from the ice surface showed gravity models were systematically too shallow. We explain why and provide a solution applicable her and in other ice shelves.
Shenjie Zhou, Pierre Dutrieux, Claudia Giulivi, Andrew Meijers, Won Sang Lee, Tae-Wan Kim, Tore Hattermann, and Markus Janout
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-727, https://doi.org/10.5194/essd-2025-727, 2026
Revised manuscript not accepted
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A collection of temperature and salinity measurements made in the Southern Ocean and around Antarctic continental shelf seas is assembled and described in this paper. A gridded product developed out of these scattered data points is also described. The gridded product provide us a better view of contemporary mean status of the Southern Ocean and Antarctic shelf seas and help models to better reference the prediction of the future climate.
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
The Cryosphere, 20, 135–169, https://doi.org/10.5194/tc-20-135-2026, https://doi.org/10.5194/tc-20-135-2026, 2026
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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.
Benjamin K. Galton-Fenzi, Richard Porter-Smith, Sue Cook, Eva Cougnon, David E. Gwyther, Wilma G. C. Huneke, Madelaine G. Rosevear, Xylar Asay-Davis, Fabio Boeira Dias, Michael S. Dinniman, David Holland, Kazuya Kusahara, Kaitlin A. Naughten, Keith W. Nicholls, Charles Pelletier, Ole Richter, Hélène Seroussi, and Ralph Timmermann
The Cryosphere, 19, 6507–6525, https://doi.org/10.5194/tc-19-6507-2025, https://doi.org/10.5194/tc-19-6507-2025, 2025
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Quantifying melt and freeze beneath Antarctica’s floating ice shelves is vital to understanding present-day ice-sheet behavior and its potential to contribute to future sea-level rise. We compare 10 ice-shelf/ocean computer simulations with satellite data, providing the first multi-model estimate of melting and refreezing driven by the ocean. This new estimate offers a valuable tool for assessing ice-shelf roles in current and future ice-sheet changes, informing coastal adaptation strategies.
Gavin A. Schmidt, Kenneth D. Mankoff, Jonathan L. Bamber, Clara Burgard, Dustin Carroll, David M. Chandler, Violaine Coulon, Benjamin J. Davison, Matthew H. England, Paul R. Holland, Nicolas C. Jourdain, Qian Li, Juliana M. Marson, Pierre Mathiot, Clive R. McMahon, Twila A. Moon, Ruth Mottram, Sophie Nowicki, Anna Olivé Abelló, Andrew G. Pauling, Thomas Rackow, and Damien Ringeisen
Geosci. Model Dev., 18, 8333–8361, https://doi.org/10.5194/gmd-18-8333-2025, https://doi.org/10.5194/gmd-18-8333-2025, 2025
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The impact of increasing mass loss from the Greenland and Antarctic ice sheets has not so far been included in historical climate model simulations. This paper describes the protocols and data available for modeling groups to add this anomalous freshwater to their ocean modules to better represent the impacts of these fluxes on ocean circulation, sea ice, salinity and sea level.
Shenjie Zhou, Pierre Dutrieux, Claudia F. Giulivi, Adrian Jenkins, Alessandro Silvano, Christopher Auckland, E. Povl Abrahamsen, Michael Meredith, Irena Vaňková, Keith Nicholls, Peter E. D. Davis, Svein Østerhus, Arnold L. Gordon, Christopher J. Zappa, Tiago S. Dotto, Ted Scambos, Kathryn 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, 17, 5693–5706, https://doi.org/10.5194/essd-17-5693-2025, https://doi.org/10.5194/essd-17-5693-2025, 2025
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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.
Katie Lowery, Pierre Dutrieux, Paul R. Holland, Anna E. Hogg, Noel Gourmelen, and Benjamin J. Wallis
The Cryosphere, 19, 4893–4911, https://doi.org/10.5194/tc-19-4893-2025, https://doi.org/10.5194/tc-19-4893-2025, 2025
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Using CryoSat-2, we observe monthly changes in the Pine Island Glacier (PIG) ice shelf surface and derive oceanic melt at its base. Basal channels, kilometres wide, are reflected in the ice surface and captured in our observations. We demonstrate that melt is concentrated on the western walls of channels, that channels play a role in grounding pinning points, and that PIG's main channel geometry is inherited upstream of the grounding line. These results highlight the importance of channels to ice shelf stability.
David P. Schneider, Ziqi Yin, Gemma K. O'Connor, Edward Blanchard-Wrigglesworth, Zaria I. Cast, Rajashree Tri Datta, and Zachary I. Espinosa
EGUsphere, https://doi.org/10.5194/egusphere-2025-3666, https://doi.org/10.5194/egusphere-2025-3666, 2025
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Snow accumulation on the Antarctic Ice Sheet could increase with greenhouse warming, storing water that would otherwise raise sea level. Employing multiple Earth system model simulations and reconstructions, we detect a warming-driven increase in accumulation consistent with greenhouse gas forcing, but observations can only be matched if wind and meltwater impacts on large-scale surface warming patterns are accounted for, pointing to a need to include these impacts in future projections.
Sebastian H. R. Rosier, G. Hilmar Gudmundsson, Adrian Jenkins, and Kaitlin A. Naughten
The Cryosphere, 19, 2527–2557, https://doi.org/10.5194/tc-19-2527-2025, https://doi.org/10.5194/tc-19-2527-2025, 2025
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Glaciers in the Amundsen Sea region of Antarctica have been retreating and losing mass, but their future contribution to global sea level rise remains highly uncertain. We use an ice sheet model and uncertainty quantification methods to evaluate the probable range of mass loss from this region for two future climate scenarios. We find that the rate of ice loss until 2100 will likely remain similar to present-day observations, with little sensitivity to climate scenario over this short time frame.
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
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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.
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
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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.
Caroline R. Holmes, Thomas J. Bracegirdle, Paul R. Holland, Julienne Stroeve, and Jeremy Wilkinson
The Cryosphere, 18, 5641–5652, https://doi.org/10.5194/tc-18-5641-2024, https://doi.org/10.5194/tc-18-5641-2024, 2024
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Until recently, satellite data showed an increase in Antarctic sea ice area since 1979, but climate models simulated a decrease over this period. This mismatch was one reason for low confidence in model projections of 21st-century sea ice loss. We show that following low Antarctic sea ice in 2022 and 2023, we can no longer conclude that modelled and observed trends differ. However, differences in the manner of the decline mean that model sea ice projections should still be viewed with caution.
Mira Berdahl, Gunter R. Leguy, William H. Lipscomb, Bette L. Otto-Bliesner, Esther C. Brady, Robert A. Tomas, Nathan M. Urban, Ian Miller, Harriet Morgan, and Eric J. Steig
Clim. Past, 20, 2349–2371, https://doi.org/10.5194/cp-20-2349-2024, https://doi.org/10.5194/cp-20-2349-2024, 2024
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Studying climate conditions near the Antarctic ice sheet (AIS) during Earth’s past warm periods informs us about how global warming may influence AIS ice loss. Using a global climate model, we investigate climate conditions near the AIS during the Last Interglacial (129 to 116 kyr ago), a period with warmer global temperatures and higher sea level than today. We identify the orbital and freshwater forcings that could cause ice loss and probe the mechanisms that lead to warmer climate conditions.
Colin G. Jones, Fanny Adloff, Ben B. B. Booth, Peter M. Cox, Veronika Eyring, Pierre Friedlingstein, Katja Frieler, Helene T. Hewitt, Hazel A. Jeffery, Sylvie Joussaume, Torben Koenigk, Bryan N. Lawrence, Eleanor O'Rourke, Malcolm J. Roberts, Benjamin M. Sanderson, Roland Séférian, Samuel Somot, Pier Luigi Vidale, Detlef van Vuuren, Mario Acosta, Mats Bentsen, Raffaele Bernardello, Richard Betts, Ed Blockley, Julien Boé, Tom Bracegirdle, Pascale Braconnot, Victor Brovkin, Carlo Buontempo, Francisco Doblas-Reyes, Markus Donat, Italo Epicoco, Pete Falloon, Sandro Fiore, Thomas Frölicher, Neven S. Fučkar, Matthew J. Gidden, Helge F. Goessling, Rune Grand Graversen, Silvio Gualdi, José M. Gutiérrez, Tatiana Ilyina, Daniela Jacob, Chris D. Jones, Martin Juckes, Elizabeth Kendon, Erik Kjellström, Reto Knutti, Jason Lowe, Matthew Mizielinski, Paola Nassisi, Michael Obersteiner, Pierre Regnier, Romain Roehrig, David Salas y Mélia, Carl-Friedrich Schleussner, Michael Schulz, Enrico Scoccimarro, Laurent Terray, Hannes Thiemann, Richard A. Wood, Shuting Yang, and Sönke Zaehle
Earth Syst. Dynam., 15, 1319–1351, https://doi.org/10.5194/esd-15-1319-2024, https://doi.org/10.5194/esd-15-1319-2024, 2024
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We propose a number of priority areas for the international climate research community to address over the coming decade. Advances in these areas will both increase our understanding of past and future Earth system change, including the societal and environmental impacts of this change, and deliver significantly improved scientific support to international climate policy, such as future IPCC assessments and the UNFCCC Global Stocktake.
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
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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.
Jan De Rydt, Nicolas C. Jourdain, Yoshihiro Nakayama, Mathias van Caspel, Ralph Timmermann, Pierre Mathiot, Xylar S. Asay-Davis, Hélène Seroussi, Pierre Dutrieux, Ben Galton-Fenzi, David Holland, and Ronja Reese
Geosci. Model Dev., 17, 7105–7139, https://doi.org/10.5194/gmd-17-7105-2024, https://doi.org/10.5194/gmd-17-7105-2024, 2024
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Global climate models do not reliably simulate sea-level change due to ice-sheet–ocean interactions. We propose a community modelling effort to conduct a series of well-defined experiments to compare models with observations and study how models respond to a range of perturbations in climate and ice-sheet geometry. The second Marine Ice Sheet–Ocean Model Intercomparison Project will continue to lay the groundwork for including ice-sheet–ocean interactions in global-scale IPCC-class models.
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
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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.
Nicolaj Hansen, Andrew Orr, Xun Zou, Fredrik Boberg, Thomas J. Bracegirdle, Ella Gilbert, Peter L. Langen, Matthew A. Lazzara, Ruth Mottram, Tony Phillips, Ruth Price, Sebastian B. Simonsen, and Stuart Webster
The Cryosphere, 18, 2897–2916, https://doi.org/10.5194/tc-18-2897-2024, https://doi.org/10.5194/tc-18-2897-2024, 2024
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We investigated a melt event over the Ross Ice Shelf. We use regional climate models and a firn model to simulate the melt and compare the results with satellite data. We find that the firn model aligned well with observed melt days in certain parts of the ice shelf. The firn model had challenges accurately simulating the melt extent in the western sector. We identified potential reasons for these discrepancies, pointing to limitations in the models related to representing the cloud properties.
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
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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.
Ian Joughin, Daniel Shapero, and Pierre Dutrieux
The Cryosphere, 18, 2583–2601, https://doi.org/10.5194/tc-18-2583-2024, https://doi.org/10.5194/tc-18-2583-2024, 2024
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The Pine Island and Thwaites glaciers are losing ice to the ocean rapidly as warmer water melts their floating ice shelves. Models help determine how much such glaciers will contribute to sea level. We find that ice loss varies in response to how much melting the ice shelves are subjected to. Our estimated losses are also sensitive to how much the friction beneath the glaciers is reduced as it goes afloat. Melt-forced sea level rise from these glaciers is likely to be less than 10 cm by 2300.
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
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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.
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
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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.
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
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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.
Ryan L. Fogt, Quentin Dalaiden, and Gemma K. O'Connor
Clim. Past, 20, 53–76, https://doi.org/10.5194/cp-20-53-2024, https://doi.org/10.5194/cp-20-53-2024, 2024
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Antarctic sea ice is rapidly changing, with record lows set in 2017, 2022, and 2023 following decades of increase. To place these changes in a longer historical context, reconstructions have been created; however, they are quite different prior to observations. Here we find that the differences are more strongly tied to the implied connection of each reconstruction with the atmospheric circulation rather than differences in seasonality or geographic representation.
Gemma K. O'Connor, Paul R. Holland, Eric J. Steig, Pierre Dutrieux, and Gregory J. Hakim
The Cryosphere, 17, 4399–4420, https://doi.org/10.5194/tc-17-4399-2023, https://doi.org/10.5194/tc-17-4399-2023, 2023
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Glaciers in West Antarctica are rapidly melting, but the causes are unknown due to limited observations. A leading hypothesis is that an unusually large wind event in the 1940s initiated the ocean-driven melting. Using proxy reconstructions (e.g., using ice cores) and climate model simulations, we find that wind events similar to the 1940s event are relatively common on millennial timescales, implying that ocean variability or climate trends are also necessary to explain the start of ice loss.
Ronja Reese, Julius Garbe, Emily A. Hill, Benoît Urruty, Kaitlin A. Naughten, Olivier Gagliardini, Gaël Durand, Fabien Gillet-Chaulet, G. Hilmar Gudmundsson, David Chandler, Petra M. Langebroek, and Ricarda Winkelmann
The Cryosphere, 17, 3761–3783, https://doi.org/10.5194/tc-17-3761-2023, https://doi.org/10.5194/tc-17-3761-2023, 2023
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We use an ice sheet model to test where current climate conditions in Antarctica might lead. We find that present-day ocean and atmosphere conditions might commit an irreversible collapse of parts of West Antarctica which evolves over centuries to millennia. Importantly, this collapse is not irreversible yet.
Rajashree Tri Datta, Adam Herrington, Jan T. M. Lenaerts, David P. Schneider, Luke Trusel, Ziqi Yin, and Devon Dunmire
The Cryosphere, 17, 3847–3866, https://doi.org/10.5194/tc-17-3847-2023, https://doi.org/10.5194/tc-17-3847-2023, 2023
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Precipitation over Antarctica is one of the greatest sources of uncertainty in sea level rise estimates. Earth system models (ESMs) are a valuable tool for these estimates but typically run at coarse spatial resolutions. Here, we present an evaluation of the variable-resolution CESM2 (VR-CESM2) for the first time with a grid designed for enhanced spatial resolution over Antarctica to achieve the high resolution of regional climate models while preserving the two-way interactions of ESMs.
Erwin Lambert, André Jüling, Roderik S. W. van de Wal, and Paul R. Holland
The Cryosphere, 17, 3203–3228, https://doi.org/10.5194/tc-17-3203-2023, https://doi.org/10.5194/tc-17-3203-2023, 2023
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A major uncertainty in the study of sea level rise is the melting of the Antarctic ice sheet by the ocean. Here, we have developed a new model, named LADDIE, that simulates this ocean-driven melting of the floating parts of the Antarctic ice sheet. This model simulates fine-scale patterns of melting and freezing and requires significantly fewer computational resources than state-of-the-art ocean models. LADDIE can be used as a new tool to force high-resolution ice sheet models.
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
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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.
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
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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 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
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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.
Bertie W. J. Miles, Chris R. Stokes, Adrian Jenkins, Jim R. Jordan, Stewart S. R. Jamieson, and G. Hilmar Gudmundsson
The Cryosphere, 17, 445–456, https://doi.org/10.5194/tc-17-445-2023, https://doi.org/10.5194/tc-17-445-2023, 2023
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Satellite observations have shown that the Shirase Glacier catchment in East Antarctica has been gaining mass over the past 2 decades, a trend largely attributed to increased snowfall. Our multi-decadal observations of Shirase Glacier show that ocean forcing has also contributed to some of this recent mass gain. This has been caused by strengthening easterly winds reducing the inflow of warm water underneath the Shirase ice tongue, causing the glacier to slow down and thicken.
Lindsey Davidge, Eric J. Steig, and Andrew J. Schauer
Atmos. Meas. Tech., 15, 7337–7351, https://doi.org/10.5194/amt-15-7337-2022, https://doi.org/10.5194/amt-15-7337-2022, 2022
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We describe a continuous-flow analysis (CFA) method to measure Δ17O by laser spectroscopy, and we show that centimeter-scale information can be measured reliably in ice cores by this method. We present seasonally resolved Δ17O data from Greenland and demonstrate that the measurement precision is not reduced by the CFA process. Our results encourage the development and use of CFA methods for Δ17O, and they identify calibration strategies as a target for method improvement.
Clara Burgard, Nicolas C. Jourdain, Ronja Reese, Adrian Jenkins, and Pierre Mathiot
The Cryosphere, 16, 4931–4975, https://doi.org/10.5194/tc-16-4931-2022, https://doi.org/10.5194/tc-16-4931-2022, 2022
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The ocean-induced melt at the base of the floating ice shelves around Antarctica is one of the largest uncertainty factors in the Antarctic contribution to future sea-level rise. We assess the performance of several existing parameterisations in simulating basal melt rates on a circum-Antarctic scale, using an ocean simulation resolving the cavities below the shelves as our reference. We find that the simple quadratic slope-independent and plume parameterisations yield the best compromise.
Thomas Caton Harrison, Stavroula Biri, Thomas J. Bracegirdle, John C. King, Elizabeth C. Kent, Étienne Vignon, and John Turner
Weather Clim. Dynam., 3, 1415–1437, https://doi.org/10.5194/wcd-3-1415-2022, https://doi.org/10.5194/wcd-3-1415-2022, 2022
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Easterly winds encircle Antarctica, impacting sea ice and helping drive ocean currents which shield ice shelves from warmer waters. Reanalysis datasets give us our most complete picture of how these winds behave. In this paper we use satellite data, surface measurements and weather balloons to test how realistic recent reanalysis estimates are. The winds are generally accurate, especially in the most recent of the datasets, but important short-term variations are often misrepresented.
Antony Siahaan, Robin S. Smith, Paul R. Holland, Adrian Jenkins, Jonathan M. Gregory, Victoria Lee, Pierre Mathiot, Antony J. Payne, Jeff K. Ridley, and Colin G. Jones
The Cryosphere, 16, 4053–4086, https://doi.org/10.5194/tc-16-4053-2022, https://doi.org/10.5194/tc-16-4053-2022, 2022
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The UK Earth System Model is the first to fully include interactions of the atmosphere and ocean with the Antarctic Ice Sheet. Under the low-greenhouse-gas SSP1–1.9 (Shared Socioeconomic Pathway) scenario, the ice sheet remains stable over the 21st century. Under the strong-greenhouse-gas SSP5–8.5 scenario, the model predicts strong increases in melting of large ice shelves and snow accumulation on the surface. The dominance of accumulation leads to a sea level fall at the end of the century.
Bradley R. Markle and Eric J. Steig
Clim. Past, 18, 1321–1368, https://doi.org/10.5194/cp-18-1321-2022, https://doi.org/10.5194/cp-18-1321-2022, 2022
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The geochemistry preserved in polar ice can provide detailed histories of Earth’s climate over millennia. Here we use the stable isotope ratios of ice from many Antarctic ice cores to reconstruct temperature variability of Antarctica and the midlatitude Southern Hemisphere over tens of thousands of years. We improve upon existing methods to estimate temperature from the geochemical measurements and investigate the patterns of climate change in the past.
Ole Richter, David E. Gwyther, Benjamin K. Galton-Fenzi, and Kaitlin A. Naughten
Geosci. Model Dev., 15, 617–647, https://doi.org/10.5194/gmd-15-617-2022, https://doi.org/10.5194/gmd-15-617-2022, 2022
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Here we present an improved model of the Antarctic continental shelf ocean and demonstrate that it is capable of reproducing present-day conditions. The improvements are fundamental and regard the inclusion of tides and ocean eddies. We conclude that the model is well suited to gain new insights into processes that are important for Antarctic ice sheet retreat and global ocean changes. Hence, the model will ultimately help to improve projections of sea level rise and climate change.
Cited articles
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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.
The Antarctic Ice Sheet is losing ice, causing sea-level rise. However, it is not known whether...
