Articles | Volume 19, issue 1
https://doi.org/10.5194/tc-19-303-2025
© Author(s) 2025. 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-19-303-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Jan 2025
Research article |
| 24 Jan 2025
| 24 Jan 2025
Assessing the suitability of sites near Pine Island Glacier for subglacial bedrock drilling aimed at detecting Holocene retreat–readvance
British Antarctic Survey, Cambridge, CB3 0ET, UK
John Woodward
Department of Geography and Environmental Sciences, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, UK
Ian Nesbitt
School of Earth and Climate Sciences and the Climate Change Institute, University of Maine, Orono, ME 04469, USA
Kate Winter
Department of Geography and Environmental Sciences, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, UK
Seth Campbell
School of Earth and Climate Sciences and the Climate Change Institute, University of Maine, Orono, ME 04469, USA
Keir A. Nichols
Department of Earth Science and Engineering, Imperial College London, London, SW7 2AZ, UK
Ryan A. Venturelli
Department of Geology and Geological Engineering, Colorado School of Mines, Golden, CO 80401, USA
Scott Braddock
School of Earth and Climate Sciences and the Climate Change Institute, University of Maine, Orono, ME 04469, USA
Brent M. Goehring
Los Alamos National Laboratory, Los Alamos, NM 87545, USA
Brenda Hall
School of Earth and Climate Sciences and the Climate Change Institute, University of Maine, Orono, ME 04469, USA
Dylan H. Rood
Department of Earth Science and Engineering, Imperial College London, London, SW7 2AZ, UK
Greg Balco
Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94551, USA
Berkeley Geochronology Center, Berkeley, CA 94709, USA
Related authors
Jonathan R. Adams, Dylan H. Rood, Klaus Wilcken, Stephen J. Roberts, and Joanne S. Johnson
Geochronology Discuss., https://doi.org/10.5194/gchron-2024-34, https://doi.org/10.5194/gchron-2024-34, 2024
Preprint under review for GChron
Short summary
Short summary
Ice sheet mass loss is adding to sea-level rise, and is expected to increase, but by how much and how fast remains uncertain. Isotopes produced in rock at the Earth’s surface provide records of past ice sheet thinning which help predict future change but are more effective if they are precise enough to determine past changes to the nearest thousand years. The precision of carbon-14, an isotope which is guaranteed to record past change since the last ice age, can be improved.
Greg Balco, Nathan Brown, Keir Nichols, Ryan A. Venturelli, Jonathan Adams, Scott Braddock, Seth Campbell, Brent Goehring, Joanne S. Johnson, Dylan H. Rood, Klaus Wilcken, Brenda Hall, and John Woodward
The Cryosphere, 17, 1787–1801, https://doi.org/10.5194/tc-17-1787-2023, https://doi.org/10.5194/tc-17-1787-2023, 2023
Short summary
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Samples of bedrock recovered from below the West Antarctic Ice Sheet show that part of the ice sheet was thinner several thousand years ago than it is now and subsequently thickened. This is important because of concern that present ice thinning in this region may lead to rapid, irreversible sea level rise. The past episode of thinning at this site that took place in a similar, although not identical, climate was not irreversible; however, reversal required at least 3000 years to complete.
Jonathan R. Adams, Joanne S. Johnson, Stephen J. Roberts, Philippa J. Mason, Keir A. Nichols, Ryan A. Venturelli, Klaus Wilcken, Greg Balco, Brent Goehring, Brenda Hall, John Woodward, and Dylan H. Rood
The Cryosphere, 16, 4887–4905, https://doi.org/10.5194/tc-16-4887-2022, https://doi.org/10.5194/tc-16-4887-2022, 2022
Short summary
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Glaciers in West Antarctica are experiencing significant ice loss. Geological data provide historical context for ongoing ice loss in West Antarctica, including constraints on likely future ice sheet behaviour in response to climatic warming. We present evidence from rare isotopes measured in rocks collected from an outcrop next to Pope Glacier. These data suggest that Pope Glacier thinned faster and sooner after the last ice age than previously thought.
Joanne S. Johnson, Ryan A. Venturelli, Greg Balco, Claire S. Allen, Scott Braddock, Seth Campbell, Brent M. Goehring, Brenda L. Hall, Peter D. Neff, Keir A. Nichols, Dylan H. Rood, Elizabeth R. Thomas, and John Woodward
The Cryosphere, 16, 1543–1562, https://doi.org/10.5194/tc-16-1543-2022, https://doi.org/10.5194/tc-16-1543-2022, 2022
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Recent studies have suggested that some portions of the Antarctic Ice Sheet were less extensive than present in the last few thousand years. We discuss how past ice loss and regrowth during this time would leave its mark on geological and glaciological records and suggest ways in which future studies could detect such changes. Determining timing of ice loss and gain around Antarctica and conditions under which they occurred is critical for preparing for future climate-warming-induced changes.
Keir A. Nichols, Brent M. Goehring, Greg Balco, Joanne S. Johnson, Andrew S. Hein, and Claire Todd
The Cryosphere, 13, 2935–2951, https://doi.org/10.5194/tc-13-2935-2019, https://doi.org/10.5194/tc-13-2935-2019, 2019
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We studied the history of ice masses at three locations in the Weddell Sea Embayment, Antarctica. We measured rare isotopes in material sourced from mountains overlooking the Slessor Glacier, Foundation Ice Stream, and smaller glaciers on the Lassiter Coast. We show that ice masses were between 385 and 800 m thicker during the last glacial cycle than they are at present. The ice masses were both hundreds of metres thicker and remained thicker closer to the present than was previously thought.
Anna Ruth W. Halberstadt and Greg Balco
EGUsphere, https://doi.org/10.5194/egusphere-2025-2008, https://doi.org/10.5194/egusphere-2025-2008, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
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We developed a new framework for testing how well computer models of the Antarctic ice sheet match geological measurements of past ice thinning. By using more data and higher-spatial-resolution modeling, we improve how well models capture complex regions. Our approach also makes it easier to include new data as they become available. We describe multiple metrics for comparing models and data. This can help scientists better understand how the ice sheet changed in the past.
Adam C. Hawkins, Brent M. Goehring, and Brian Menounos
Geochronology, 7, 157–172, https://doi.org/10.5194/gchron-7-157-2025, https://doi.org/10.5194/gchron-7-157-2025, 2025
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We use a method called cosmogenic nuclide dating on bedrock surfaces and moraine boulders to determine the relative length of time an alpine glacier was larger or smaller than its current extent over the past 15 000 years. We also discuss several important limitations to this method. This method gives information on the duration of past ice advances and is useful in areas without other materials that can be dated.
Marie Bergelin, Andrew Gorin, Greg Balco, and William Cassata
EGUsphere, https://doi.org/10.5194/egusphere-2025-928, https://doi.org/10.5194/egusphere-2025-928, 2025
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Helium gas accumulates over time in minerals, but loss can occur depending on temperature. If partially retained, its loss can potentially be used for determining past surface temperatures. This study uses a model that accounts for complex gas loss to analyze helium retention in two minerals commonly found on the surface of Antarctica. We find one of the minerals retains helium while the other loses nearly all of the gas within hundred years, making it unsuitable as a climate reconstruction.
Greg Balco
EGUsphere, https://doi.org/10.5194/egusphere-2025-149, https://doi.org/10.5194/egusphere-2025-149, 2025
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This paper describes measurements of cosmogenic neon-21 concentrations in a widely distributed mineral standard material that is routinely used for quality control and interlaboratory comparison for measurements of other cosmic-ray-produced nuclides useful for various geochronology applications. Broadly, this facilitates improvement of precision and accuracy of these measurements and their applications in geochronology.
Gordon R. M. Bromley, Greg Balco, Margaret S. Jackson, Allie Balter-Kennedy, and Holly Thomas
Clim. Past, 21, 145–160, https://doi.org/10.5194/cp-21-145-2025, https://doi.org/10.5194/cp-21-145-2025, 2025
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We constructed a geologic record of East Antarctic Ice Sheet thickness from deposits at Otway Massif to directly assess how Earth's largest ice sheet responds to warmer-than-present climate. Our record confirms the long-term dominance of a cold polar climate but lacks a clear ice sheet response to the mid-Pliocene Warm Period, a common analogue for the future. Instead, an absence of moraines from the late Miocene–early Pliocene suggests the ice sheet was less extensive than present at that time.
Jonathan R. Adams, Dylan H. Rood, Klaus Wilcken, Stephen J. Roberts, and Joanne S. Johnson
Geochronology Discuss., https://doi.org/10.5194/gchron-2024-34, https://doi.org/10.5194/gchron-2024-34, 2024
Preprint under review for GChron
Short summary
Short summary
Ice sheet mass loss is adding to sea-level rise, and is expected to increase, but by how much and how fast remains uncertain. Isotopes produced in rock at the Earth’s surface provide records of past ice sheet thinning which help predict future change but are more effective if they are precise enough to determine past changes to the nearest thousand years. The precision of carbon-14, an isotope which is guaranteed to record past change since the last ice age, can be improved.
Joseph P. Tulenko, Greg Balco, Michael A. Clynne, and L. J. Patrick Muffler
Geochronology, 6, 639–652, https://doi.org/10.5194/gchron-6-639-2024, https://doi.org/10.5194/gchron-6-639-2024, 2024
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Cosmogenic nuclide exposure dating is an exceptional tool for reconstructing glacier histories, but reconstructions based on common target nuclides (e.g., 10Be) can be costly and time-consuming to generate. Here, we present a cost-effective proof-of-concept 21Ne exposure age chronology from Lassen Volcanic National Park, CA, USA, that broadly agrees with nearby 10Be chronologies but at lower precision.
Greg Balco, Andrew J. Conant, Dallas D. Reilly, Dallin Barton, Chelsea D. Willett, and Brett H. Isselhardt
Geochronology, 6, 571–584, https://doi.org/10.5194/gchron-6-571-2024, https://doi.org/10.5194/gchron-6-571-2024, 2024
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This paper describes how krypton isotopes produced by nuclear fission can be used to determine the age of microscopic particles of used nuclear fuel. This is potentially useful for international safeguard applications aimed at tracking and identifying nuclear materials, as well as geoscience applications involving dating post-1950s sediments or understanding environmental transport of nuclear materials.
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
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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.
Nicolas Bakken-French, Stephen J. Boyer, B. Clay Southworth, Megan Thayne, Dylan H. Rood, and Anders E. Carlson
The Cryosphere, 18, 4517–4530, https://doi.org/10.5194/tc-18-4517-2024, https://doi.org/10.5194/tc-18-4517-2024, 2024
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Repeat photography, field mapping, and remote sensing find that glaciers on Mt. Hood, Oregon, have lost about 25 % of their area in the first 2 decades of the 21st century and 17 % of their area in the last 7–8 years. The 21st century recession rate is more than 3 times faster than the 20th century average and 1.9 times faster than the fastest period of retreat within the 20th century. This unprecedented retreat corresponds to regional summer warming of 1.7–1.8°C relative to the early 1900s.
Allie Balter-Kennedy, Joerg M. Schaefer, Greg Balco, Meredith A. Kelly, Michael R. Kaplan, Roseanne Schwartz, Bryan Oakley, Nicolás E. Young, Jean Hanley, and Arianna M. Varuolo-Clarke
Clim. Past, 20, 2167–2190, https://doi.org/10.5194/cp-20-2167-2024, https://doi.org/10.5194/cp-20-2167-2024, 2024
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We date sedimentary deposits showing that the southeastern Laurentide Ice Sheet was at or near its southernmost extent from ~ 26 000 to 21 000 years ago, when sea levels were at their lowest, with climate records indicating glacial conditions. Slow deglaciation began ~ 22 000 years ago, shown by a rise in modeled local summer temperatures, but significant deglaciation in the region did not begin until ~ 18 000 years ago, when atmospheric CO2 began to rise, marking the end of the last ice age.
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
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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.
Marie Bergelin, Greg Balco, Lee B. Corbett, and Paul R. Bierman
Geochronology, 6, 491–502, https://doi.org/10.5194/gchron-6-491-2024, https://doi.org/10.5194/gchron-6-491-2024, 2024
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Cosmogenic nuclides, such as 10Be, are rare isotopes produced in rocks when exposed at Earth's surface and are valuable for understanding surface processes and landscape evolution. However, 10Be is usually measured in quartz minerals. Here we present advances in efficiently extracting and measuring 10Be in the pyroxene mineral. These measurements expand the use of 10Be as a dating tool for new rock types and provide opportunities to understand landscape processes in areas that lack quartz.
Greg Balco, Alan J. Hidy, William T. Struble, and Joshua J. Roering
Geochronology, 6, 71–76, https://doi.org/10.5194/gchron-6-71-2024, https://doi.org/10.5194/gchron-6-71-2024, 2024
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We describe a new method of reconstructing the long-term, pre-observational frequency and/or intensity of wildfires in forested landscapes using trace concentrations of the noble gases helium and neon that are formed in soil mineral grains by cosmic-ray bombardment of the Earth's surface.
Andrew G. Jones, Shaun A. Marcott, Andrew L. Gorin, Tori M. Kennedy, Jeremy D. Shakun, Brent M. Goehring, Brian Menounos, Douglas H. Clark, Matias Romero, and Marc W. Caffee
The Cryosphere, 17, 5459–5475, https://doi.org/10.5194/tc-17-5459-2023, https://doi.org/10.5194/tc-17-5459-2023, 2023
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Mountain glaciers today are fractions of their sizes 140 years ago, but how do these sizes compare to the past 11,000 years? We find that four glaciers in the United States and Canada have reversed a long-term trend of growth and retreated to positions last occupied thousands of years ago. Notably, each glacier occupies a unique position relative to its long-term history. We hypothesize that unequal modern retreat has caused the glaciers to be out of sync relative to their Holocene histories.
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
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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.
Adam C. Hawkins, Brian Menounos, Brent M. Goehring, Gerald Osborn, Ben M. Pelto, Christopher M. Darvill, and Joerg M. Schaefer
The Cryosphere, 17, 4381–4397, https://doi.org/10.5194/tc-17-4381-2023, https://doi.org/10.5194/tc-17-4381-2023, 2023
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Our study developed a record of glacier and climate change in the Mackenzie and Selwyn mountains of northwestern Canada over the past several hundred years. We estimate temperature change in this region using several methods and incorporate our glacier record with models of climate change to estimate how glacier volume in our study area has changed over time. Models of future glacier change show that our study area will become largely ice-free by the end of the 21st century.
Ling Fang, Theo M. Jenk, Dominic Winski, Karl Kreutz, Hanna L. Brooks, Emma Erwin, Erich Osterberg, Seth Campbell, Cameron Wake, and Margit Schwikowski
The Cryosphere, 17, 4007–4020, https://doi.org/10.5194/tc-17-4007-2023, https://doi.org/10.5194/tc-17-4007-2023, 2023
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Understanding the behavior of ocean–atmosphere teleconnections in the North Pacific during warm intervals can aid in predicting future warming scenarios. However, majority ice core records from Alaska–Yukon region only provide data for the last few centuries. This study introduces a continuous chronology for Denali ice core from Begguya, Alaska, using multiple dating methods. The early-Holocene-origin Denali ice core will facilitate future investigations of hydroclimate in the North Pacific.
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
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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.
Allie Balter-Kennedy, Joerg M. Schaefer, Roseanne Schwartz, Jennifer L. Lamp, Laura Penrose, Jennifer Middleton, Jean Hanley, Bouchaïb Tibari, Pierre-Henri Blard, Gisela Winckler, Alan J. Hidy, and Greg Balco
Geochronology, 5, 301–321, https://doi.org/10.5194/gchron-5-301-2023, https://doi.org/10.5194/gchron-5-301-2023, 2023
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Cosmogenic nuclides like 10Be are rare isotopes created in rocks exposed at the Earth’s surface and can be used to understand glacier histories and landscape evolution. 10Be is usually measured in the mineral quartz. Here, we show that 10Be can be reliably measured in the mineral pyroxene. We use the measurements to determine exposure ages and understand landscape processes in rocks from Antarctica that do not have quartz, expanding the use of this method to new rock types.
Jennifer R. Shadrick, Dylan H. Rood, Martin D. Hurst, Matthew D. Piggott, Klaus M. Wilcken, and Alexander J. Seal
Earth Surf. Dynam., 11, 429–450, https://doi.org/10.5194/esurf-11-429-2023, https://doi.org/10.5194/esurf-11-429-2023, 2023
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This study uses a coastal evolution model to interpret cosmogenic beryllium-10 concentrations and topographic data and, in turn, quantify long-term cliff retreat rates for four chalk sites on the south coast of England. By using a process-based model, clear distinctions between intertidal weathering rates have been recognised between chalk and sandstone rock coast sites, advocating the use of process-based models to interpret the long-term behaviour of rock coasts.
Greg Balco, Nathan Brown, Keir Nichols, Ryan A. Venturelli, Jonathan Adams, Scott Braddock, Seth Campbell, Brent Goehring, Joanne S. Johnson, Dylan H. Rood, Klaus Wilcken, Brenda Hall, and John Woodward
The Cryosphere, 17, 1787–1801, https://doi.org/10.5194/tc-17-1787-2023, https://doi.org/10.5194/tc-17-1787-2023, 2023
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Samples of bedrock recovered from below the West Antarctic Ice Sheet show that part of the ice sheet was thinner several thousand years ago than it is now and subsequently thickened. This is important because of concern that present ice thinning in this region may lead to rapid, irreversible sea level rise. The past episode of thinning at this site that took place in a similar, although not identical, climate was not irreversible; however, reversal required at least 3000 years to complete.
Anna Ruth W. Halberstadt, Greg Balco, Hannah Buchband, and Perry Spector
The Cryosphere, 17, 1623–1643, https://doi.org/10.5194/tc-17-1623-2023, https://doi.org/10.5194/tc-17-1623-2023, 2023
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This paper explores the use of multimillion-year exposure ages from Antarctic bedrock outcrops to benchmark ice sheet model predictions and thereby infer ice sheet sensitivity to warm climates. We describe a new approach for model–data comparison, highlight an example where observational data are used to distinguish end-member models, and provide guidance for targeted sampling around Antarctica that can improve understanding of ice sheet response to climate warming in the past and future.
Jonathan R. Adams, Joanne S. Johnson, Stephen J. Roberts, Philippa J. Mason, Keir A. Nichols, Ryan A. Venturelli, Klaus Wilcken, Greg Balco, Brent Goehring, Brenda Hall, John Woodward, and Dylan H. Rood
The Cryosphere, 16, 4887–4905, https://doi.org/10.5194/tc-16-4887-2022, https://doi.org/10.5194/tc-16-4887-2022, 2022
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Glaciers in West Antarctica are experiencing significant ice loss. Geological data provide historical context for ongoing ice loss in West Antarctica, including constraints on likely future ice sheet behaviour in response to climatic warming. We present evidence from rare isotopes measured in rocks collected from an outcrop next to Pope Glacier. These data suggest that Pope Glacier thinned faster and sooner after the last ice age than previously thought.
Natacha Gribenski, Marissa M. Tremblay, Pierre G. Valla, Greg Balco, Benny Guralnik, and David L. Shuster
Geochronology, 4, 641–663, https://doi.org/10.5194/gchron-4-641-2022, https://doi.org/10.5194/gchron-4-641-2022, 2022
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We apply quartz 3He paleothermometry along two deglaciation profiles in the European Alps to reconstruct temperature evolution since the Last Glacial Maximum. We observe a 3He thermal signal clearly colder than today in all bedrock surface samples exposed prior the Holocene. Current uncertainties in 3He diffusion kinetics do not permit distinguishing if this signal results from Late Pleistocene ambient temperature changes or from recent ground temperature variation due to permafrost degradation.
Ingalise Kindstedt, Kristin M. Schild, Dominic Winski, Karl Kreutz, Luke Copland, Seth Campbell, and Erin McConnell
The Cryosphere, 16, 3051–3070, https://doi.org/10.5194/tc-16-3051-2022, https://doi.org/10.5194/tc-16-3051-2022, 2022
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We show that neither the large spatial footprint of the MODIS sensor nor poorly constrained snow emissivity values explain the observed cold offset in MODIS land surface temperatures (LSTs) in the St. Elias. Instead, the offset is most prominent under conditions associated with near-surface temperature inversions. This work represents an advance in the application of MODIS LSTs to glaciated alpine regions, where we often depend solely on remote sensing products for temperature information.
Marie Bergelin, Jaakko Putkonen, Greg Balco, Daniel Morgan, Lee B. Corbett, and Paul R. Bierman
The Cryosphere, 16, 2793–2817, https://doi.org/10.5194/tc-16-2793-2022, https://doi.org/10.5194/tc-16-2793-2022, 2022
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Glacier ice contains information on past climate and can help us understand how the world changes through time. We have found and sampled a buried ice mass in Antarctica that is much older than most ice on Earth and difficult to date. Therefore, we developed a new dating application which showed the ice to be 3 million years old. Our new dating solution will potentially help to date other ancient ice masses since such old glacial ice could yield data on past environmental conditions on Earth.
Mae Kate Campbell, Paul R. Bierman, Amanda H. Schmidt, Rita Sibello Hernández, Alejandro García-Moya, Lee B. Corbett, Alan J. Hidy, Héctor Cartas Águila, Aniel Guillén Arruebarrena, Greg Balco, David Dethier, and Marc Caffee
Geochronology, 4, 435–453, https://doi.org/10.5194/gchron-4-435-2022, https://doi.org/10.5194/gchron-4-435-2022, 2022
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We used cosmogenic radionuclides in detrital river sediment to measure erosion rates of watersheds in central Cuba; erosion rates are lower than rock dissolution rates in lowland watersheds. Data from two different cosmogenic nuclides suggest that some basins may have a mixed layer deeper than is typically modeled and could have experienced significant burial after or during exposure. We conclude that significant mass loss may occur at depth through chemical weathering processes.
Klaus M. Wilcken, Alexandru T. Codilean, Réka-H. Fülöp, Steven Kotevski, Anna H. Rood, Dylan H. Rood, Alexander J. Seal, and Krista Simon
Geochronology, 4, 339–352, https://doi.org/10.5194/gchron-4-339-2022, https://doi.org/10.5194/gchron-4-339-2022, 2022
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Cosmogenic nuclides are now widely applied in the Earth sciences; however, more recent applications often push the analytical limits of the technique. Our study presents a comprehensive method for analysis of cosmogenic 10Be and 26Al samples down to isotope concentrations of a few thousand atoms per gram of sample, which opens the door to new and more varied applications of cosmogenic nuclide analysis.
Joanne S. Johnson, Ryan A. Venturelli, Greg Balco, Claire S. Allen, Scott Braddock, Seth Campbell, Brent M. Goehring, Brenda L. Hall, Peter D. Neff, Keir A. Nichols, Dylan H. Rood, Elizabeth R. Thomas, and John Woodward
The Cryosphere, 16, 1543–1562, https://doi.org/10.5194/tc-16-1543-2022, https://doi.org/10.5194/tc-16-1543-2022, 2022
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Recent studies have suggested that some portions of the Antarctic Ice Sheet were less extensive than present in the last few thousand years. We discuss how past ice loss and regrowth during this time would leave its mark on geological and glaciological records and suggest ways in which future studies could detect such changes. Determining timing of ice loss and gain around Antarctica and conditions under which they occurred is critical for preparing for future climate-warming-induced changes.
Jamey Stutz, Andrew Mackintosh, Kevin Norton, Ross Whitmore, Carlo Baroni, Stewart S. R. Jamieson, Richard S. Jones, Greg Balco, Maria Cristina Salvatore, Stefano Casale, Jae Il Lee, Yeong Bae Seong, Robert McKay, Lauren J. Vargo, Daniel Lowry, Perry Spector, Marcus Christl, Susan Ivy Ochs, Luigia Di Nicola, Maria Iarossi, Finlay Stuart, and Tom Woodruff
The Cryosphere, 15, 5447–5471, https://doi.org/10.5194/tc-15-5447-2021, https://doi.org/10.5194/tc-15-5447-2021, 2021
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Understanding the long-term behaviour of ice sheets is essential to projecting future changes due to climate change. In this study, we use rocks deposited along the margin of the David Glacier, one of the largest glacier systems in the world, to reveal a rapid thinning event initiated over 7000 years ago and endured for ~ 2000 years. Using physical models, we show that subglacial topography and ocean heat are important drivers for change along this sector of the Antarctic Ice Sheet.
Jennifer R. Shadrick, Martin D. Hurst, Matthew D. Piggott, Bethany G. Hebditch, Alexander J. Seal, Klaus M. Wilcken, and Dylan H. Rood
Earth Surf. Dynam., 9, 1505–1529, https://doi.org/10.5194/esurf-9-1505-2021, https://doi.org/10.5194/esurf-9-1505-2021, 2021
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Here we use topographic and 10Be concentration data to optimise a coastal evolution model. Cliff retreat rates are calculated for two UK sites for the past 8000 years and, for the first time, highlight a strong link between the rate of sea level rise and long-term cliff retreat rates. This method enables us to study past cliff response to sea level rise and so to greatly improve forecasts of future responses to accelerations in sea level rise that will result from climate change.
Trevor R. Hillebrand, John O. Stone, Michelle Koutnik, Courtney King, Howard Conway, Brenda Hall, Keir Nichols, Brent Goehring, and Mette K. Gillespie
The Cryosphere, 15, 3329–3354, https://doi.org/10.5194/tc-15-3329-2021, https://doi.org/10.5194/tc-15-3329-2021, 2021
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We present chronologies from Darwin and Hatherton glaciers to better constrain ice sheet retreat during the last deglaciation in the Ross Sector of Antarctica. We use a glacier flowband model and an ensemble of 3D ice sheet model simulations to show that (i) the whole glacier system likely thinned steadily from about 9–3 ka, and (ii) the grounding line likely reached the Darwin–Hatherton Glacier System at about 3 ka, which is ≥3.8 kyr later than was suggested by previous reconstructions.
Greg Balco, Benjamin D. DeJong, John C. Ridge, Paul R. Bierman, and Dylan H. Rood
Geochronology, 3, 1–33, https://doi.org/10.5194/gchron-3-1-2021, https://doi.org/10.5194/gchron-3-1-2021, 2021
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The North American Varve Chronology (NAVC) is a sequence of 5659 annual sedimentary layers that were deposited in proglacial lakes adjacent to the retreating Laurentide Ice Sheet ca. 12 500–18 200 years ago. We attempt to synchronize this record with Greenland ice core and other climate records that cover the same time period by detecting variations in global fallout of atmospherically produced beryllium-10 in NAVC sediments.
Kate Winter, Emily A. Hill, G. Hilmar Gudmundsson, and John Woodward
Earth Syst. Sci. Data, 12, 3453–3467, https://doi.org/10.5194/essd-12-3453-2020, https://doi.org/10.5194/essd-12-3453-2020, 2020
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Satellite measurements of the English Coast in the Antarctic Peninsula reveal that glaciers are thinning and losing mass, but ice thickness data are required to assess these changes, in terms of ice flux and sea level contribution. Our ice-penetrating radar measurements reveal that low-elevation subglacial channels control fast-flowing ice streams, which release over 39 Gt of ice per year to floating ice shelves. This topography could make ice flows susceptible to future instability.
Allie Balter-Kennedy, Gordon Bromley, Greg Balco, Holly Thomas, and Margaret S. Jackson
The Cryosphere, 14, 2647–2672, https://doi.org/10.5194/tc-14-2647-2020, https://doi.org/10.5194/tc-14-2647-2020, 2020
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We describe new geologic evidence from Antarctica that demonstrates changes in East Antarctic Ice Sheet (EAIS) extent over the past ~ 15 million years. Our data show that the EAIS was a persistent feature in the Transantarctic Mountains for much of that time, including some (but not all) times when global temperature may have been warmer than today. Overall, our results comprise a long-term record of EAIS change and may provide useful constraints for ice sheet models and sea-level estimates.
Greg Balco
Geochronology, 2, 169–175, https://doi.org/10.5194/gchron-2-169-2020, https://doi.org/10.5194/gchron-2-169-2020, 2020
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Geologic dating methods generally do not directly measure ages. Instead, interpreting a geochemical measurement as an age requires a middle layer of calculations and supporting data, and the fact that this layer continually improves is an obstacle to synoptic analysis of geochronological data. This paper describes a prototype data management and analysis system that addresses this obstacle by making the middle-layer calculations transparent and dynamic to the user.
Michal Ben-Israel, Ari Matmon, Alan J. Hidy, Yoav Avni, and Greg Balco
Earth Surf. Dynam., 8, 289–301, https://doi.org/10.5194/esurf-8-289-2020, https://doi.org/10.5194/esurf-8-289-2020, 2020
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Early-to-mid Miocene erosion rates were inferred using cosmogenic 21Ne measured in chert pebbles transported by the Miocene Hazeva River (~ 18 Ma). Miocene erosion rates are faster compared to Quaternary rates in the region. Faster Miocene erosion rates could be due to a response to topographic changes brought on by tectonic uplift, wetter climate in the region during the Miocene, or a combination of both.
Keir A. Nichols, Brent M. Goehring, Greg Balco, Joanne S. Johnson, Andrew S. Hein, and Claire Todd
The Cryosphere, 13, 2935–2951, https://doi.org/10.5194/tc-13-2935-2019, https://doi.org/10.5194/tc-13-2935-2019, 2019
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We studied the history of ice masses at three locations in the Weddell Sea Embayment, Antarctica. We measured rare isotopes in material sourced from mountains overlooking the Slessor Glacier, Foundation Ice Stream, and smaller glaciers on the Lassiter Coast. We show that ice masses were between 385 and 800 m thicker during the last glacial cycle than they are at present. The ice masses were both hundreds of metres thicker and remained thicker closer to the present than was previously thought.
Keir A. Nichols and Brent M. Goehring
Geochronology, 1, 43–52, https://doi.org/10.5194/gchron-1-43-2019, https://doi.org/10.5194/gchron-1-43-2019, 2019
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We describe observations of anomalously high measurements of C-14 made from geologic material. We undertake a systematic investigation to identify the source of contamination, which we hypothesise is sourced from a commonly used method that is used prior to sample analysis. We find that the method does introduce modern carbon to samples and elevates C-14 measurements. We describe a standard procedure that effectively removes contamination from the aforementioned method.
Greg Balco, Kimberly Blisniuk, and Alan Hidy
Geochronology, 1, 1–16, https://doi.org/10.5194/gchron-1-1-2019, https://doi.org/10.5194/gchron-1-1-2019, 2019
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This article applies a new geochemical dating method to determine the age of sedimentary deposits useful in reconstructing slip rates on a major fault system.
Stephanie L. Strother, Ulrich Salzmann, Francesca Sangiorgi, Peter K. Bijl, Jörg Pross, Carlota Escutia, Ariadna Salabarnada, Matthew J. Pound, Jochen Voss, and John Woodward
Biogeosciences, 14, 2089–2100, https://doi.org/10.5194/bg-14-2089-2017, https://doi.org/10.5194/bg-14-2089-2017, 2017
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One of the main challenges in Antarctic vegetation reconstructions is the uncertainty in unambiguously identifying reworked pollen and spore assemblages in marine sedimentary records influenced by waxing and waning ice sheets. This study uses red fluorescence and digital imaging as a new tool to identify reworking in a marine sediment core from circum-Antarctic waters to reconstruct Cenozoic climate change and vegetation with high confidence.
Martin D. Hurst, Dylan H. Rood, and Michael A. Ellis
Earth Surf. Dynam., 5, 67–84, https://doi.org/10.5194/esurf-5-67-2017, https://doi.org/10.5194/esurf-5-67-2017, 2017
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Beryllium-10 is a rare isotope that only forms near to the Earth surface, allowing rock surfaces to be dated. In this paper we develop a numerical model for the evolution of shore platforms and associated 10Be concentrations to explore the potential for this method to reveal long-term rates of sea cliff retreat. Tides, sea level, cliffs and beaches all modify how rapidly 10Be accumulates on the shore platform, but there is great potential to measure rates of cliff retreat and platform erosion.
Amanda H. Schmidt, Thomas B. Neilson, Paul R. Bierman, Dylan H. Rood, William B. Ouimet, and Veronica Sosa Gonzalez
Earth Surf. Dynam., 4, 819–830, https://doi.org/10.5194/esurf-4-819-2016, https://doi.org/10.5194/esurf-4-819-2016, 2016
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In order to test the assumption that erosion rates derived from Be-10 are not affected by increases in erosion due to contemporary agricultural land use, we measured erosion rates in three tributaries of the Mekong River. We find that in the most heavily agricultural landscapes, the apparent long-term erosion rate correlates best with measures of modern land use, suggesting that agriculture has eroded below the mixed layer and is affecting apparent erosion rates derived from Be-10.
Tom Watts, Nick Rutter, Peter Toose, Chris Derksen, Melody Sandells, and John Woodward
The Cryosphere, 10, 2069–2074, https://doi.org/10.5194/tc-10-2069-2016, https://doi.org/10.5194/tc-10-2069-2016, 2016
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Ice layers in snowpacks introduce uncertainty in satellite-derived estimates of snow water equivalent, have ecological impacts on plants and animals, and change the thermal and vapour transport properties of the snowpack. Here we present a new field method for measuring the density of ice layers. The method was used in the Arctic and mid-latitudes; the mean measured ice layer density was significantly higher than values typically used in the literature.
Matthew J. Westoby, Stuart A. Dunning, John Woodward, Andrew S. Hein, Shasta M. Marrero, Kate Winter, and David E. Sugden
Earth Surf. Dynam., 4, 515–529, https://doi.org/10.5194/esurf-4-515-2016, https://doi.org/10.5194/esurf-4-515-2016, 2016
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We quantify the surface evolution of an Antarctic blue-ice moraine complex over 1- and 12-month intervals using repeat terrestrial laser scanning and structure-from-motion photogrammetry. We find net uplift and lateral movement of moraines within a field season (mean uplift ~ 0.10 m) and local surface lowering of a similar magnitude. Net uplift across the site between seasons was 0.07 m. Such data offer new opportunities to understand linkages between surface ablation, ice flow and debris supply within moraines.
S. J. Livingstone, C. D. Clark, J. Woodward, and J. Kingslake
The Cryosphere, 7, 1721–1740, https://doi.org/10.5194/tc-7-1721-2013, https://doi.org/10.5194/tc-7-1721-2013, 2013
Related subject area
Discipline: Ice sheets | Subject: Antarctic
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
Modelling GNSS-observed seasonal velocity changes of the Ross Ice Shelf, Antarctica, using the Ice-sheet and Sea-level System Model (ISSM)
A fast and simplified subglacial hydrological model for the Antarctic Ice Sheet and outlet glaciers
Satellite data reveal details of glacial isostatic adjustment in the Amundsen Sea Embayment, West Antarctica
The impact of regional-scale upper mantle heterogeneity on glacial isostatic adjustment in West Antarctica
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
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
Review article: Feature tracing in radio-echo sounding products of terrestrial ice sheets and planetary bodies
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
Viscoelastic mechanics of tidally induced lake drainage in the Amery grounding zone
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
Insights into the vulnerability of Antarctic glaciers from the ISMIP6 ice sheet model ensemble and associated uncertainty
Oceanic gateways to Antarctic grounding lines – Impact of critical access depths on sub-shelf melt
Evaluation of four calving laws for Antarctic ice shelves
Englacial architecture of Lambert Glacier, East Antarctica
Mass changes of the northern Antarctic Peninsula Ice Sheet derived from repeat bi-static synthetic aperture radar acquisitions for the period 2013–2017
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
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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
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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
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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.
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
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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
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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
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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
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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
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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
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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
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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
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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.
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
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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.
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
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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.
Matthias O. Willen, Bert Wouters, Taco Broerse, Eric Buchta, and Veit Helm
EGUsphere, https://doi.org/10.5194/egusphere-2024-3086, https://doi.org/10.5194/egusphere-2024-3086, 2024
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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 GNSS measurements have been able to observe this bedrock motion. We have combined satellite data and quantified a region-wide bedrock motion that independently matches GNSS measurements. This can improve ice-sheet predictions.
Erica Margaret Lucas, Natalya Gomez, and Terry Wilson
EGUsphere, https://doi.org/10.5194/egusphere-2024-2957, https://doi.org/10.5194/egusphere-2024-2957, 2024
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We investigate the effects of incorporating regional-scale lateral variability (~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 ~25–125 years) and projected (next ~300 years) ice mass changes, especially in coastal regions that undergo rapid ice mass loss.
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
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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
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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.
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
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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
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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.
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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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.
Hameed Moqadam and Olaf Eisen
EGUsphere, https://doi.org/10.5194/egusphere-2024-1674, https://doi.org/10.5194/egusphere-2024-1674, 2024
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This is an overview on 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 two decades. Finally, we conclude by introducing the gaps and opportunities for further advancement in this field, and present possible future directions.
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
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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
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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
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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
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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
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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.
Hanwen Zhang, Richard F. Katz, and Laura A. Stevens
EGUsphere, https://doi.org/10.48550/arXiv.2311.01249, https://doi.org/10.48550/arXiv.2311.01249, 2024
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In Antarctica, supraglacial lakes are formed by melting near the grounding lines, where grounded ice sheets transition to floating ice shelves. We model the tidal flexure near the grounding lines and analyse its contribution to lake drainage through hydrofracturing. We show that tidal flexure and lake water pressure together control lake drainage in the Amery Ice Shelf, which indicates the importance of tidal stress to processes associated with hydrofracturing near the grounding lines.
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
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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
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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
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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
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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
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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
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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
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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.
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
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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.
Hélène Seroussi, Vincent Verjans, Sophie Nowicki, Antony J. Payne, Heiko Goelzer, William H. Lipscomb, Ayako Abe-Ouchi, Cécile Agosta, Torsten Albrecht, Xylar Asay-Davis, Alice Barthel, Reinhard Calov, Richard Cullather, Christophe Dumas, Benjamin K. Galton-Fenzi, Rupert Gladstone, Nicholas R. Golledge, Jonathan M. Gregory, Ralf Greve, Tore Hattermann, Matthew J. Hoffman, Angelika Humbert, Philippe Huybrechts, Nicolas C. Jourdain, Thomas Kleiner, Eric Larour, Gunter R. Leguy, Daniel P. Lowry, Chistopher M. Little, Mathieu Morlighem, Frank Pattyn, Tyler Pelle, Stephen F. Price, Aurélien Quiquet, Ronja Reese, Nicole-Jeanne Schlegel, Andrew Shepherd, Erika Simon, Robin S. Smith, Fiammetta Straneo, Sainan Sun, Luke D. Trusel, Jonas Van Breedam, Peter Van Katwyk, Roderik S. W. van de Wal, Ricarda Winkelmann, Chen Zhao, Tong Zhang, and Thomas Zwinger
The Cryosphere, 17, 5197–5217, https://doi.org/10.5194/tc-17-5197-2023, https://doi.org/10.5194/tc-17-5197-2023, 2023
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Mass loss from Antarctica is a key contributor to sea level rise over the 21st century, and the associated uncertainty dominates sea level projections. We highlight here the Antarctic glaciers showing the largest changes and quantify the main sources of uncertainty in their future evolution using an ensemble of ice flow models. We show that on top of Pine Island and Thwaites glaciers, Totten and Moscow University glaciers show rapid changes and a strong sensitivity to warmer ocean conditions.
Lena Nicola, Ronja Reese, Moritz Kreuzer, Torsten Albrecht, and Ricarda Winkelmann
EGUsphere, https://doi.org/10.5194/egusphere-2023-2583, https://doi.org/10.5194/egusphere-2023-2583, 2023
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We identify potential oceanic gateways to Antarctic grounding lines based on high-resolution bathymetry data and examine the effect of critical access depths on basal melt rates. These gateways manifest the deepest topographic features that connect the deeper open ocean and the ice-shelf cavity. We detect 'prominent' oceanic gateways in some Antarctic regions and estimate an upper limit of melt rate changes in case all warm water masses gain access to the cavities.
Joel A. Wilner, Mathieu Morlighem, and Gong Cheng
The Cryosphere, 17, 4889–4901, https://doi.org/10.5194/tc-17-4889-2023, https://doi.org/10.5194/tc-17-4889-2023, 2023
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We use numerical modeling to study iceberg calving off of ice shelves in Antarctica. We examine four widely used mathematical descriptions of calving (
calving laws), under the assumption that Antarctic ice shelf front positions should be in steady state under the current climate forcing. We quantify how well each of these calving laws replicates the observed front positions. Our results suggest that the eigencalving and von Mises laws are most suitable for Antarctic ice shelves.
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
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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.
Thorsten Seehaus, Christian Sommer, Thomas Dethinne, and Philipp Malz
The Cryosphere, 17, 4629–4644, https://doi.org/10.5194/tc-17-4629-2023, https://doi.org/10.5194/tc-17-4629-2023, 2023
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Existing mass budget estimates for the northern Antarctic Peninsula (>70° S) are affected by considerable limitations. We carried out the first region-wide analysis of geodetic mass balances throughout this region (coverage of 96.4 %) for the period 2013–2017 based on repeat pass bi-static TanDEM-X acquisitions. A total mass budget of −24.1±2.8 Gt/a is revealed. Imbalanced high ice discharge, particularly at former ice shelf tributaries, is the main driver of overall ice loss.
Cited articles
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.
Balco, G., Brown, N., Nichols, K., Venturelli, R. A., Adams, J., Braddock, S., Campbell, S., Goehring, B., Johnson, J. S., Rood, D. H., Wilcken, K., Hall, B., and Woodward, J.: Reversible ice sheet thinning in the Amundsen Sea Embayment during the Late Holocene, The Cryosphere, 17, 1787–1801, https://doi.org/10.5194/tc-17-1787-2023, 2023.
Balter-Kennedy, A., Schaefer, J. M., Briner, J. P., Young, N. E., Walcott, C., Kuhl, T., Moravec, E., Keisling, B. A., Anandakrishnan, S., Stevens, N., and Brown, N.: First Results from GreenDrill: Exposure dating in sub-ice material from Prudhoe Dome, northwestern Greenland, Abstract, AGU Fall Meeting, San Francisco, USA, 2023, https://agu.confex.com/agu/fm23/meetingapp.cgi/Paper/1314764 (last access: 13 January 2025), 2023a.
Balter-Kennedy, A., Schaefer, J. M., Schwartz, R., Lamp, J. L., Penrose, L., Middleton, J., Hanley, J., Tibari, B., Blard, P.-H., Winckler, G., Hidy, A. J., and Balco, G.: Cosmogenic 10Be in pyroxene: laboratory progress, production rate systematics, and application of the 10Be–3He nuclide pair in the Antarctic Dry Valleys, Geochronology, 5, 301–321, https://doi.org/10.5194/gchron-5-301-2023, 2023b.
Bergelin, M., Balco, G., Corbett, L. B., and Bierman, P. R.: Production rate calibration for cosmogenic 10Be in pyroxene by applying a rapid fusion method to 10Be-saturated samples from the Transantarctic Mountains, Antarctica, Geochronology, 6, 491–502, https://doi.org/10.5194/gchron-6-491-2024, 2024.
Bindschadler, R., Vornberger, P., Fleming, A. H., Fox, A. J., Mullins, J., Binnie, D., Paulsen, S. J., Granneman, B., and Gorodetzky, D.: The Landsat Image Mosaic of Antarctica, Remote Sens. Environ., 112, 4214–4226, 2008.
Boeckmann, G. V., Gibson, C. J., Kuhl, T. W., Moravec, E., Johnson, J. A., Meulemans, Z., and Slawny, K.: Adaptation of the Winkie Drill for subglacial bedrock sampling, Ann. Glaciol., 62, 109–117, https://doi.org/10.1017/aog.2020.73, 2021.
Braddock, S., Hall, B. L., Johnson, J. S., Balco, G., Spoth, M., Whitehouse, P. L., Campbell, S., Goehring, B. M., Rood, D. H., and Woodward, J.: Relative sea-level data preclude major late Holocene ice-mass change in Pine Island Bay, Nat. Geosci., 15, 568–572, 2022.
Braddock, S., Venturelli, R. A., Nichols, K. A., Moravec, E., Boeckmann, G. V., Campbell, S., Balco, G., Ackert, R., Small, D., Johnson, J. S., Dunbar, N., Woodward, J., Mukhopadhyay, S., and Goehring, B.: Lessons learned from shallow subglacial bedrock drilling campaigns in Antarctica, Ann. Glaciol., 65, e18, https://doi.org/10.1017/aog.2024.12, 2024.
Carracedo, A., Rodés, Á., Smellie, J. L., and Stuart, F. M.: Episodic erosion in West Antarctica inferred from cosmogenic 3He and 10Be in olivine from Mount Hampton, Geomorphology, 327, 438–445, https://doi.org/10.1016/j.geomorph.2018.11.019, 2019.
Briner, J. P., Walcott, C. K., Schaefer, J. M., Young, N. E., MacGregor, J. A., Poinar, K., Keisling, B. A., Anandakrishnan, S., Albert, M. R., Kuhl, T., and Boeckmann, G.: Drill-site selection for cosmogenic-nuclide exposure dating of the bed of the Greenland Ice Sheet, The Cryosphere, 16, 3933–3948, https://doi.org/10.5194/tc-16-3933-2022, 2022.
Daniels, D. J.: Ground Penetrating Radar, 2nd edn., The Institution of Engineering and Technology, London, UK, 752 pp., ISBN 9780863413605, 2004.
Howat, I., Porter, C., Noh, M. -J., Husby, E., Khuvis, S., Danish, E., Tomko, K., Gardiner, J., Negrete, A., Yadav, B., Klassen, J., Kelleher, C., Cloutier, M., Bakker, J., Enos, J., Arnold, G., Bauer, G., and Morin, P.: The Reference Elevation Model of Antarctica – Mosaics, Version 2, Harvard Dataverse [data set], https://doi.org/10.7910/DVN/EBW8UC, 2022.
Jeong, S., Howat, I. M., and Bassis, J. N.: Accelerated ice shelf rifting and retreat at Pine Island Glacier, West Antarctica, Geophys. Res. Lett., 43, 11720–11725, https://doi.org/10.1002/2016GL071360, 2016.
Johnson, J. S. and Smellie, J. L.: Zeolites compositions as proxies for eruptive palaeoenvironment, Geochem. Geophy. Geosy., 8, Q03009, https://doi.org/10.1029/2006GC001450, 2007.
Johnson, J. S., Bentley, M. J., and Gohl, K.: First exposure ages from the Amundsen Sea Embayment, West Antarctica: The Late Quaternary context for recent thinning of Pine Island, Smith, and Pope Glaciers, Geology, 36, 223–226, 2008.
Johnson, J. S., Bentley, M. J., Smith, J. A., Finkel, R. C., Rood, D. H., Gohl, K., Balco, G., Larter, R. D., and Schaefer, J. M.: Rapid thinning of Pine Island Glacier in the early Holocene, Science, 343, 999–1001, 2014.
Johnson, J. S., Nichols, K. A., Goehring, B. M., Balco, G., and Schaefer, J. M.: Abrupt mid-Holocene ice loss in the western Weddell Sea Embayment of Antarctica, Earth Planet. Sc. Lett., 518, 127–135, https://doi.org/10.1016/j.epsl.2019.05.002, 2019.
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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).
Determining where and when the Antarctic ice sheet was smaller than present requires recovery...
