Articles | Volume 17, issue 10
https://doi.org/10.5194/tc-17-4399-2023
© Author(s) 2023. 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-17-4399-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Characteristics and rarity of the strong 1940s westerly wind event over the Amundsen Sea, West Antarctica
Department of Earth and Space Sciences, University of Washington, Seattle, WA, USA
Paul R. Holland
British Antarctic Survey, Cambridge, UK
Eric J. Steig
Department of Earth and Space Sciences, University of Washington, Seattle, WA, USA
Department of Atmospheric Sciences, University of Washington, Seattle, WA, USA
Pierre Dutrieux
British Antarctic Survey, Cambridge, UK
Gregory J. Hakim
Department of Atmospheric Sciences, University of Washington, Seattle, WA, USA
Related authors
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
Short summary
Short summary
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.
Paul R. Holland, Gemma K. O'Connor, Thomas J. Bracegirdle, Pierre Dutrieux, Kaitlin A. Naughten, Eric J. Steig, David P. Schneider, Adrian Jenkins, and James A. Smith
The Cryosphere, 16, 5085–5105, https://doi.org/10.5194/tc-16-5085-2022, https://doi.org/10.5194/tc-16-5085-2022, 2022
Short summary
Short summary
The Antarctic Ice Sheet is losing ice, causing sea-level rise. However, it is not known whether human-induced climate change has contributed to this ice loss. In this study, we use evidence from climate models and palaeoclimate measurements (e.g. ice cores) to suggest that the ice loss was triggered by natural climate variations but is now sustained by human-forced climate change. This implies that future greenhouse-gas emissions may influence sea-level rise from Antarctica.
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
Short summary
Short summary
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.
David T. Bett, Alexander T. Bradley, C. Rosie Williams, Paul R. Holland, Robert J. Arthern, and Daniel N. Goldberg
The Cryosphere, 18, 2653–2675, https://doi.org/10.5194/tc-18-2653-2024, https://doi.org/10.5194/tc-18-2653-2024, 2024
Short summary
Short summary
A new ice–ocean model simulates future ice sheet evolution in the Amundsen Sea sector of Antarctica. Substantial ice retreat is simulated in all scenarios, with some retreat still occurring even with no future ocean melting. The future of small "pinning points" (islands of ice that contact the seabed) is an important control on this retreat. Ocean melting is crucial in causing these features to go afloat, providing the link by which climate change may affect this sector's sea level contribution.
Heather Louise Selley, Anna E. Hogg, Benjamin J. Davison, Pierre Dutrieux, and Thomas Slater
EGUsphere, https://doi.org/10.5194/egusphere-2024-1442, https://doi.org/10.5194/egusphere-2024-1442, 2024
Short summary
Short summary
We used satellite observations to measure recent changes in ice speed and flow direction in the Pope, Smith and Kohler Region of West Antarctica (2005–2022). We found substantial speed up on seven ice streams of up to 87 %. However, Kohler West Glacier has slowed by 10%, due to the redirection of ice flow into its rapidly thinning neighbour. This process of ‘ice piracy’ hasn’t previously been directly observed on this rapid timescale and may influence future ice shelf and sheet mass changes.
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
Short summary
Short summary
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.
Feng Zhu, Julien Emile-Geay, Gregory J. Hakim, Dominique Guillot, Deborah Khider, Robert Tardif, and Walter A. Perkins
Geosci. Model Dev., 17, 3409–3431, https://doi.org/10.5194/gmd-17-3409-2024, https://doi.org/10.5194/gmd-17-3409-2024, 2024
Short summary
Short summary
Climate field reconstruction encompasses methods that estimate the evolution of climate in space and time based on natural archives. It is useful to investigate climate variations and validate climate models, but its implementation and use can be difficult for non-experts. This paper introduces a user-friendly Python package called cfr to make these methods more accessible, thanks to the computational and visualization tools that facilitate efficient and reproducible research on past climates.
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 Discuss., https://doi.org/10.5194/cp-2024-19, https://doi.org/10.5194/cp-2024-19, 2024
Revised manuscript accepted for CP
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Caroline R. Holmes, Thomas J. Bracegirdle, Paul R. Holland, Julienne Stroeve, and Jeremy Wilkinson
EGUsphere, https://doi.org/10.5194/egusphere-2023-2881, https://doi.org/10.5194/egusphere-2023-2881, 2023
Short summary
Short summary
Until recently, observed Antarctic sea ice was increasing, while in contrast numerical climate models simulated a decrease over the same period (1979–2014). This apparent mismatch was one reason for low confidence in model projections of large 21st century sea ice loss and related aspects of Southern Hemisphere climate. Here we show that, with the inclusion of several low Antarctic sea ice years (notably 2017, 2022 and 2023), we can no longer conclude that modelled and observed trends differ.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Paul R. Holland, Gemma K. O'Connor, Thomas J. Bracegirdle, Pierre Dutrieux, Kaitlin A. Naughten, Eric J. Steig, David P. Schneider, Adrian Jenkins, and James A. Smith
The Cryosphere, 16, 5085–5105, https://doi.org/10.5194/tc-16-5085-2022, https://doi.org/10.5194/tc-16-5085-2022, 2022
Short summary
Short summary
The Antarctic Ice Sheet is losing ice, causing sea-level rise. However, it is not known whether human-induced climate change has contributed to this ice loss. In this study, we use evidence from climate models and palaeoclimate measurements (e.g. ice cores) to suggest that the ice loss was triggered by natural climate variations but is now sustained by human-forced climate change. This implies that future greenhouse-gas emissions may influence sea-level rise from Antarctica.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Xuewei Li, Qinghua Yang, Lejiang Yu, Paul R. Holland, Chao Min, Longjiang Mu, and Dake Chen
The Cryosphere Discuss., https://doi.org/10.5194/tc-2020-359, https://doi.org/10.5194/tc-2020-359, 2021
Preprint withdrawn
Short summary
Short summary
The Arctic sea ice thickness record minimum is confirmed occurring in autumn 2011. The dynamic and thermodynamic processes leading to the minimum thickness is analyzed based on a daily sea ice thickness reanalysis data covering the melting season. The results demonstrate that the dynamic transport of multiyear ice and the subsequent surface energy budget response is a critical mechanism actively contributing to the evolution of Arctic sea ice thickness in 2011.
Jenna A. Epifanio, Edward J. Brook, Christo Buizert, Jon S. Edwards, Todd A. Sowers, Emma C. Kahle, Jeffrey P. Severinghaus, Eric J. Steig, Dominic A. Winski, Erich C. Osterberg, Tyler J. Fudge, Murat Aydin, Ekaterina Hood, Michael Kalk, Karl J. Kreutz, David G. Ferris, and Joshua A. Kennedy
Clim. Past, 16, 2431–2444, https://doi.org/10.5194/cp-16-2431-2020, https://doi.org/10.5194/cp-16-2431-2020, 2020
Short summary
Short summary
A new ice core drilled at the South Pole provides a 54 000-year paleo-environmental record including the composition of the past atmosphere. This paper describes the gas chronology for the South Pole ice core, based on a high-resolution methane record. The new gas chronology, in combination with the existing ice age scale from Winski et al. (2019), allows a model-independent reconstruction of the delta age record.
Jessica A. Badgeley, Eric J. Steig, Gregory J. Hakim, and Tyler J. Fudge
Clim. Past, 16, 1325–1346, https://doi.org/10.5194/cp-16-1325-2020, https://doi.org/10.5194/cp-16-1325-2020, 2020
Tyler J. Fudge, David A. Lilien, Michelle Koutnik, Howard Conway, C. Max Stevens, Edwin D. Waddington, Eric J. Steig, Andrew J. Schauer, and Nicholas Holschuh
Clim. Past, 16, 819–832, https://doi.org/10.5194/cp-16-819-2020, https://doi.org/10.5194/cp-16-819-2020, 2020
Short summary
Short summary
A 1750 m ice core at the South Pole was recently drilled. The oldest ice is ~55 000 years old. Since ice at the South Pole flows at 10 m per year, the ice in the core originated upstream, where the climate is different. We made measurements of the ice flow, snow accumulation, and temperature upstream. We determined the ice came from ~150 km away near the Titan Dome where the accumulation rate was similar but the temperature was colder. Our measurements improve the interpretation of the ice core.
Alex Brisbourne, Bernd Kulessa, Thomas Hudson, Lianne Harrison, Paul Holland, Adrian Luckman, Suzanne Bevan, David Ashmore, Bryn Hubbard, Emma Pearce, James White, Adam Booth, Keith Nicholls, and Andrew Smith
Earth Syst. Sci. Data, 12, 887–896, https://doi.org/10.5194/essd-12-887-2020, https://doi.org/10.5194/essd-12-887-2020, 2020
Short summary
Short summary
Melting of the Larsen C Ice Shelf in Antarctica may lead to its collapse. To help estimate its lifespan we need to understand how the ocean can circulate beneath. This requires knowledge of the geometry of the sub-shelf cavity. New and existing measurements of seabed depth are integrated to produce a map of the ocean cavity beneath the ice shelf. The observed deep seabed may provide a pathway for circulation of warm ocean water but at the same time reduce rapid tidal melt at a critical location.
David E. Shean, Ian R. Joughin, Pierre Dutrieux, Benjamin E. Smith, and Etienne Berthier
The Cryosphere, 13, 2633–2656, https://doi.org/10.5194/tc-13-2633-2019, https://doi.org/10.5194/tc-13-2633-2019, 2019
Short summary
Short summary
We produced an 8-year, high-resolution DEM record for Pine Island Glacier (PIG), a site of substantial Antarctic mass loss in recent decades. We developed methods to study the spatiotemporal evolution of ice shelf basal melting, which is responsible for ~ 60 % of PIG mass loss. We present shelf-wide basal melt rates and document relative melt rates for kilometer-scale basal channels and keels, offering new indirect observations of ice–ocean interaction beneath a vulnerable ice shelf.
Dominic A. Winski, Tyler J. Fudge, David G. Ferris, Erich C. Osterberg, John M. Fegyveresi, Jihong Cole-Dai, Zayta Thundercloud, Thomas S. Cox, Karl J. Kreutz, Nikolas Ortman, Christo Buizert, Jenna Epifanio, Edward J. Brook, Ross Beaudette, Jeffrey Severinghaus, Todd Sowers, Eric J. Steig, Emma C. Kahle, Tyler R. Jones, Valerie Morris, Murat Aydin, Melinda R. Nicewonger, Kimberly A. Casey, Richard B. Alley, Edwin D. Waddington, Nels A. Iverson, Nelia W. Dunbar, Ryan C. Bay, Joseph M. Souney, Michael Sigl, and Joseph R. McConnell
Clim. Past, 15, 1793–1808, https://doi.org/10.5194/cp-15-1793-2019, https://doi.org/10.5194/cp-15-1793-2019, 2019
Short summary
Short summary
A deep ice core was recently drilled at the South Pole to understand past variations in the Earth's climate. To understand the information contained within the ice, we present the relationship between the depth and age of the ice in the South Pole Ice Core. We found that the oldest ice in our record is from 54 302 ± 519 years ago. Our results show that, on average, 7.4 cm of snow falls at the South Pole each year.
Robert Tardif, Gregory J. Hakim, Walter A. Perkins, Kaleb A. Horlick, Michael P. Erb, Julien Emile-Geay, David M. Anderson, Eric J. Steig, and David Noone
Clim. Past, 15, 1251–1273, https://doi.org/10.5194/cp-15-1251-2019, https://doi.org/10.5194/cp-15-1251-2019, 2019
Short summary
Short summary
An updated Last Millennium Reanalysis is presented, using an expanded multi-proxy database, and proxy models representing the seasonal characteristics of proxy records, in addition to the dual sensitivity to temperature and moisture of tree-ring-width chronologies. We show enhanced skill in spatial reconstructions of key climate variables in the updated reanalysis, compared to an earlier version, resulting from the combined influences of the enhanced proxy network and improved proxy modeling.
Chen Cheng, Adrian Jenkins, Paul R. Holland, Zhaomin Wang, Chengyan Liu, and Ruibin Xia
The Cryosphere, 13, 265–280, https://doi.org/10.5194/tc-13-265-2019, https://doi.org/10.5194/tc-13-265-2019, 2019
Short summary
Short summary
The sub-ice platelet layer (SIPL) under fast ice is most prevalent in McMurdo Sound, Antarctica. Using a modified plume model, we investigated the responses of SIPL thickening rate and frazil concentration to variations in ice shelf water supercooling in McMurdo Sound. It would be key to parameterizing the relevant process in more complex three-dimensional, primitive equation ocean models, which relies on the knowledge of the suspended frazil size spectrum within the ice–ocean boundary layer.
Frazer D. W. Christie, Robert G. Bingham, Noel Gourmelen, Eric J. Steig, Rosie R. Bisset, Hamish D. Pritchard, Kate Snow, and Simon F. B. Tett
The Cryosphere, 12, 2461–2479, https://doi.org/10.5194/tc-12-2461-2018, https://doi.org/10.5194/tc-12-2461-2018, 2018
Short summary
Short summary
With a focus on the hitherto little-studied Marie Byrd Land coastline linking Antarctica's more comprehensively studied Amundsen and Ross Sea Embayments, this paper uses both satellite remote sensing (Landsat, ASTER, ICESat, and CryoSat2) and climate and ocean records (i.e. ERA-Interim, Met Office EN4 data) to examine links between ice recession, inter-decadal atmosphere-ocean forcing and other influences acting upon the Pacific-facing coastline of West Antarctica.
Nancy A. N. Bertler, Howard Conway, Dorthe Dahl-Jensen, Daniel B. Emanuelsson, Mai Winstrup, Paul T. Vallelonga, James E. Lee, Ed J. Brook, Jeffrey P. Severinghaus, Taylor J. Fudge, Elizabeth D. Keller, W. Troy Baisden, Richard C. A. Hindmarsh, Peter D. Neff, Thomas Blunier, Ross Edwards, Paul A. Mayewski, Sepp Kipfstuhl, Christo Buizert, Silvia Canessa, Ruzica Dadic, Helle A. Kjær, Andrei Kurbatov, Dongqi Zhang, Edwin D. Waddington, Giovanni Baccolo, Thomas Beers, Hannah J. Brightley, Lionel Carter, David Clemens-Sewall, Viorela G. Ciobanu, Barbara Delmonte, Lukas Eling, Aja Ellis, Shruthi Ganesh, Nicholas R. Golledge, Skylar Haines, Michael Handley, Robert L. Hawley, Chad M. Hogan, Katelyn M. Johnson, Elena Korotkikh, Daniel P. Lowry, Darcy Mandeno, Robert M. McKay, James A. Menking, Timothy R. Naish, Caroline Noerling, Agathe Ollive, Anaïs Orsi, Bernadette C. Proemse, Alexander R. Pyne, Rebecca L. Pyne, James Renwick, Reed P. Scherer, Stefanie Semper, Marius Simonsen, Sharon B. Sneed, Eric J. Steig, Andrea Tuohy, Abhijith Ulayottil Venugopal, Fernando Valero-Delgado, Janani Venkatesh, Feitang Wang, Shimeng Wang, Dominic A. Winski, V. Holly L. Winton, Arran Whiteford, Cunde Xiao, Jiao Yang, and Xin Zhang
Clim. Past, 14, 193–214, https://doi.org/10.5194/cp-14-193-2018, https://doi.org/10.5194/cp-14-193-2018, 2018
Short summary
Short summary
Temperature and snow accumulation records from the annually dated Roosevelt Island Climate Evolution (RICE) ice core show that for the past 2 700 years, the eastern Ross Sea warmed, while the western Ross Sea showed no trend and West Antarctica cooled. From the 17th century onwards, this dipole relationship changed. Now all three regions show concurrent warming, with snow accumulation declining in West Antarctica and the eastern Ross Sea.
Hansi K. A. Singh, Gregory J. Hakim, Robert Tardif, Julien Emile-Geay, and David C. Noone
Clim. Past, 14, 157–174, https://doi.org/10.5194/cp-14-157-2018, https://doi.org/10.5194/cp-14-157-2018, 2018
Short summary
Short summary
The Atlantic Multidecadal Oscillation (AMO) is prominent in the climate system. We study the AMO over the last 2000 years using a novel proxy framework, the Last Millennium Reanalysis. We find that the AMO is linked to continental warming, Arctic sea ice retreat, and an Atlantic precipitation shift. Low clouds decrease globally. We find no distinct multidecadal spectral peak in the AMO over the last 2 millennia, suggesting that human activities may have enhanced the AMO in the modern era.
Alek A. Petty, Julienne C. Stroeve, Paul R. Holland, Linette N. Boisvert, Angela C. Bliss, Noriaki Kimura, and Walter N. Meier
The Cryosphere, 12, 433–452, https://doi.org/10.5194/tc-12-433-2018, https://doi.org/10.5194/tc-12-433-2018, 2018
Short summary
Short summary
There was significant scientific and media attention surrounding Arctic sea ice in 2016, due primarily to the record-warm air temperatures and low sea ice conditions observed at the start of the year. Here we quantify and assess the record-low monthly sea ice cover in winter, spring and fall, and the lack of record-low sea ice conditions in summer. We explore the primary drivers of these monthly sea ice states and explore the implications for improved summer sea ice forecasting.
Barbara Stenni, Mark A. J. Curran, Nerilie J. Abram, Anais Orsi, Sentia Goursaud, Valerie Masson-Delmotte, Raphael Neukom, Hugues Goosse, Dmitry Divine, Tas van Ommen, Eric J. Steig, Daniel A. Dixon, Elizabeth R. Thomas, Nancy A. N. Bertler, Elisabeth Isaksson, Alexey Ekaykin, Martin Werner, and Massimo Frezzotti
Clim. Past, 13, 1609–1634, https://doi.org/10.5194/cp-13-1609-2017, https://doi.org/10.5194/cp-13-1609-2017, 2017
Short summary
Short summary
Within PAGES Antarctica2k, we build an enlarged database of ice core water stable isotope records. We produce isotopic composites and temperature reconstructions since 0 CE for seven distinct Antarctic regions. We find a significant cooling trend from 0 to 1900 CE across all regions. Since 1900 CE, significant warming trends are identified for three regions. Only for the Antarctic Peninsula is this most recent century-scale trend unusual in the context of last-2000-year natural variability.
Walter A. Perkins and Gregory J. Hakim
Clim. Past, 13, 421–436, https://doi.org/10.5194/cp-13-421-2017, https://doi.org/10.5194/cp-13-421-2017, 2017
Short summary
Short summary
We examine the skill of a novel data assimilation approach to paleoclimate reconstruction that uses linear climate model forecasts. Many reconstruction studies forego the use of forecasts from climate models due to their high computational expense and relatively low skill. We show that the use of simpler linear models can improve reconstruction skill for both global mean temperature and spatial fields. Improvements displayed seem to be related to dynamical constraints from the forecasts.
Tyler R. Jones, James W. C. White, Eric J. Steig, Bruce H. Vaughn, Valerie Morris, Vasileios Gkinis, Bradley R. Markle, and Spruce W. Schoenemann
Atmos. Meas. Tech., 10, 617–632, https://doi.org/10.5194/amt-10-617-2017, https://doi.org/10.5194/amt-10-617-2017, 2017
Short summary
Short summary
New measurement systems have been developed that continuously melt ice core samples, in contrast to other methods that analyze a single sample at a time. These newer systems are capable of reducing analysis time by many years and improving data set resolution. In this study, we introduce improved methodologies that optimize the speed, accuracy, and precision of a water isotope continuous-flow system. The presented system will be used for Antarctic and Greenland ice core projects.
Xylar S. Asay-Davis, Stephen L. Cornford, Gaël Durand, Benjamin K. Galton-Fenzi, Rupert M. Gladstone, G. Hilmar Gudmundsson, Tore Hattermann, David M. Holland, Denise Holland, Paul R. Holland, Daniel F. Martin, Pierre Mathiot, Frank Pattyn, and Hélène Seroussi
Geosci. Model Dev., 9, 2471–2497, https://doi.org/10.5194/gmd-9-2471-2016, https://doi.org/10.5194/gmd-9-2471-2016, 2016
Short summary
Short summary
Coupled ice sheet–ocean models capable of simulating moving grounding lines are just becoming available. Such models have a broad range of potential applications in studying the dynamics of ice sheets and glaciers, including assessing their contributions to sea level change. Here we describe the idealized experiments that make up three interrelated Model Intercomparison Projects (MIPs) for marine ice sheet models and regional ocean circulation models incorporating ice shelf cavities.
Nathan Steiger and Gregory Hakim
Clim. Past, 12, 1375–1388, https://doi.org/10.5194/cp-12-1375-2016, https://doi.org/10.5194/cp-12-1375-2016, 2016
Short summary
Short summary
We present a data assimilation algorithm that incorporates proxy data at arbitrary timescales. Within a synthetic-test framework, we find that atmosphere–ocean states are most skillfully reconstructed by incorporating proxies across multiple timescales compared to using them at short or long timescales alone. Additionally, reconstructions that incorporate long-timescale proxies improve the low-frequency components of the reconstructions relative to using only high-resolution proxies.
D. Jansen, A. J. Luckman, A. Cook, S. Bevan, B. Kulessa, B. Hubbard, and P. R. Holland
The Cryosphere, 9, 1223–1227, https://doi.org/10.5194/tc-9-1223-2015, https://doi.org/10.5194/tc-9-1223-2015, 2015
Short summary
Short summary
Within the last year, a large rift in the southern part of the Larsen C Ice Shelf, Antarctic Peninsula, propagated towards the inner part of the ice shelf. In this study we present the development of the rift as derived from remote sensing data and assess the impact of possible calving scenarios on the future stability of the Larsen C Ice Shelf, using a numerical model. We find that the calving front is likely to become unstable after the anticipated calving events.
C. Buizert, K. M. Cuffey, J. P. Severinghaus, D. Baggenstos, T. J. Fudge, E. J. Steig, B. R. Markle, M. Winstrup, R. H. Rhodes, E. J. Brook, T. A. Sowers, G. D. Clow, H. Cheng, R. L. Edwards, M. Sigl, J. R. McConnell, and K. C. Taylor
Clim. Past, 11, 153–173, https://doi.org/10.5194/cp-11-153-2015, https://doi.org/10.5194/cp-11-153-2015, 2015
L. Geng, J. Cole-Dai, B. Alexander, J. Erbland, J. Savarino, A. J. Schauer, E. J. Steig, P. Lin, Q. Fu, and M. C. Zatko
Atmos. Chem. Phys., 14, 13361–13376, https://doi.org/10.5194/acp-14-13361-2014, https://doi.org/10.5194/acp-14-13361-2014, 2014
Short summary
Short summary
Examinations on snowpit and firn core results from Summit, Greenland suggest that there are two mechanisms leading to the observed double nitrate peaks in some years in the industrial era: 1) long-rang transport of nitrate and 2) enhanced local photochemical production of nitrate. Both of these mechanisms are related to pollution transport, as the additional nitrate from either direct transport or enhanced local photochemistry requires enhanced nitrogen sources from anthropogenic emissions.
E. J. Steig, V. Gkinis, A. J. Schauer, S. W. Schoenemann, K. Samek, J. Hoffnagle, K. J. Dennis, and S. M. Tan
Atmos. Meas. Tech., 7, 2421–2435, https://doi.org/10.5194/amt-7-2421-2014, https://doi.org/10.5194/amt-7-2421-2014, 2014
B. Medley, I. Joughin, B. E. Smith, S. B. Das, E. J. Steig, H. Conway, S. Gogineni, C. Lewis, A. S. Criscitiello, J. R. McConnell, M. R. van den Broeke, J. T. M. Lenaerts, D. H. Bromwich, J. P. Nicolas, and C. Leuschen
The Cryosphere, 8, 1375–1392, https://doi.org/10.5194/tc-8-1375-2014, https://doi.org/10.5194/tc-8-1375-2014, 2014
E. D. Sofen, B. Alexander, E. J. Steig, M. H. Thiemens, S. A. Kunasek, H. M. Amos, A. J. Schauer, M. G. Hastings, J. Bautista, T. L. Jackson, L. E. Vogel, J. R. McConnell, D. R. Pasteris, and E. S. Saltzman
Atmos. Chem. Phys., 14, 5749–5769, https://doi.org/10.5194/acp-14-5749-2014, https://doi.org/10.5194/acp-14-5749-2014, 2014
A. A. Petty, P. R. Holland, and D. L. Feltham
The Cryosphere, 8, 761–783, https://doi.org/10.5194/tc-8-761-2014, https://doi.org/10.5194/tc-8-761-2014, 2014
A. M. Brisbourne, A. M. Smith, E. C. King, K. W. Nicholls, P. R. Holland, and K. Makinson
The Cryosphere, 8, 1–13, https://doi.org/10.5194/tc-8-1-2014, https://doi.org/10.5194/tc-8-1-2014, 2014
P. Dutrieux, D. G. Vaughan, H. F. J. Corr, A. Jenkins, P. R. Holland, I. Joughin, and A. H. Fleming
The Cryosphere, 7, 1543–1555, https://doi.org/10.5194/tc-7-1543-2013, https://doi.org/10.5194/tc-7-1543-2013, 2013
Related subject area
Discipline: Ice sheets | Subject: Antarctic
A model framework for atmosphere–snow water vapor exchange and the associated isotope effects at Dome Argus, Antarctica – Part 1: The diurnal changes
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?
Feedback mechanisms controlling Antarctic glacial-cycle dynamics simulated with a coupled ice sheet–solid Earth model
The effect of ice shelf rheology on shelf edge bending
Hysteresis of idealized, instability-prone outlet glaciers in response to pinning-point buttressing variation
A physics-based Antarctic melt detection technique: combining Advanced Microwave Scanning Radiometer 2, radiative-transfer modeling, and firn modeling
Brief communication: Precision measurement of the index of refraction of deep glacial ice at radio frequencies at Summit Station, Greenland
Widespread increase in discharge from west Antarctic Peninsula glaciers since 2018
Surface dynamics and history of the calving cycle of Astrolabe Glacier (Adélie Coast, Antarctica) derived from satellite imagery
Weak relationship between remotely detected crevasses and inferred ice rheological parameters on Antarctic ice shelves
Extensive palaeo-surfaces beneath the Evans–Rutford region of the West Antarctic Ice Sheet control modern and past ice flow
Towards the systematic reconnaissance of seismic signals from glaciers and ice sheets – Part 1: Event detection for cryoseismology
Towards the systematic reconnaissance of seismic signals from glaciers and ice sheets – Part 2: Unsupervised learning for source process characterization
Geometric amplification and suppression of ice-shelf basal melt in West Antarctica
Basal channels, ice thinning and grounding zone retreat at Thwaites Glacier, West Antarctica
Alpine topography of the Gamburtsev Subglacial Mountains, Antarctica, mapped from ice sheet surface morphology
Melt sensitivity of irreversible retreat of Pine Island Glacier
A fast and unified subglacial hydrological model applied to Thwaites Glacier, Antarctica
Impact of boundary conditions on the modeled thermal regime of the Antarctic ice sheet
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
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
The evolution of future Antarctic surface melt using PISM-dEBM-simple
Sensitivity of the MAR regional climate model snowpack to the parameterization of the assimilation of satellite-derived wet-snow masks on the Antarctic Peninsula
Stratigraphic noise and its potential drivers across the plateau of Dronning Maud Land, East Antarctica
Modes of Antarctic tidal grounding line migration revealed by Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) laser altimetry
Evaluating the impact of enhanced horizontal resolution over the Antarctic domain using a variable-resolution Earth system model
Statistically parameterizing and evaluating a positive degree-day model to estimate surface melt in Antarctica from 1979 to 2022
Widespread slowdown in thinning rates of West Antarctic ice shelves
Seasonal variability in Antarctic ice shelf velocities forced by sea surface height variations
Revisiting temperature sensitivity: how does Antarctic precipitation change with temperature?
Cosmogenic-nuclide data from Antarctic nunataks can constrain past ice sheet instabilities
Exploring ice sheet model sensitivity to ocean thermal forcing and basal sliding using the Community Ice Sheet Model (CISM)
High mid-Holocene accumulation rates over West Antarctica inferred from a pervasive ice-penetrating radar reflector
Seasonal and interannual variability of the landfast ice mass balance between 2009 and 2018 in Prydz Bay, East Antarctica
Megadunes in Antarctica: migration and characterization from remote and in situ observations
Slowdown of Shirase Glacier, East Antarctica, caused by strengthening alongshore winds
Timescales of outlet-glacier flow with negligible basal friction: theory, observations and modeling
Antarctic contribution to future sea level from ice shelf basal melt as constrained by ice discharge observations
Anthropogenic and internal drivers of wind changes over the Amundsen Sea, West Antarctica, during the 20th and 21st centuries
New 10Be exposure ages improve Holocene ice sheet thinning history near the grounding line of Pope Glacier, Antarctica
Antarctic surface climate and surface mass balance in the Community Earth System Model version 2 during the satellite era and into the future (1979–2100)
Tianming Ma, Zhuang Jiang, Minghu Ding, Pengzhen He, Yuansheng Li, Wenqian Zhang, and Lei Geng
The Cryosphere, 18, 4547–4565, https://doi.org/10.5194/tc-18-4547-2024, https://doi.org/10.5194/tc-18-4547-2024, 2024
Short summary
Short summary
We constructed a box model to evaluate the isotope effects of atmosphere–snow water vapor exchange at Dome A, Antarctica. The results show clear and invisible diurnal changes in surface snow isotopes under summer and winter conditions, respectively. The model also predicts that the annual net effects of atmosphere–snow water vapor exchange would be overall enrichments in snow isotopes since the effects in summer appear to be greater than those in winter at the study site.
Ann Kristin Klose, Violaine Coulon, Frank Pattyn, and Ricarda Winkelmann
The Cryosphere, 18, 4463–4492, https://doi.org/10.5194/tc-18-4463-2024, https://doi.org/10.5194/tc-18-4463-2024, 2024
Short summary
Short summary
We systematically assess the long-term sea-level response from Antarctica to warming projected over the next centuries, using two ice-sheet models. We show that this committed Antarctic sea-level contribution is substantially higher than the transient sea-level change projected for the coming decades. A low-emission scenario already poses considerable risk of multi-meter sea-level increase over the next millennia, while additional East Antarctic ice loss unfolds under the high-emission pathway.
Christian Wirths, Thomas F. Stocker, and Johannes C. R. Sutter
The Cryosphere, 18, 4435–4462, https://doi.org/10.5194/tc-18-4435-2024, https://doi.org/10.5194/tc-18-4435-2024, 2024
Short summary
Short summary
We investigated the influence of several regional climate models on the Antarctic Ice Sheet when applied as forcing for the Parallel Ice Sheet Model (PISM). Our study shows that the choice of regional climate model forcing results in uncertainties of around a tenth of those in future sea level rise projections and also affects the extent of grounding line retreat in West Antarctica.
Maria T. Kappelsberger, Martin Horwath, Eric Buchta, Matthias O. Willen, Ludwig Schröder, Sanne B. M. Veldhuijsen, Peter Kuipers Munneke, and Michiel R. van den Broeke
The Cryosphere, 18, 4355–4378, https://doi.org/10.5194/tc-18-4355-2024, https://doi.org/10.5194/tc-18-4355-2024, 2024
Short summary
Short summary
The interannual variations in the height of the Antarctic Ice Sheet (AIS) are mainly due to natural variations in snowfall. Precise knowledge of these variations is important for the detection of any long-term climatic trends in AIS surface elevation. We present a new product that spatially resolves these height variations over the period 1992–2017. The product combines the strengths of atmospheric modeling results and satellite altimetry measurements.
Torsten Albrecht, Meike Bagge, and Volker Klemann
The Cryosphere, 18, 4233–4255, https://doi.org/10.5194/tc-18-4233-2024, https://doi.org/10.5194/tc-18-4233-2024, 2024
Short summary
Short summary
We performed coupled ice sheet–solid Earth simulations and discovered a positive (forebulge) feedback mechanism for advancing grounding lines, supporting a larger West Antarctic Ice Sheet during the Last Glacial Maximum. During deglaciation we found that the stabilizing glacial isostatic adjustment feedback dominates grounding-line retreat in the Ross Sea, with a weak Earth structure. This may have consequences for present and future ice sheet stability and potential rates of sea-level rise.
W. Roger Buck
The Cryosphere, 18, 4165–4176, https://doi.org/10.5194/tc-18-4165-2024, https://doi.org/10.5194/tc-18-4165-2024, 2024
Short summary
Short summary
Standard theory predicts that the edge of an ice shelf should bend downward. Satellite observations show that the edges of many ice shelves bend upward. A new theory for ice shelf bending is developed that, for the first time, includes the kind of vertical variations in ice flow properties expected for ice shelves. Upward bending of shelf edges is predicted as long as the ice surface is very cold and the ice flow properties depend strongly on temperature.
Johannes Feldmann, Anders Levermann, and Ricarda Winkelmann
The Cryosphere, 18, 4011–4028, https://doi.org/10.5194/tc-18-4011-2024, https://doi.org/10.5194/tc-18-4011-2024, 2024
Short summary
Short summary
Here we show in simplified simulations that the (ir)reversibility of the retreat of instability-prone, Antarctica-type glaciers can strongly depend on the depth of the bed depression they rest on. If it is sufficiently deep, then the destabilized glacier does not recover from its collapsed state. Our results suggest that glaciers resting on a wide and deep bed depression, such as Antarctica's Thwaites Glacier, are particularly susceptible to irreversible retreat.
Marissa E. Dattler, Brooke Medley, and C. Max Stevens
The Cryosphere, 18, 3613–3631, https://doi.org/10.5194/tc-18-3613-2024, https://doi.org/10.5194/tc-18-3613-2024, 2024
Short summary
Short summary
We developed an algorithm based on combining models and satellite observations to identify the presence of surface melt on the Antarctic Ice Sheet. We find that this method works similarly to previous methods by assessing 13 sites and the Larsen C ice shelf. Unlike previous methods, this algorithm is based on physical parameters, and updates to this method could allow the meltwater present on the Antarctic Ice Sheet to be quantified instead of simply detected.
Christoph Welling and The RNO-G Collaboration
The Cryosphere, 18, 3433–3437, https://doi.org/10.5194/tc-18-3433-2024, https://doi.org/10.5194/tc-18-3433-2024, 2024
Short summary
Short summary
We report on the measurement of the index of refraction in glacial ice at radio frequencies. We show that radio echoes from within the ice can be associated with specific features of the ice conductivity and use this to determine the wave velocity. This measurement is especially relevant for the Radio Neutrino Observatory Greenland (RNO-G), a neutrino detection experiment currently under construction at Summit Station, Greenland.
Benjamin J. Davison, Anna E. Hogg, Carlos Moffat, Michael P. Meredith, and Benjamin J. Wallis
The Cryosphere, 18, 3237–3251, https://doi.org/10.5194/tc-18-3237-2024, https://doi.org/10.5194/tc-18-3237-2024, 2024
Short summary
Short summary
Using a new dataset of ice motion, we observed glacier acceleration on the west coast of the Antarctic Peninsula. The speed-up began around January 2021, but some glaciers sped up earlier or later. Using a combination of ship-based ocean temperature observations and climate models, we show that the speed-up coincided with a period of unusually warm air and ocean temperatures in the region.
Floriane Provost, Dimitri Zigone, Emmanuel Le Meur, Jean-Philippe Malet, and Clément Hibert
The Cryosphere, 18, 3067–3079, https://doi.org/10.5194/tc-18-3067-2024, https://doi.org/10.5194/tc-18-3067-2024, 2024
Short summary
Short summary
The recent calving of Astrolabe Glacier in November 2021 presents an opportunity to better understand the processes leading to ice fracturing. Optical-satellite imagery is used to retrieve the calving cycle of the glacier ice tongue and to measure the ice velocity and strain rates in order to document fracture evolution. We observed that the presence of sea ice for consecutive years has favoured the glacier extension but failed to inhibit the growth of fractures that accelerated in June 2021.
Cristina Gerli, Sebastian Rosier, G. Hilmar Gudmundsson, and Sainan Sun
The Cryosphere, 18, 2677–2689, https://doi.org/10.5194/tc-18-2677-2024, https://doi.org/10.5194/tc-18-2677-2024, 2024
Short summary
Short summary
Recent efforts have focused on using AI and satellite imagery to track crevasses for assessing ice shelf damage and informing ice flow models. Our study reveals a weak connection between these observed products and damage maps inferred from ice flow models. While there is some improvement in crevasse-dense regions, this association remains limited. Directly mapping ice damage from satellite observations may not significantly improve the representation of these processes within ice flow models.
Charlotte M. Carter, Michael J. Bentley, Stewart S. R. Jamieson, Guy J. G. Paxman, Tom A. Jordan, Julien A. Bodart, Neil Ross, and Felipe Napoleoni
The Cryosphere, 18, 2277–2296, https://doi.org/10.5194/tc-18-2277-2024, https://doi.org/10.5194/tc-18-2277-2024, 2024
Short summary
Short summary
We use radio-echo sounding data to investigate the presence of flat surfaces beneath the Evans–Rutford region in West Antarctica. These surfaces may be what remains of laterally continuous surfaces, formed before the inception of the West Antarctic Ice Sheet, and we assess two hypotheses for their formation. Tectonic structures in the region may have also had a control on the growth of the ice sheet by focusing ice flow into troughs adjoining these surfaces.
Rebecca B. Latto, Ross J. Turner, Anya M. Reading, and J. Paul Winberry
The Cryosphere, 18, 2061–2079, https://doi.org/10.5194/tc-18-2061-2024, https://doi.org/10.5194/tc-18-2061-2024, 2024
Short summary
Short summary
The study of icequakes allows for investigation of many glacier processes that are unseen by typical reconnaissance methods. However, detection of such seismic signals is challenging due to low signal-to-noise levels and diverse source mechanisms. Here we present a novel algorithm that is optimized to detect signals from a glacier environment. We apply the algorithm to seismic data recorded in the 2010–2011 austral summer from the Whillans Ice Stream and evaluate the resulting event catalogue.
Rebecca B. Latto, Ross J. Turner, Anya M. Reading, Sue Cook, Bernd Kulessa, and J. Paul Winberry
The Cryosphere, 18, 2081–2101, https://doi.org/10.5194/tc-18-2081-2024, https://doi.org/10.5194/tc-18-2081-2024, 2024
Short summary
Short summary
Seismic catalogues are potentially rich sources of information on glacier processes. In a companion study, we constructed an event catalogue for seismic data from the Whillans Ice Stream. Here, we provide a semi-automated workflow for consistent catalogue analysis using an unsupervised cluster analysis. We discuss the defining characteristics of identified signal types found in this catalogue and possible mechanisms for the underlying glacier processes and noise sources.
Jan De Rydt and Kaitlin Naughten
The Cryosphere, 18, 1863–1888, https://doi.org/10.5194/tc-18-1863-2024, https://doi.org/10.5194/tc-18-1863-2024, 2024
Short summary
Short summary
The West Antarctic Ice Sheet is losing ice at an accelerating pace. This is largely due to the presence of warm ocean water around the periphery of the Antarctic continent, which melts the ice. It is generally assumed that the strength of this process is controlled by the temperature of the ocean. However, in this study we show that an equally important role is played by the changing geometry of the ice sheet, which affects the strength of the ocean currents and thereby the melt rates.
Allison M. Chartrand, Ian M. Howat, Ian R. Joughin, and Benjamin E. Smith
EGUsphere, https://doi.org/10.5194/egusphere-2024-1132, https://doi.org/10.5194/egusphere-2024-1132, 2024
Short summary
Short summary
This study uses high-resolution remote sensing data to show that shrinking of the West Antarctic Thwaites Glacier’s ice shelf (floating extension) is exacerbated by the presence of sub–ice shelf meltwater channels that form as the glacier transitions from full contact with the bed 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.
Edmund J. Lea, Stewart S. R. Jamieson, and Michael J. Bentley
The Cryosphere, 18, 1733–1751, https://doi.org/10.5194/tc-18-1733-2024, https://doi.org/10.5194/tc-18-1733-2024, 2024
Short summary
Short summary
We use the ice surface expression of the Gamburtsev Subglacial Mountains in East Antarctica to map the horizontal pattern of valleys and ridges in finer detail than possible from previous methods. In upland areas, valleys are spaced much less than 5 km apart, with consequences for the distribution of melting at the bed and hence the likelihood of ancient ice being preserved. Automated mapping techniques were tested alongside manual approaches, with a hybrid approach recommended for future work.
Brad Reed, J. A. Mattias Green, Adrian Jenkins, and G. Hilmar Gudmundsson
EGUsphere, https://doi.org/10.5194/egusphere-2024-673, https://doi.org/10.5194/egusphere-2024-673, 2024
Short summary
Short summary
We use a numerical ice-flow model to simulate the response of a 1940s Pine Island Glacier to changes in melting beneath its ice shelf. A decadal period of warm forcing is sufficient to push the glacier into an unstable, irreversible retreat from its long-term position on a subglacial ridge to an upstream ice plain. This retreat can only be stopped when unrealistic cold forcing is applied. These results show that short warm anomalies can lead to quick and substantial increases in ice flux.
Elise Kazmierczak, Thomas Gregov, Violaine Coulon, and Frank Pattyn
EGUsphere, https://doi.org/10.5194/egusphere-2024-466, https://doi.org/10.5194/egusphere-2024-466, 2024
Short summary
Short summary
We introduce a new fast model for the water flow beneath the ice sheet capable of handling in a unified way various hydrological and bed conditions. 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 both the efficiency of the drainage and the bed type.
In-Woo Park, Emilia Kyung Jin, Mathieu Morlighem, and Kang-Kun Lee
The Cryosphere, 18, 1139–1155, https://doi.org/10.5194/tc-18-1139-2024, https://doi.org/10.5194/tc-18-1139-2024, 2024
Short summary
Short summary
This study conducted 3D thermodynamic ice sheet model experiments, and modeled temperatures were compared with 15 observed borehole temperature profiles. We found that using incompressibility of ice without sliding agrees well with observed temperature profiles in slow-flow regions, while incorporating sliding in fast-flow regions captures observed temperature profiles. Also, the choice of vertical velocity scheme has a greater impact on the shape of the modeled temperature profile.
Matthew A. Danielson and Philip J. Bart
The Cryosphere, 18, 1125–1138, https://doi.org/10.5194/tc-18-1125-2024, https://doi.org/10.5194/tc-18-1125-2024, 2024
Short summary
Short summary
The post-Last Glacial Maximum (LGM) retreat of the West Antarctic Ice Sheet in the Ross Sea was more significant than for any other Antarctic sector. Here we combined the available dates of retreat with new mapping of sediment deposited by the ice sheet during overall retreat. Our work shows that the post-LGM retreat through the Ross Sea was not uniform. This uneven retreat can cause instability in the present-day Antarctic ice sheet configuration and lead to future runaway retreat.
Trystan Surawy-Stepney, Anna E. Hogg, Stephen L. Cornford, Benjamin J. Wallis, Benjamin J. Davison, Heather L. Selley, Ross A. W. Slater, Elise K. Lie, Livia Jakob, Andrew Ridout, Noel Gourmelen, Bryony I. D. Freer, Sally F. Wilson, and Andrew Shepherd
The Cryosphere, 18, 977–993, https://doi.org/10.5194/tc-18-977-2024, https://doi.org/10.5194/tc-18-977-2024, 2024
Short summary
Short summary
Here, we use satellite observations and an ice flow model to quantify the impact of sea ice buttressing on ice streams on the Antarctic Peninsula. The evacuation of 11-year-old landfast sea ice in the Larsen B embayment on the East Antarctic Peninsula in January 2022 was closely followed by major changes in the calving behaviour and acceleration (30 %) of the ocean-terminating glaciers. Our results show that sea ice buttressing had a negligible direct role in the observed dynamic changes.
Andrew N. Hennig, David A. Mucciarone, Stanley S. Jacobs, Richard A. Mortlock, and Robert B. Dunbar
The Cryosphere, 18, 791–818, https://doi.org/10.5194/tc-18-791-2024, https://doi.org/10.5194/tc-18-791-2024, 2024
Short summary
Short summary
A total of 937 seawater paired oxygen isotope (δ18O)–salinity samples collected during seven cruises on the SE Amundsen Sea between 1994 and 2020 reveal a deep freshwater source with δ18O − 29.4±1.0‰, consistent with the signature of local ice shelf melt. Local mean meteoric water content – comprised primarily of glacial meltwater – increased between 1994 and 2020 but exhibited greater interannual variability than increasing trend.
Qinggang Gao, Louise C. Sime, Alison J. McLaren, Thomas J. Bracegirdle, Emilie Capron, Rachael H. Rhodes, Hans Christian Steen-Larsen, Xiaoxu Shi, and Martin Werner
The Cryosphere, 18, 683–703, https://doi.org/10.5194/tc-18-683-2024, https://doi.org/10.5194/tc-18-683-2024, 2024
Short summary
Short summary
Antarctic precipitation is a crucial component of the climate system. Its spatio-temporal variability impacts sea level changes and the interpretation of water isotope measurements in ice cores. To better understand its climatic drivers, we developed water tracers in an atmospheric model to identify moisture source conditions from which precipitation originates. We find that mid-latitude surface winds exert an important control on moisture availability for Antarctic precipitation.
Violaine Coulon, Ann Kristin Klose, Christoph Kittel, Tamsin Edwards, Fiona Turner, Ricarda Winkelmann, and Frank Pattyn
The Cryosphere, 18, 653–681, https://doi.org/10.5194/tc-18-653-2024, https://doi.org/10.5194/tc-18-653-2024, 2024
Short summary
Short summary
We present new projections of the evolution of the Antarctic ice sheet until the end of the millennium, calibrated with observations. We show that the ocean will be the main trigger of future ice loss. As temperatures continue to rise, the atmosphere's role may shift from mitigating to amplifying Antarctic mass loss already by the end of the century. For high-emission scenarios, this may lead to substantial sea-level rise. Adopting sustainable practices would however reduce the rate of ice loss.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
Ice-penetrating radar allows us to explore the internal structure of glaciers and ice sheets to constrain past and present ice-flow conditions. In this paper, we examine englacial layers within the Lambert Glacier in East Antarctica using a quantitative layer tracing tool. Analysis reveals that the ice flow here has been relatively stable, but evidence for former fast flow along a tributary suggests that changes have occurred in the past and could change again in the future.
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
Short summary
Short summary
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.
Julius Garbe, Maria Zeitz, Uta Krebs-Kanzow, and Ricarda Winkelmann
The Cryosphere, 17, 4571–4599, https://doi.org/10.5194/tc-17-4571-2023, https://doi.org/10.5194/tc-17-4571-2023, 2023
Short summary
Short summary
We adopt the novel surface module dEBM-simple in the Parallel Ice Sheet Model (PISM) to investigate the impact of atmospheric warming on Antarctic surface melt and long-term ice sheet dynamics. As an enhancement compared to traditional temperature-based melt schemes, the module accounts for changes in ice surface albedo and thus the melt–albedo feedback. Our results underscore the critical role of ice–atmosphere feedbacks in the future sea-level contribution of Antarctica on long timescales.
Thomas Dethinne, Quentin Glaude, Ghislain Picard, Christoph Kittel, Patrick Alexander, Anne Orban, and Xavier Fettweis
The Cryosphere, 17, 4267–4288, https://doi.org/10.5194/tc-17-4267-2023, https://doi.org/10.5194/tc-17-4267-2023, 2023
Short summary
Short summary
We investigate the sensitivity of the regional climate model
Modèle Atmosphérique Régional(MAR) to the assimilation of wet-snow occurrence estimated by remote sensing datasets. The assimilation is performed by nudging the MAR snowpack temperature. The data assimilation is performed over the Antarctic Peninsula for the 2019–2021 period. The results show an increase in the melt production (+66.7 %) and a decrease in surface mass balance (−4.5 %) of the model for the 2019–2020 melt season.
Nora Hirsch, Alexandra Zuhr, Thomas Münch, Maria Hörhold, Johannes Freitag, Remi Dallmayr, and Thomas Laepple
The Cryosphere, 17, 4207–4221, https://doi.org/10.5194/tc-17-4207-2023, https://doi.org/10.5194/tc-17-4207-2023, 2023
Short summary
Short summary
Stable water isotopes from firn cores provide valuable information on past climates, yet their utility is hampered by stratigraphic noise, i.e. the irregular deposition and wind-driven redistribution of snow. We found stratigraphic noise on the Antarctic Plateau to be related to the local accumulation rate, snow surface roughness and slope inclination, which can guide future decisions on sampling locations and thus increase the resolution of climate reconstructions from low-accumulation areas.
Bryony I. D. Freer, Oliver J. Marsh, Anna E. Hogg, Helen Amanda Fricker, and Laurie Padman
The Cryosphere, 17, 4079–4101, https://doi.org/10.5194/tc-17-4079-2023, https://doi.org/10.5194/tc-17-4079-2023, 2023
Short summary
Short summary
We develop a method using ICESat-2 data to measure how Antarctic grounding lines (GLs) migrate across the tide cycle. At an ice plain on the Ronne Ice Shelf we observe 15 km of tidal GL migration, the largest reported distance in Antarctica, dominating any signal of long-term migration. We identify four distinct migration modes, which provide both observational support for models of tidal ice flexure and GL migration and insights into ice shelf–ocean–subglacial interactions in grounding zones.
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
Short summary
Short summary
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.
Yaowen Zheng, Nicholas R. Golledge, Alexandra Gossart, Ghislain Picard, and Marion Leduc-Leballeur
The Cryosphere, 17, 3667–3694, https://doi.org/10.5194/tc-17-3667-2023, https://doi.org/10.5194/tc-17-3667-2023, 2023
Short summary
Short summary
Positive degree-day (PDD) schemes are widely used in many Antarctic numerical ice sheet models. However, the PDD approach has not been systematically explored for its application in Antarctica. We have constructed a novel grid-cell-level spatially distributed PDD (dist-PDD) model and assessed its accuracy. We suggest that an appropriately parameterized dist-PDD model can be a valuable tool for exploring Antarctic surface melt beyond the satellite era.
Fernando S. Paolo, Alex S. Gardner, Chad A. Greene, Johan Nilsson, Michael P. Schodlok, Nicole-Jeanne Schlegel, and Helen A. Fricker
The Cryosphere, 17, 3409–3433, https://doi.org/10.5194/tc-17-3409-2023, https://doi.org/10.5194/tc-17-3409-2023, 2023
Short summary
Short summary
We report on a slowdown in the rate of thinning and melting of West Antarctic ice shelves. We present a comprehensive assessment of the Antarctic ice shelves, where we analyze at a continental scale the changes in thickness, flow, and basal melt over the past 26 years. We also present a novel method to estimate ice shelf change from satellite altimetry and a time-dependent data set of ice shelf thickness and basal melt rates at an unprecedented resolution.
Cyrille Mosbeux, Laurie Padman, Emilie Klein, Peter D. Bromirski, and Helen A. Fricker
The Cryosphere, 17, 2585–2606, https://doi.org/10.5194/tc-17-2585-2023, https://doi.org/10.5194/tc-17-2585-2023, 2023
Short summary
Short summary
Antarctica's ice shelves (the floating extension of the ice sheet) help regulate ice flow. As ice shelves thin or lose contact with the bedrock, the upstream ice tends to accelerate, resulting in increased mass loss. Here, we use an ice sheet model to simulate the effect of seasonal sea surface height variations and see if we can reproduce observed seasonal variability of ice velocity on the ice shelf. When correctly parameterised, the model fits the observations well.
Lena Nicola, Dirk Notz, and Ricarda Winkelmann
The Cryosphere, 17, 2563–2583, https://doi.org/10.5194/tc-17-2563-2023, https://doi.org/10.5194/tc-17-2563-2023, 2023
Short summary
Short summary
For future sea-level projections, approximating Antarctic precipitation increases through temperature-scaling approaches will remain important, as coupled ice-sheet simulations with regional climate models remain computationally expensive, especially on multi-centennial timescales. We here revisit the relationship between Antarctic temperature and precipitation using different scaling approaches, identifying and explaining regional differences.
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
Short summary
Short summary
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.
Mira Berdahl, Gunter Leguy, William H. Lipscomb, Nathan M. Urban, and Matthew J. Hoffman
The Cryosphere, 17, 1513–1543, https://doi.org/10.5194/tc-17-1513-2023, https://doi.org/10.5194/tc-17-1513-2023, 2023
Short summary
Short summary
Contributions to future sea level from the Antarctic Ice Sheet remain poorly constrained. One reason is that ice sheet model initialization methods can have significant impacts on how the ice sheet responds to future forcings. We investigate the impacts of two key parameters used during model initialization. We find that these parameter choices alone can impact multi-century sea level rise by up to 2 m, emphasizing the need to carefully consider these choices for sea level rise predictions.
Julien A. Bodart, Robert G. Bingham, Duncan A. Young, Joseph A. MacGregor, David W. Ashmore, Enrica Quartini, Andrew S. Hein, David G. Vaughan, and Donald D. Blankenship
The Cryosphere, 17, 1497–1512, https://doi.org/10.5194/tc-17-1497-2023, https://doi.org/10.5194/tc-17-1497-2023, 2023
Short summary
Short summary
Estimating how West Antarctica will change in response to future climatic change depends on our understanding of past ice processes. Here, we use a reflector widely visible on airborne radar data across West Antarctica to estimate accumulation rates over the past 4700 years. By comparing our estimates with current atmospheric data, we find that accumulation rates were 18 % greater than modern rates. This has implications for our understanding of past ice processes in the region.
Na Li, Ruibo Lei, Petra Heil, Bin Cheng, Minghu Ding, Zhongxiang Tian, and Bingrui Li
The Cryosphere, 17, 917–937, https://doi.org/10.5194/tc-17-917-2023, https://doi.org/10.5194/tc-17-917-2023, 2023
Short summary
Short summary
The observed annual maximum landfast ice (LFI) thickness off Zhongshan (Davis) was 1.59±0.17 m (1.64±0.08 m). Larger interannual and local spatial variabilities for the seasonality of LFI were identified at Zhongshan, with the dominant influencing factors of air temperature anomaly, snow atop, local topography and wind regime, and oceanic heat flux. The variability of LFI properties across the study domain prevailed at interannual timescales, over any trend during the recent decades.
Giacomo Traversa, Davide Fugazza, and Massimo Frezzotti
The Cryosphere, 17, 427–444, https://doi.org/10.5194/tc-17-427-2023, https://doi.org/10.5194/tc-17-427-2023, 2023
Short summary
Short summary
Megadunes are fields of huge snow dunes present in Antarctica and on other planets, important as they present mass loss on the leeward side (glazed snow), on a continent characterized by mass gain. Here, we studied megadunes using remote data and measurements acquired during past field expeditions. We quantified their physical properties and migration and demonstrated that they migrate against slope and wind. We further proposed automatic detections of the glazed snow on their leeward side.
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
Short summary
Short summary
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.
Johannes Feldmann and Anders Levermann
The Cryosphere, 17, 327–348, https://doi.org/10.5194/tc-17-327-2023, https://doi.org/10.5194/tc-17-327-2023, 2023
Short summary
Short summary
Here we present a scaling relation that allows the comparison of the timescales of glaciers with geometric similarity. According to the relation, thicker and wider glaciers on a steeper bed slope have a much faster timescale than shallower, narrower glaciers on a flatter bed slope. The relation is supported by observations and simplified numerical simulations. We combine the scaling relation with a statistical analysis of the topography of 13 instability-prone Antarctic outlet glaciers.
Eveline C. van der Linden, Dewi Le Bars, Erwin Lambert, and Sybren Drijfhout
The Cryosphere, 17, 79–103, https://doi.org/10.5194/tc-17-79-2023, https://doi.org/10.5194/tc-17-79-2023, 2023
Short summary
Short summary
The Antarctic ice sheet (AIS) is the largest uncertainty in future sea level estimates. The AIS mainly loses mass through ice discharge, the transfer of land ice into the ocean. Ice discharge is triggered by warming ocean water (basal melt). New future estimates of AIS sea level contributions are presented in which basal melt is constrained with ice discharge observations. Despite the different methodology, the resulting projections are in line with previous multimodel assessments.
Paul R. Holland, Gemma K. O'Connor, Thomas J. Bracegirdle, Pierre Dutrieux, Kaitlin A. Naughten, Eric J. Steig, David P. Schneider, Adrian Jenkins, and James A. Smith
The Cryosphere, 16, 5085–5105, https://doi.org/10.5194/tc-16-5085-2022, https://doi.org/10.5194/tc-16-5085-2022, 2022
Short summary
Short summary
The Antarctic Ice Sheet is losing ice, causing sea-level rise. However, it is not known whether human-induced climate change has contributed to this ice loss. In this study, we use evidence from climate models and palaeoclimate measurements (e.g. ice cores) to suggest that the ice loss was triggered by natural climate variations but is now sustained by human-forced climate change. This implies that future greenhouse-gas emissions may influence sea-level rise from Antarctica.
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
Short summary
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.
Devon Dunmire, Jan T. M. Lenaerts, Rajashree Tri Datta, and Tessa Gorte
The Cryosphere, 16, 4163–4184, https://doi.org/10.5194/tc-16-4163-2022, https://doi.org/10.5194/tc-16-4163-2022, 2022
Short summary
Short summary
Earth system models (ESMs) are used to model the climate system and the interactions of its components (atmosphere, ocean, etc.) both historically and into the future under different assumptions of human activity. The representation of Antarctica in ESMs is important because it can inform projections of the ice sheet's contribution to sea level rise. Here, we compare output of Antarctica's surface climate from an ESM with observations to understand strengths and weaknesses within the model.
Cited articles
Alley, K. E., Wild, C. T., Luckman, A., Scambos, T. A., Truffer, M., Pettit, E. C., Muto, A., Wallin, B., Klinger, M., Sutterley, T., Child, S. F., Hulen, C., Lenaerts, J. T. M., Maclennan, M., Keenan, E., and Dunmire, D.: Two decades of dynamic change and progressive destabilization on the Thwaites Eastern Ice Shelf, The Cryosphere, 15, 5187–5203, https://doi.org/10.5194/tc-15-5187-2021, 2021.
Arblaster, J. M. and Meehl, G. A.: Contributions of external forcings to Southern Annular Mode trends, J. Climate, 19, 2896–2905, https://doi.org/10.1175/Jcli3774.1, 2006.
Assmann, K. M., Jenkins, A., Shoosmith, D. R., Walker, D. P., Jacobs, S. S., and Nicholls, K. W.: Variability of Circumpolar Deep Water transport onto the Amundsen Sea Continental shelf through a shelf break trough, J. Geophys. Res.-Oceans, 118, 6603–6620, https://doi.org/10.1002/2013JC008871, 2013.
Bracegirdle, T. J., Turner, J., Hosking, J. S., and Phillips, T.: Sources of uncertainty in projections of 21st century westerly wind changes over the Amundsen Sea, West Antarctica, in CMIP5 climate models, Clim. Dynam., 43, 2093–2104, https://doi.org/10.1007/s00382-013-2032-1, 2014.
Bracegirdle, T. J., Krinner, G., Tonelli, M., Haumann, F. A., Naughten, K. A., Rackow, T., Roach, L. A., and Wainer, I.: Twenty first century changes in Antarctic and Southern Ocean surface climate in CMIP6, Atmos. Sci. Lett., 21, e984, https://doi.org/10.1002/asl.984, 2020.
Brady, E., Stevenson, S., Bailey, D., Liu, Z., Noone, D., Nusbaumer, J., Otto-Bliesner, B. L., Tabor, C., Tomas, R., Wong, T., Zhang, J., and Zhu, J.: The connected isotopic water cycle in the Community Earth System Model Version 1, J. Adv. Model. Earth Sy., 11, 2547–2566, https://doi.org/10.1029/2019MS001663, 2019.
Bronnimann, S., Luterbacher, J., Staehelin, J., Svendby, T. M., Hansen, G., Svenoe, T.: Extreme climate of the global troposphere and stratosphere in 1940–42 related to El Niño, Nature, 431, 971–974, https://doi.org/10.1038/nature02982, 2004.
Christian, J. E., Robel, A. A., and Catania, G.: A probabilistic framework for quantifying the role of anthropogenic climate change in marine-terminating glacier retreats, The Cryosphere, 16, 2725–2743, https://doi.org/10.5194/tc-16-2725-2022, 2022.
Christianson, K., Bushuk, M., Dutrieux, P., Parizek, B. R., Joughin, I. R., Alley, R. B., Shean, D. E., Abrahamsen, E. P., Anandakrishnan, S., Heywood, K. J., Kim, T. W., Lee, S. H., Nicholls, K., Stanton, T., Truffer, M., Webber, B. G. M., Jenkins, A., Jacobs, S., Bindschadler, R., and Holland, D. M.: Sensitivity of Pine Island Glacier to observed ocean forcing, Geophys. Res. Lett., 43, 10817–10825, https://doi.org/10.1002/2016gl070500, 2016.
Cobb, K. M.: Coral records of the El Niño-Southern Oscillation and tropical Pacific climate over the last millennium, University of California, 2002.
Dalaiden, Q., Goosse, H., Rezsöhazy, J., and Thomas, E. R.: Reconstructing atmospheric circulation and sea-ice extent in the West Antarctic over the past 200 years using data assimilation, Clim. Dynam., 57, 3479–3503, https://doi.org/10.1007/s00382-021-05879-6, 2021.
Ding, Q. H., Steig, E. J., Battisti, D. S., and Kuttel, M.: Winter warming in West Antarctica caused by central tropical Pacific warming, Nat. Geosci., 4, 398–403, https://doi.org/10.1038/NGEO1129, 2011.
Ding, Q. H., Steig, E. J., Battisti, D. S., and Wallace, J. M.: Influence of the Tropics on the Southern Annular Mode, J. Climate, 25, 6330–6348, 2012.
Dotto, T. S., Naveira Garabato, A. C., Bacon, S., Holland, P. R., Kimura, S., Firing, Y. L., Tsamados, M., Wahlin, A. K., and Jenkins, A.: Wind-driven Processes Controlling Oceanic Heat Delivery to the Amundsen Sea, Antarctica, J. Phys. Oceanogr., 49, 2829–2849, https://doi.org/10.1175/JPO-D-19-0064.1, 2019
Dutrieux, P., De Rydt, J., Jenkins, A., Holland, P. R., Ha, H. K., Lee, S. H., Steig, E. J., Ding, Q. H., Abrahamsen, E. P., and Schroder, M.: Strong Sensitivity of Pine Island Ice-Shelf Melting to Climatic Variability, Science, 343, 174–178, https://doi.org/10.1126/science.1244341, 2014.
ECMWF: Datasets, https://www.ecmwf.int/en/forecasts/datasets (last access: 15 March 2022), 2017.
Flexas, M. M., Thompson, A. F., Schodlok, M. P., Zhang, H., and Speer, K.: Antarctic Peninsula warming triggers enhanced basal melt rates throughout West Antarctica, Sci. Adv., 8, eabj9134, https://doi.org/10.1126/sciadv.abj9134, 2022.
Fogt, R. L., Schneider, D. P., Goergens, C. A., Jones, J. M., Clark, L. N., and Garberoglio, M. J.: Seasonal Antarctic pressure variability during the twentieth century from spatially complete reconstructions and CAM5 simulations, Clim. Dynam., 53, 1435–1452, https://doi.org/10.1007/s00382-019-04674-8, 2019.
Goyal, R., Gupda, A. S., Jucker, M., and England, M. H.: Historical and projected changes in the Southern Hemisphere surface westerlies, Geophys. Res. Lett., 48, e2020GL090849, https://doi.org/10.1029/2020GL090849, 2021.
Hakim, G. J., Emile-Geay, J., Steig, E. J., Noone, D., Anderson, D. M., Tardif, R., Steiger, N., and Perkins, W. A.: The last millennium climate reanalysis project: Framework and first results, J. Geophys. Res.-Atmos., 121, 6745–6764, https://doi.org/10.1002/2016JD024751, 2016.
He, F., Shakun, J. D., Clark, P. U., Carlson, A. E., Liu, Z., Otto-Bliesner, L., and Kutzbach, J. E.: Northern Hemisphere forcing of the Southern Hemisphere climate during the last deglaciation, Nature, 494, 81–85, https://doi.org/10.1038/nature11822, 2013.
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz‐Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R.J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 global reanalysis, Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020.
Holland, P. R., Bracegirdle, T. J., Dutrieux, P., Jenkins, A., and Steig, E. J.: West Antarctic ice loss influenced by internal climate variability and anthropogenic forcing, Nat. Geosci., 12, 718–724, https://doi.org/10.1038/s41561-019-0420-9, 2019.
Holland, P. R., O'Connor, G. K., Bracegirdle, T. J., Dutrieux, P., Naughten, K. A., Steig, E. J., Schneider, D. P., Jenkins, A., and Smith, J. A.: Anthropogenic and internal drivers of wind changes over the Amundsen Sea, West Antarctica, during the 20th and 21st centuries, The Cryosphere, 16, 5085–5105, https://doi.org/10.5194/tc-16-5085-2022, 2022.
Holland, P. R., Bevan, S. L., and Luckman, A. J.: Strong ocean melting feedback during the recent retreat of Thwaites Glacier, Geophys. Res. Lett., 50, e2023GL103088, https://doi.org/10.1029/2023GL103088, 2023.
Jenkins, A., Dutrieux, P., Jacobs, S. S., Steig, E. J., Gudmundsson, G. H., Smith, J., and Heywood, K. J.: Decadal ocean forcing and Antarctic Ice Sheet response: Lessons from the Amundsen Sea, Oceanography, 29, 106–117, https://doi.org/10.5670/oceanog.2016.103, 2016.
Jenkins, A., Shoosmith, D., Dutrieux, P., Jacobs, S., Kim, T. W., Lee, S. H., Ha, H. K., and Stammerhohn, S.: West Antarctic Ice Sheet retreat in the Amundsen Sea driven by decadal oceanic variability, Nat. Geosci., 11, 733–738, https://doi.org/10.1038/s41561-018-0207-4, 2018.
Joughin, I., Smith, B. E., and Medley, B.: Marine Ice Sheet collapse potentially under way for Thwaites Glacier Basin, West Antarctica, Science, 344, 735–738, https://doi.org/10.1126/science.1249055, 2014.
Kay, J. E., Deser, C., Phillips, A., Mai, A., Hannay, C., Strand, G., Arblaster, J. M., Bates, S. C., Danabasoglu, G., Edwards, J., Holland, M., Kushner, P., Lamarque, J. F., Lawrence, D., Lindsay, K., Middleton, A., Munoz, E., Neale, R., Oleson, K., Polvani, L., and Vertenstein, M.: The Community Earth System Model (CESM) Large Ensemble Project: A Community Resource for Studying Climate Change in the Presence of Internal Climate Variability, B. Am. Meteorol. Soc., 96, 1333–1349, https://doi.org/10.1175/Bams-D-13-00255.1, 2015.
Kim, T. W., Ha, H. K., Wahlin, A. K., Lee, S. H., Kim, C. S., Lee, J. H., and Cho, Y. K.: Is Ekamn pumping responsible for the seasonal variation of warm circumpolar deep water in the Amundsen Sea?, Cont. Shelf Res., 132, 38–48, https://doi.org/10.1016/j.csr.2016.09.005, 2017.
Lachlan-Cope, T. and Connolley, W.: Teleconnections between the tropical Pacific and the Amundsen-Bellinghausens sea: Role of the El Niño Southern Oscillation, J. Geophys. Res.-Atmos., 111, D23101, https://doi.org/10.1029/2005jd006386, 2006.
Larter, R. D., Anderson, J. B., Graham, A. G. C., Gohl, K., Hillenbrand, C.-D., Jakobsson, M., Johnson, J. S., Kuhn, G., Nitsche, F., Smith, J. A., Witus, A. E., Bentley, M. J., Dowdeswell, J. A., Ehrmann, W., Klages, J. P., Lindow, J., O Cofaigh, C., and Spiegel, C.: Reconstruction of changes in the Amundsen Sea and Bellingshausen Sea sector of the West Antarctic Ice Sheet since the Last Glacial Maximum, Quaternary Sci. Rev., 100, 55–86, https://doi.org/10.1016/j.quascirev.2013.10.016, 2014.
Li, X., Cai, W., Meehl, G. A., Chen, D., Yuan, X., Raphael, M., Holland, D. M., Ding, Q., Fogt, R. L., Markle, B. R., Wang, G., Bromwich, D. H., Turner, J., Xie, S., Steig, E. J., Gille, S. T., Xiao, C., Wu, B., Lazzara, M. A., Chen, X., Stammerjohn, S., Holland, P. R., Holland, M. M., Cheng, X., Price, S. F., Wang, Z., Bitz, C. M., Shi, J., Gerber, E. P., Liang, X., Goose, H., Yoo, C., Ding, M., Geng, L., Xin, M., Li, C., Dou, T., Liu, C., Sun, W., Wang, X., and Song, C.: Tropical teleconnection impacts on Antarctic climate changes, Nat. Rev. Earth Environ., 2, 680–698, https://doi.org/10.1038/s43017-021-00204-5, 2021.
Mayewski, P. A., Rohling, E. E., Stager, J. C., Karlen, W., Maasch, K. A., Meeker, L. D., Meyerson, E. A., Gasse, F., van Kreveld, S., Holmgren, K., Lee-Thorp, J., Rosqvist, G., Rach, F., Staubwasser, M., Schneider, R. R., and Steig, E. J.: Holocene climate variability, Quat. Res., 62, 3, 243–255, https://doi.org/10.1016/j.yqres.2004.07.001, 2004.
Nakayama, Y., Menemenlis, D., Zhang, H., Schodlok, M., and Rignot, E.: Origin of Circumpolar Deep Water intruding onto the Amundsen and Bellingshausen Sea continental shelves, Nat. Commun., 9, 3403, https://doi.org/10.1038/s41467-018-05813-1, 2018.
Naughten, K. A., Holland, P. R., Dutrieux, P., Kimura, S., Bett, D. T., and Jenkins, A.: Simulated twentieth-century ocean warming in the Amundsen Sea, West Antarctica, Geophys. Res. Lett., 49, e2021GL094566, https://doi.org/10.1029/2021GL094566, 2022.
O'Connor, G. K.: goconnor6/1940_ASE_Analysis: OConnor_2023_tc (v1.0), Zenodo [code], https://doi.org/10.5281/zenodo.10011500, 2023.
O'Connor, G. K., Cobb, K. M., Sayani, H. R., Atwood, A. R., Grothe, P. R., Stevenson, S., Baum, J. K., Chen, T., Claar, D. C., Hitt, N. T., Lynch-Stieglitz, J., Mortlock, R. A., Schmidt, G. A., and Walter, R.: Coral Oxygen Isotopic Records Capture the 2015/2016 El Niño Event in the Central Equatorial Pacific, Geophys. Res. Lett., 48, e2021GL094036, https://doi.org/10.1029/2021GL094036, 2021a.
O'Connor, G. K., Steig, E. J., and Hakim, G. J.: Strengthening Southern Hemisphere westerlies and Amundsen Sea Low deepening over the 20th century revealed by proxy-data assimilation, Geophys. Res. Lett., 48, e2021GL095999, https://doi.org/10.1029/2021GL095999, 2021b.
O'Connor, G. K., Holland, P. R., Steig, E. J., Dutrieux, P., and Hakim, G. J.: 20th century winds, pressure, and temperature around Antarctica from single-proxy data assimilation, Zenodo [data set], https://doi.org/10.5281/zenodo.8007655, 2023.
Okumura, Y. M., Schneider, D., Deser, C., and Wilson, R.: Decadal-interdecadal climate variability over Antarctica and linkages to the tropics: Analysis of ice core, instrumental, and tropical proxy data, J. Climate, 25, 7421–7441, https://doi.org/10.1175/JCLI-D-12-00050.1, 2012.
PAGES2k Consortium: A global multiproxy database for temperature reconstructions of the Common Era, Sci. Data, 4, 170088, https://doi.org/10.1038/sdata.2017.88, 2017.
Perkins, A.: modons/LMR, GitHub [code], https://github.com/modons/LMR, last access: 15 April 2021.
Pritchard, H. D., Ligtenberg, S. R. M., Fricker, H. A., Vaughn, D. G., van den Broeke, M. R., and Padman, L.: Antarctic ice-sheet loss driven by basal melting of ice shelves, Nature, 484, 502–505, https://doi.org/10.1038/nature10968, 2012.
Sanchez, S. C., Westphal, N., Haug, G. H., Cheng, H., Edwards, R. L., Schneider, T., Cobb, K. M., and Charles, C. D.: A Continuous Record of Central Tropical Pacific Climate Since the Midnineteenth Century Reconstructed From Fanning and Palmyra Island Corals: A Case Study in Coral Data Reanalysis, Paleoceanogr. Paleocl., 35, e2020PA003848, https://doi.org/10.1029/2020PA003848, 2020.
Sanchez, S. C., Hakim, G. J., and Saenger, C. P.: Climate model teleconnection patterns govern the Niño 3.4 response to early 19th century volcanism in coral-based data assimilation reconstructions, J. Climate, 34, 1863–1880, https://doi.org/10.1175/JCLI-D-20-0549.1, 2021.
Schneider, D. P. and Deser, C.: Tropically driven and externally forced patterns of Antarctic sea ice change: reconciling observed and modeled trends, Clim. Dynam., 50, 4599–4618, https://doi.org/10.1007/s00382-017-3893-5, 2018.
Schneider, D. P. and Steig, E. J.: Ice cores record significant 1940s Antarctic warmth related to tropical climate variability, P. Natl. Acad. Sci. USA, 105, 12154–12158, https://doi.org/10.1073/pnas.0803627105, 2008.
Shepherd, A., Wingham, D., and Mansley, J. A.: Inland thinning of the Amundsen Sea sector, West Antarctica, Geophys. Res. Lett., 29, 1364, https://doi.org/10.1029/2001GL014183, 2002.
Shepherd, A., Gilbert, L., Muir, A. S., Konrad, H., McMillan, M., Slater, T., Briggs, K. H., Sundal, A. V., Hogg, A. E., and Engdahl, M. E.: Trends in Antarctic Ice Sheet Elevation and Mass, Geophys. Res. Lett., 46, 8174–8183, https://doi.org/10.1029/2019gl082182, 2019.
Silvano, A., Holland, P. R., Naughten, K. A., Dragomir, O., Dutrieux, P., Jenkins, A., Si, Y., Stewart, A. L., Peña Molino, B., Janzing, G. W., Dotto, T. S., and Naveira Garabato, A. C.: Baroclinic ocean response to climate forcing regulates decadal variability of ice-shelf melting in the Amundsen Sea, Geophys. Res. Lett., 49, e2022GL100646, https://doi.org/10.1029/2022GL100646, 2022.
Slivinski, L. C., Compo, G. P., Whitaker, J. S., Sardeshmukh, P. D., Giese, B. S., McColl, C., Allan, R., Yin, X., Vose, R., Titchner, H., Kennedy, J., Spencer, L.J., Ashcroft, L., Brönnimann, S., Brunet, M., Camuffo, D., Cornes, R., Cram, T.A., Crouthamel, R., Domínguez-Castro, F., Freeman, J. E., Gergis, J., Hawkins, E., Jones, P.D., Jourdain, S., Kaplan, A., Kubota, H., Blancq, F. L., Lee, T., Lorrey, A., Luterbacher, J., Maugeri, M., Mock, C. J., Moore, G. W. K., Przybylak, R., Pudmenzky, C., Reason, C., Slonosky, V. C., Smith, C. A., Tinz, B., Trewin, B., Valente, M. A., Wang, X. L., Wilkinson, C., Wood, K., and Wyszyński, P.: Towards a more reliable historical reanalysis: Improvements for version 3 of the Twentieth Century Reanalysis system, Q. J. Roy. Meteor. Soc., 145, 2876–2908, https://doi.org/10.1002/qj.3598, 2019.
Smith, B., Fricker, H. A., Gardner, A. S., Medley, B., Nilsson, J., Paolo Nicholas Holschuh, F. S., Adusumilli, S., Brunt, K., Csatho, B., Harbeck, K., Markus, T., Neumann, T., Siegfried, M. R., and Jay Zwally, H.: Pervasive ice sheet mass loss reflects competing ocean and atmosphere processes, Science, 368, 1239–1242, 10.1126/science.aaz5845, 2020.
Smith, J. A., Andersen, T. J., Shortt, M., Gaffney, A. M., Truffer, M., Stanton, T. P., Bindschadler, R., Dutrieux, P., Jenkins, A., Hillenbrand, C. D., Ehrmann, W., Corr, H. F. J., Farley, N., Crowhurst, S., and Vaughan, D. G.: Sub-ice-shelf sediments record history of twentieth-century retreat of Pine Island Glacier, Nature, 549, 292–292, https://doi.org/10.1038/nature23650, 2017.
Stammerjohn, S., Maksym, T., Massom, R. A., Lowry, K. E., Arrigo, K. R., Yu, X., Raphael, M., Randall-Goodwin, E., Sherrell, R. M., and Yager, P. L.: Seasonal sea ice changes in the Amundsen Sea, Antarctica, over the period of 1979–2014, Elementa, 3, 000055, https://doi.org/10.12952/journal.elementa.000055, 2015.
Steig, E. J., Mayewski, P. A., Dixon, D., Kaspari, S, Frey, M., Schneider, D., Arcone, S., Hamilton, G., Spikes, V., Albert, M., Mess, D., Gow, A., Shuman, C. White, J. W. C., Sneed, S., Flaherty, J., and Wumkes, M.: High-resolution Ice Cores from US ITASE (West Antarctica): development and validation of chronologies and determination of precision and accuracy, Ann. Glaciol., 41, 77–84, https://doi.org/10.3189/172756405781813311, 2005.
Steig, E. J., Ding, Q., Battisti, D. S., and Jenkins, A.: Tropical forcing of Circumpolar Deep Water Inflow and outlet glacier thinning in the Amundsen Sea Embayment, West Antarctica, Ann. Glaciol., 53, 19–28, https://doi.org/10.3189/2012AoG60A110, 2012.
Steig, E. J., Ding, Q. H., White, J. W. C., Kuttel, M., Rupper, S. B., Neumann, T. A., Neff, P. D., Gallant, A. J. E., Mayewski, P. A., Taylor, K. C., Hoffmann, G., Dixon, D. A., Schoenemann, S. W., Markle, B. R., Fudge, T. J., Schneider, D. P., Schauer, A. J., Teel, R. P., Vaughn, B. H., Burgener, L., Williams, J., and Korotkikh, E.: Recent climate and ice-sheet changes in West Antarctica compared with the past 2,000 years, Nat. Geosci., 6, 372–375, https://doi.org/10.1038/Ngeo1778, 2013.
Thoma, M., Jenkins, A., Holland, D., and Jacobs, S.: Modelling Circumpolar Deep Water intrusions on the Amundsen Sea continental shelf, Antarctica, Geophys. Res. Lett., 35, L18602, https://doi.org/10.1029/2008gl034939, 2008.
Thomas, E. R., van Wessem, J. M., Roberts, J., Isaksson, E., Schlosser, E., Fudge, T. J., Vallelonga, P., Medley, B., Lenaerts, J., Bertler, N., van den Broeke, M. R., Dixon, D. A., Frezzotti, M., Stenni, B., Curran, M., and Ekaykin, A. A.: Regional Antarctic snow accumulation over the past 1000 years, Clim. Past, 13, 1491–1513, https://doi.org/10.5194/cp-13-1491-2017, 2017.
Thompson, D. W. J., Solomon, S., Kushner, P. J., England, M. H., Grise, K. M., and Karoly, D. J.: Signatures of the Antarctic ozone hole in Southern Hemisphere surface climate change, Nat. Geosci., 4, 741–749, https://doi.org/10.1038/Ngeo1296, 2011.
Wåhlin, A. K., Kalen, O., Arneborg, L., Bjork, G., Carvajal, G. K., Ha, H. K., Kim, T. W., Lee, S. H., Lee, J. H., and Stranne, C.: Variability of Warm Deep Water Inflow in a Submarine Trough on the Amundsen Sea Shelf, J. Phys. Oceanogr., 43, 2054–2079, 2013.
Wåhlin, A. K., Graham, A. G. C., Hogan, K. A., Queste, B. Y., Boehme, L., Larter, R. D., Pettit, E. C., Wellner, J., and Heywood, K. J.: Pathways and modification of warm water flowing beneath Thwaites Ice Shelf, West Antarctica, Sci. Adv., 7, eabd7254, https://doi.org/10.1175/JPO-D-12-0157.1, 2021.
Walker, D. P., Jenkins, A. Assmann, K. M., Shoosmith, D. R., and Brandon, M. A.: Oceanographic observations at the shelf break of the Amundsen Sea, Antarctica, J. Geophys. Res.-Oceans, 118, 2906–2918, https://doi.org/10.1002/jgrc.20212, 2013.
Webber, B. G. M., Heywood, K. J., Stevens, D. P., and Assmann, K. M.: The Impact of Overturning and Horizontal Circulation in Pine Island Trough on Ice Shelf Melt in the Eastern Amundsen Sea, J. Phys. Oceanogr., 49, 63–83, https://doi.org/10.1175/JPO-D-17-0213.1, 2019.
Wohland, J., Omrani, N. E., Witthaut, D., and Keenlyside, N. S.: Inconsistent wind speed trends in current twentieth century reanalyses, J. Geophys. Res.-Atmos., 124, 1931–1940, https://doi.org/10.1029/2018JD030083, 2019.
Yager, P. L., Sherrell, R. M., Stammerjohn, S. E., Ducklow, H. W., Schofield, O. M. E., Ingall, E. D., Wilson, S. E., Lowry, K. E., Williams, C. M., Riemann, L., Bertilsson, S., Alderkamp, A. C., Dinasquet, J., Logares, R., Richert, I., Sipler, R. E., Melara, A. J., Mu, L., Newstead, R. G., Post, A. F., Swalethorp, R., and van Dijken, G. L.: A carbon budget for the Amundsen Sea Polynya, Antarctica: Estimating net community production and export in a highly productive polar ecosystem, Elementa, 4, 000140, https://doi.org/10.12952/journal.elementa.000140, 2016.
Yang, D., Arblaster, J. M., Meehl, G. A., England, M. H., Lim, E.-P., Bates, S., and Rosenbloom, N.: Role of tropical variability in driving decadal shifts in the Southern Hemisphere summertime eddy-driven jet, J. Climate, 33, 5445–5463, https://doi.org/10.1175/JCLI-D-19-0604.1, 2020.
Short summary
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.
Glaciers in West Antarctica are rapidly melting, but the causes are unknown due to limited...