Sensitivity of the West Antarctic Ice Sheet to +2 °C (SWAIS 2C)
Molly O. Patterson
CORRESPONDING AUTHOR
Department of Geological Sciences and Environmental Studies, Binghamton University, Binghamton, NY, USA
Richard H. Levy
GNS Science, Lower Hutt, New Zealand
Antarctic Research Centre, Victoria University of Wellington,
Wellington, New Zealand
Denise K. Kulhanek
Department of Geological Sciences and Environmental Studies, Binghamton University, Binghamton, NY, USA
Institute of Geosciences, Christian-Albrecht University of Kiel, Kiel, Germany
Tina van de Flierdt
Department of Earth Science and Engineering, Imperial College London, London, UK
Huw Horgan
Antarctic Research Centre, Victoria University of Wellington,
Wellington, New Zealand
Gavin B. Dunbar
Antarctic Research Centre, Victoria University of Wellington,
Wellington, New Zealand
Timothy R. Naish
Antarctic Research Centre, Victoria University of Wellington,
Wellington, New Zealand
Jeanine Ash
Department of Earth, Environmental and Planetary Sciences, Rice
University, Houston, TX, USA
Alex Pyne
Antarctic Research Centre, Victoria University of Wellington,
Wellington, New Zealand
Darcy Mandeno
Antarctic Research Centre, Victoria University of Wellington,
Wellington, New Zealand
Paul Winberry
Department of Geological Sciences, Central Washington University,
Ellensburg, WA, USA
David M. Harwood
Department of Earth & Atmospheric Sciences, University of
Nebraska-Lincoln, Lincoln, NE, USA
Fabio Florindo
Instituto Nazionale di Geofisica e Vulcanologia, Rome, Italy
Francisco J. Jimenez-Espejo
Instituto Andaluz de Ciencias de la Tierra, Spanish Research Council (CSIC), Armilla, Spain
Andreas Läufer
Federal Institute for Geosciences and Natural Resources (BGR),
Hannover, Germany
Kyu-Cheul Yoo
Division of Glacial Environment Research, Korea Polar Research
Institute, Incheon, Republic of Korea
Osamu Seki
National Institute of Polar Research, 10-3 Midori-cho, Tachikawa,
Tokyo, Japan
Institute of Low Temperature Science, Hokkaidō University,
Sapporo, Japan
Paolo Stocchi
Department of Coastal Systems, NIOZ Royal Netherlands Institute for Sea Research, Den Burg, the Netherlands
Johann P. Klages
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine
Research, Bremerhaven, Germany
Jae Il Lee
Division of Glacial Environment Research, Korea Polar Research
Institute, Incheon, Republic of Korea
Florence Colleoni
Istituto Nazionale di Oceanografia e Geofisica Sperimentale, Trieste, Italy
Yusuke Suganuma
National Institute of Polar Research, 10-3 Midori-cho, Tachikawa,
Tokyo, Japan
Edward Gasson
School of Geographical Sciences, University of Bristol, Bristol, UK
Christian Ohneiser
Department of Geology, University of Otago, Dunedin, New Zealand
José-Abel Flores
Department of Geology, University of Salamanca, Salamanca, Spain
David Try
GNS Science, Lower Hutt, New Zealand
Rachel Kirkman
GNS Science, Lower Hutt, New Zealand
Daleen Koch
GNS Science, Lower Hutt, New Zealand
A full list of authors appears at the end of the paper.
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Despite its importance in the global climate, our knowledge of Antarctic sea-ice changes throughout the last glacial–interglacial cycle is extremely limited. As part of the Cycles of Sea Ice Dynamics in the Earth system (C-SIDE) Working Group, we review marine- and ice-core-based sea-ice proxies to provide insights into their applicability and limitations. By compiling published records, we provide information on Antarctic sea-ice dynamics over the past 130 000 years.
Astrid Oetting, Emma C. Smith, Jan Erik Arndt, Boris Dorschel, Reinhard Drews, Todd A. Ehlers, Christoph Gaedicke, Coen Hofstede, Johann P. Klages, Gerhard Kuhn, Astrid Lambrecht, Andreas Läufer, Christoph Mayer, Ralf Tiedemann, Frank Wilhelms, and Olaf Eisen
The Cryosphere, 16, 2051–2066, https://doi.org/10.5194/tc-16-2051-2022, https://doi.org/10.5194/tc-16-2051-2022, 2022
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This study combines a variety of geophysical measurements in front of and beneath the Ekström Ice Shelf in order to identify and interpret geomorphological evidences of past ice sheet flow, extent and retreat.
The maximal extent of grounded ice in this region was 11 km away from the continental shelf break.
The thickness of palaeo-ice on the calving front around the LGM was estimated to be at least 305 to 320 m.
We provide essential boundary conditions for palaeo-ice-sheet models.
Lennert B. Stap, Constantijn J. Berends, Meike D. W. Scherrenberg, Roderik S. W. van de Wal, and Edward G. W. Gasson
The Cryosphere, 16, 1315–1332, https://doi.org/10.5194/tc-16-1315-2022, https://doi.org/10.5194/tc-16-1315-2022, 2022
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To gain understanding of how the Antarctic ice sheet responded to CO2 changes during past warm climate conditions, we simulate its variability during the Miocene. We include feedbacks between the ice sheet and atmosphere in our model and force the model using time-varying climate conditions. We find that these feedbacks reduce the amplitude of ice volume variations. Erosion-induced changes in the bedrock below the ice sheet that manifested during the Miocene also have a damping effect.
Jacob Jones, Karen E. Kohfeld, Helen Bostock, Xavier Crosta, Melanie Liston, Gavin Dunbar, Zanna Chase, Amy Leventer, Harris Anderson, and Geraldine Jacobsen
Clim. Past, 18, 465–483, https://doi.org/10.5194/cp-18-465-2022, https://doi.org/10.5194/cp-18-465-2022, 2022
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We provide new winter sea ice and summer sea surface temperature estimates for marine core TAN1302-96 (59° S, 157° E) in the Southern Ocean. We find that sea ice was not consolidated over the core site until ~65 ka and therefore believe that sea ice may not have been a major contributor to early glacial CO2 drawdown. Sea ice does appear to have coincided with Antarctic Intermediate Water production and subduction, suggesting it may have influenced intermediate ocean circulation changes.
Jamey Stutz, Andrew Mackintosh, Kevin Norton, Ross Whitmore, Carlo Baroni, Stewart S. R. Jamieson, Richard S. Jones, Greg Balco, Maria Cristina Salvatore, Stefano Casale, Jae Il Lee, Yeong Bae Seong, Robert McKay, Lauren J. Vargo, Daniel Lowry, Perry Spector, Marcus Christl, Susan Ivy Ochs, Luigia Di Nicola, Maria Iarossi, Finlay Stuart, and Tom Woodruff
The Cryosphere, 15, 5447–5471, https://doi.org/10.5194/tc-15-5447-2021, https://doi.org/10.5194/tc-15-5447-2021, 2021
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Understanding the long-term behaviour of ice sheets is essential to projecting future changes due to climate change. In this study, we use rocks deposited along the margin of the David Glacier, one of the largest glacier systems in the world, to reveal a rapid thinning event initiated over 7000 years ago and endured for ~ 2000 years. Using physical models, we show that subglacial topography and ocean heat are important drivers for change along this sector of the Antarctic Ice Sheet.
Fabrizio Marra, Alison Pereira, Brian Jicha, Sebastien Nomade, Italo Biddittu, Fabio Florindo, Giovanni Muttoni, Elizabeth Niespolo, Paul Renne, and Vincent Scao
Clim. Past Discuss., https://doi.org/10.5194/cp-2021-161, https://doi.org/10.5194/cp-2021-161, 2021
Publication in CP not foreseen
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We demonstrate that coarse gravel deposition in the catchment basins of the major rivers of central Italy is a direct proxy of global deglaciation events associated with meltwater pulses. By precise 40Ar/39Ar dating of the sedimentary deposits we show that emplacement of these gravel beds is closely coincident with discrete events of sea-level rise, with peaks of the Ice-rafted debris (IRD) curve, and with particularly mild (warmer) minima of mean summer insolation at 65° N.
Karla Rubio-Sandoval, Alessio Rovere, Ciro Cerrone, Paolo Stocchi, Thomas Lorscheid, Thomas Felis, Ann-Kathrin Petersen, and Deirdre D. Ryan
Earth Syst. Sci. Data, 13, 4819–4845, https://doi.org/10.5194/essd-13-4819-2021, https://doi.org/10.5194/essd-13-4819-2021, 2021
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The Last Interglacial (LIG) is a warm period characterized by a higher-than-present sea level. For this reason, scientists use it as an analog for future climatic conditions. In this paper, we use the World Atlas of Last Interglacial Shorelines database to standardize LIG sea-level data along the coasts of the western Atlantic and mainland Caribbean, identifying 55 unique sea-level indicators.
Florence Colleoni, Laura De Santis, Enrico Pochini, Edy Forlin, Riccardo Geletti, Giuseppe Brancatelli, Magdala Tesauro, Martina Busetti, and Carla Braitenberg
Geosci. Model Dev., 14, 5285–5305, https://doi.org/10.5194/gmd-14-5285-2021, https://doi.org/10.5194/gmd-14-5285-2021, 2021
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PALEOSTRIP has been developed in the framework of past Antarctic ice sheet reconstructions for periods when bathymetry around Antarctica differed substantially from today. It has been designed for users with no knowledge of numerical modelling and allows users to switch on and off the processes involved in backtracking and backstripping. Applications are broad, and it can be used to restore any continental margin bathymetry or sediment thickness and to perform basin analysis.
Deirdre D. Ryan, Alastair J. H. Clement, Nathan R. Jankowski, and Paolo Stocchi
Earth Syst. Sci. Data, 13, 3399–3437, https://doi.org/10.5194/essd-13-3399-2021, https://doi.org/10.5194/essd-13-3399-2021, 2021
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Studies of ancient sea level and coastlines help scientists understand how coasts will respond to future sea-level rise. This work standardized the published records of sea level around New Zealand correlated with sea-level peaks within the Last Interglacial (~128 000–73 000 years ago) using the World Atlas of Last Interglacial Shorelines (WALIS) database. New Zealand has the potential to provide an important sea-level record with more detailed descriptions and improved age constraint.
Jens O. Herrle, Cornelia Spiegel, Andreas Läufer, and Jean-Pierre Paul de Vera
Polarforschung, 89, 51–55, https://doi.org/10.5194/polf-89-51-2021, https://doi.org/10.5194/polf-89-51-2021, 2021
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The Geology and Geophysics working group is one the largest within the German Society of Polar Research. Here, we present an overview of the development of major scientific German polar research programs and locations as well as important white papers from the last decades. This work is based on the contributions of members and institutions, including the Alfred Wegener Institute, the Federal Institute for Geosciences and Natural Resources and German Universities with polar research programs.
Huw J. Horgan, Laurine van Haastrecht, Richard B. Alley, Sridhar Anandakrishnan, Lucas H. Beem, Knut Christianson, Atsuhiro Muto, and Matthew R. Siegfried
The Cryosphere, 15, 1863–1880, https://doi.org/10.5194/tc-15-1863-2021, https://doi.org/10.5194/tc-15-1863-2021, 2021
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The grounding zone marks the transition from a grounded ice sheet to a floating ice shelf. Like Earth's coastlines, the grounding zone is home to interactions between the ocean, fresh water, and geology but also has added complexity and importance due to the overriding ice. Here we use seismic surveying – sending sound waves down through the ice – to image the grounding zone of Whillans Ice Stream in West Antarctica and learn more about the nature of this important transition zone.
Romana Melis, Lucilla Capotondi, Fiorenza Torricella, Patrizia Ferretti, Andrea Geniram, Jong Kuk Hong, Gerhard Kuhn, Boo-Keun Khim, Sookwan Kim, Elisa Malinverno, Kyu Cheul Yoo, and Ester Colizza
J. Micropalaeontol., 40, 15–35, https://doi.org/10.5194/jm-40-15-2021, https://doi.org/10.5194/jm-40-15-2021, 2021
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Integrated micropaleontological (planktic and benthic foraminifera, diatoms, and silicoflagellates) analysis, together with textural and geochemical results of a deep-sea core from the Hallett Ridge (northwestern Ross Sea), provides new data for late Quaternary (23–2 ka) paleoenvironmental and paleoceanographic reconstructions of this region. Results allow us to identify three time intervals: the glacial–deglacial transition, the deglacial period, and the interglacial period.
Kate E. Ashley, Robert McKay, Johan Etourneau, Francisco J. Jimenez-Espejo, Alan Condron, Anna Albot, Xavier Crosta, Christina Riesselman, Osamu Seki, Guillaume Massé, Nicholas R. Golledge, Edward Gasson, Daniel P. Lowry, Nicholas E. Barrand, Katelyn Johnson, Nancy Bertler, Carlota Escutia, Robert Dunbar, and James A. Bendle
Clim. Past, 17, 1–19, https://doi.org/10.5194/cp-17-1-2021, https://doi.org/10.5194/cp-17-1-2021, 2021
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We present a multi-proxy record of Holocene glacial meltwater input, sediment transport, and sea-ice variability off East Antarctica. Our record shows that a rapid Antarctic sea-ice increase during the mid-Holocene (~ 4.5 ka) occurred against a backdrop of increasing glacial meltwater input and gradual climate warming. We suggest that mid-Holocene ice shelf cavity expansion led to cooling of surface waters and sea-ice growth, which slowed basal ice shelf melting.
Wei Ji Leong and Huw Joseph Horgan
The Cryosphere, 14, 3687–3705, https://doi.org/10.5194/tc-14-3687-2020, https://doi.org/10.5194/tc-14-3687-2020, 2020
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A machine learning technique similar to the one used to enhance everyday photographs is applied to the problem of getting a better picture of Antarctica's bed – the part which is hidden beneath the ice. By taking hints from what satellites can observe at the ice surface, the novel method learns to generate a rougher bed topography that complements existing approaches, with a result that is able to be used by scientists running fine-scale ice sheet models relevant to predicting future sea levels.
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Short summary
How much of the West Antarctic Ice Sheet will melt and how quickly it will happen when average global temperatures exceed 2 °C is currently unknown. Given the far-reaching and international consequences of Antarctica’s future contribution to global sea level rise, the SWAIS 2C Project was developed in order to better forecast the size and timing of future changes.
How much of the West Antarctic Ice Sheet will melt and how quickly it will happen when average...