Articles | Volume 5, issue 3
Research article 18 Jul 2011
Research article | 18 Jul 2011
Getting around Antarctica: new high-resolution mappings of the grounded and freely-floating boundaries of the Antarctic ice sheet created for the International Polar Year
R. Bindschadler et al.
Related subject area
AntarcticSensitivity of the Antarctic ice sheets to the warming of marine isotope substage 11cAirborne mapping of the sub-ice platelet layer under fast ice in McMurdo Sound, AntarcticaExploring the impact of atmospheric forcing and basal drag on the Antarctic Ice Sheet under Last Glacial Maximum conditionsSpectral characterization, radiative forcing and pigment content of coastal Antarctic snow algae: approaches to spectrally discriminate red and green communities and their impact on snowmeltDrivers of Pine Island Glacier speed-up between 1996 and 2016Evaluation of sea-ice thickness from four reanalyses in the Antarctic Weddell SeaScoring Antarctic surface mass balance in climate models to refine future projectionsThe Antarctic sea ice cover from ICESat-2 and CryoSat-2: freeboard, snow depth, and ice thicknessDistinguishing the impacts of ozone and ozone-depleting substances on the recent increase in Antarctic surface mass balanceDistribution and seasonal evolution of supraglacial lakes on Shackleton Ice Shelf, East AntarcticaRepresentative surface snow density on the East Antarctic PlateauMapping the grounding zone of Larsen C Ice Shelf, Antarctica, from ICESat-2 laser altimetryDiverging future surface mass balance between the Antarctic ice shelves and grounded ice sheetImpact of coastal East Antarctic ice rises on surface mass balance: insights from observations and modelingTemporal and spatial variability in surface roughness and accumulation rate around 88° S from repeat airborne geophysical surveysThe role of history and strength of the oceanic forcing in sea level projections from Antarctica with the Parallel Ice Sheet ModelISMIP6 Antarctica: a multi-model ensemble of the Antarctic ice sheet evolution over the 21st centuryNew gravity-derived bathymetry for the Thwaites, Crosson, and Dotson ice shelves revealing two ice shelf populationsRevealing the former bed of Thwaites Glacier using sea-floor bathymetry: implications for warm-water routing and bed controls on ice flow and buttressingSeasonal and interannual variability of landfast sea ice in Atka Bay, Weddell Sea, AntarcticaBrief communication: Evaluating Antarctic precipitation in ERA5 and CMIP6 against CloudSat observationsA 14.5-million-year record of East Antarctic Ice Sheet fluctuations from the central Transantarctic Mountains, constrained with cosmogenic 3He, 10Be, 21Ne, and 26AlExperimental protocol for sea level projections from ISMIP6 stand-alone ice sheet modelsPhysics-based modeling of Antarctic snow and firn densityRecent acceleration of Denman Glacier (1972–2017), East Antarctica, driven by grounding line retreat and changes in ice tongue configurationFuture ice-sheet surface mass balance and melting in the Amundsen region, West AntarcticaLarge-scale englacial folding and deep-ice stratigraphy within the West Antarctic Ice SheetThe GRISLI-LSCE contribution to ISMIP6, Part 2: projections of the Antarctic ice sheet evolution by the end of the 21st centuryDrifting-snow statistics from multiple-year autonomous measurements in Adélie Land, East AntarcticaSynoptic conditions and atmospheric moisture pathways associated with virga and precipitation over coastal Adélie Land in AntarcticaRefractory black carbon (rBC) variability in a 47-year West Antarctic snow and firn coreSpatial probabilistic calibration of a high-resolution Amundsen Sea Embayment ice sheet model with satellite altimeter dataHow useful is snow accumulation in reconstructing surface air temperature in Antarctica? A study combining ice core records and climate modelsDetailed detection of active layer freeze–thaw dynamics using quasi-continuous electrical resistivity tomography (Deception Island, Antarctica)Solar radiative transfer in Antarctic blue ice: spectral considerations, subsurface enhancement, inclusions, and meteoritesGlacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 1: Boundary conditions and climatic forcingGlacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) – Part 2: Parameter ensemble analysisPan-Antarctic map of near-surface permafrost temperatures at 1 km2 scaleInfluence of sea-ice anomalies on Antarctic precipitation using source attribution in the Community Earth System ModelWhat is the Surface Mass Balance of Antarctica? An Intercomparison of Regional Climate Model EstimatesInterannual variability of summer surface mass balance and surface melting in the Amundsen sector, West AntarcticaImpact of exhaust emissions on chemical snowpack composition at Concordia Station, AntarcticaISMIP6 projections of ocean-forced Antarctic Ice Sheet evolution using the Community Ice Sheet ModelThickness of the divide and flank of the West Antarctic Ice Sheet through the last deglaciationNew Last Glacial Maximum ice thickness constraints for the Weddell Sea Embayment, AntarcticaCalving cycle of the Brunt Ice Shelf, Antarctica, driven by changes in ice shelf geometryBrief communication: A submarine wall protecting the Amundsen Sea intensifies melting of neighboring ice shelvesModelling the Antarctic Ice Sheet across the mid-Pleistocene transition – implications for Oldest IceObservation of the process of snow accumulation on the Antarctic Plateau by time lapse laser scanningPast water flow beneath Pine Island and Thwaites glaciers, West Antarctica
Martim Mas e Braga, Jorge Bernales, Matthias Prange, Arjen P. Stroeven, and Irina Rogozhina
The Cryosphere, 15, 459–478,Short summary
We combine a computer model with different climate records to simulate how Antarctica responded to warming during marine isotope substage 11c, which can help understand Antarctica's natural drivers of change. We found that the regional climate warming of Antarctica seen in ice cores was necessary for the model to match the recorded sea level rise. A collapse of its western ice sheet is possible if a modest warming is sustained for ca. 4000 years, contributing 6.7 to 8.2 m to sea level rise.
Christian Haas, Patricia J. Langhorne, Wolfgang Rack, Greg H. Leonard, Gemma M. Brett, Daniel Price, Justin F. Beckers, and Alex J. Gough
The Cryosphere, 15, 247–264,Short summary
We developed a method to remotely detect proxy signals of Antarctic ice shelf melt under adjacent sea ice. It is based on aircraft surveys with electromagnetic induction sounding. We found year-to-year variability of the ice shelf melt proxy in McMurdo Sound and spatial fine structure that support assumptions about the melt of the McMurdo Ice Shelf. With this method it will be possible to map and detect locations of intense ice shelf melt along the coast of Antarctica.
Javier Blasco, Jorge Alvarez-Solas, Alexander Robinson, and Marisa Montoya
The Cryosphere, 15, 215–231,Short summary
During the Last Glacial Maximum the Antarctic Ice Sheet was larger and more extended than at present. However, neither its exact position nor the total ice volume are well constrained. Here we investigate how the different climatic boundary conditions, as well as basal friction configurations, affect the size and extent of the Antarctic Ice Sheet and discuss its potential implications.
Alia L. Khan, Heidi M. Dierssen, Ted A. Scambos, Juan Höfer, and Raul R. Cordero
The Cryosphere, 15, 133–148,Short summary
We present radiative forcing (RF) estimates by snow algae in the Antarctic Peninsula (AP) region from multi-year measurements of solar radiation and ground-based hyperspectral characterization of red and green snow algae collected during a brief field expedition in austral summer 2018. Mean daily RF was double for green (~26 W m−2) vs. red (~13 W m−2) snow algae during the peak growing season, which is on par with midlatitude dust attributions capable of advancing snowmelt.
Jan De Rydt, Ronja Reese, Fernando S. Paolo, and G. Hilmar Gudmundsson
The Cryosphere, 15, 113–132,Short summary
We used satellite observations and numerical simulations of Pine Island Glacier, West Antarctica, between 1996 and 2016 to show that the recent increase in its flow speed can only be reproduced by computer models if stringent assumptions are made about the material properties of the ice and its underlying bed. These assumptions are not commonly adopted in ice flow modelling, and our results therefore have implications for future simulations of Antarctic ice flow and sea level projections.
Qian Shi, Qinghua Yang, Longjiang Mu, Jinfei Wang, François Massonnet, and Matthew R. Mazloff
The Cryosphere, 15, 31–47,Short summary
The ice thickness from four state-of-the-art reanalyses (GECCO2, SOSE, NEMO-EnKF and GIOMAS) are evaluated against that from remote sensing and in situ observations in the Weddell Sea, Antarctica. Most of the reanalyses can reproduce ice thickness in the central and eastern Weddell Sea but failed to capture the thick and deformed ice in the western Weddell Sea. These results demonstrate the possibilities and limitations of using current sea-ice reanalysis in Antarctic climate research.
Tessa Gorte, Jan T. M. Lenaerts, and Brooke Medley
The Cryosphere, 14, 4719–4733,Short summary
In this paper, we analyze several spatial and temporal criteria to assess the ability of models in the CMIP5 and CMIP6 frameworks to recreate past Antarctic surface mass balance. We then compared a subset of the top performing models to all remaining models to refine future surface mass balance predictions under different forcing scenarios. We found that the top performing models predict lower surface mass balance by 2100, indicating less buffering than otherwise expected of sea level rise.
Sahra Kacimi and Ron Kwok
The Cryosphere, 14, 4453–4474,Short summary
Our current understanding of Antarctic ice cover is largely informed by ice extent measurements from passive microwave sensors. These records, while useful, provide a limited picture of how the ice is responding to climate change. In this paper, we combine measurements from ICESat-2 and CryoSat-2 missions to assess snow depth and ice thickness of the Antarctic ice cover over an 8-month period (April through November 2019). The potential impact of salinity in the snow layer is discussed.
Rei Chemke, Michael Previdi, Mark R. England, and Lorenzo M. Polvani
The Cryosphere, 14, 4135–4144,Short summary
The increase in Antarctic surface mass balance (SMB, precipitation vs. evaporation/sublimation) is projected to mitigate sea-level rise. Here we show that nearly half of this increase over the 20th century is attributed to stratospheric ozone depletion and ozone-depleting substance (ODS) emissions. Our results suggest that the phaseout of ODS by the Montreal Protocol, and the recovery of stratospheric ozone, will act to decrease the SMB over the 21st century and the mitigation of sea-level rise.
Jennifer F. Arthur, Chris R. Stokes, Stewart S. R. Jamieson, J. Rachel Carr, and Amber A. Leeson
The Cryosphere, 14, 4103–4120,Short summary
Surface meltwater lakes can flex and fracture ice shelves, potentially leading to ice shelf break-up. A long-term record of lake evolution on Shackleton Ice Shelf is produced using optical satellite imagery and compared to surface air temperature and modelled surface melt. The results reveal that lake clustering on the ice shelf is linked to melt-enhancing feedbacks. Peaks in total lake area and volume closely correspond with intense snowmelt events rather than with warmer seasonal temperatures.
Alexander H. Weinhart, Johannes Freitag, Maria Hörhold, Sepp Kipfstuhl, and Olaf Eisen
The Cryosphere, 14, 3663–3685,Short summary
From 1 m snow profiles along a traverse on the East Antarctic Plateau, we calculated a representative surface snow density of 355 kg m−3 for this region with an error less than 1.5 %. This density is 10 % higher and density fluctuations seem to happen on smaller scales than climate model outputs suggest. Our study can help improve the parameterization of surface snow density in climate models to reduce the error in future sea level predictions.
Tian Li, Geoffrey J. Dawson, Stephen J. Chuter, and Jonathan L. Bamber
The Cryosphere, 14, 3629–3643,Short summary
Accurate knowledge of the Antarctic grounding zone is critical for the understanding of ice sheet instability and the evaluation of mass balance. We present a new, fully automated method to map the grounding zone from ICESat-2 laser altimetry. Our results of Larsen C Ice Shelf demonstrate the efficiency, density, and high spatial accuracy with which ICESat-2 can image complex grounding zones.
Christoph Kittel, Charles Amory, Cécile Agosta, Nicolas C. Jourdain, Stefan Hofer, Alison Delhasse, Sébastien Doutreloup, Pierre-Vincent Huot, Charlotte Lang, Thierry Fichefet, and Xavier Fettweis
The Cryosphere Discuss.,
Revised manuscript accepted for TCShort summary
The future surface mass balance (SMB) of the Antarctic ice sheet (AIS) will influence the ice dynamics and the contribution of the ice sheet to the sea-level rise. We investigate the AIS sensitivity to different warmings using physical and statistical downscallings of CMIP5 and CMIP6 models. Our results highlight a contrasting effect between the grounded ice sheet (where the SMB is projected to increase) and ice shelves (where the future SMB depends on the emission scenario).
Thore Kausch, Stef Lhermitte, Jan T. M. Lenaerts, Nander Wever, Mana Inoue, Frank Pattyn, Sainan Sun, Sarah Wauthy, Jean-Louis Tison, and Willem Jan van de Berg
The Cryosphere, 14, 3367–3380,Short summary
Ice rises are elevated parts of the otherwise flat ice shelf. Here we study the impact of an Antarctic ice rise on the surrounding snow accumulation by combining field data and modeling. Our results show a clear difference in average yearly snow accumulation between the windward side, the leeward side and the peak of the ice rise due to differences in snowfall and wind erosion. This is relevant for the interpretation of ice core records, which are often drilled on the peak of an ice rise.
Michael Studinger, Brooke C. Medley, Kelly M. Brunt, Kimberly A. Casey, Nathan T. Kurtz, Serdar S. Manizade, Thomas A. Neumann, and Thomas B. Overly
The Cryosphere, 14, 3287–3308,Short summary
We use repeat airborne geophysical data consisting of laser altimetry, snow, and Ku-band radar and optical imagery to analyze the spatial and temporal variability in surface roughness, slope, wind deposition, and snow accumulation at 88° S. We find small–scale variability in snow accumulation based on the snow radar subsurface layering, indicating areas of strong wind redistribution are prevalent at 88° S. There is no slope–independent relationship between surface roughness and accumulation.
Ronja Reese, Anders Levermann, Torsten Albrecht, Hélène Seroussi, and Ricarda Winkelmann
The Cryosphere, 14, 3097–3110,Short summary
We compare 21st century projections of Antarctica's future sea-level contribution simulated with the Parallel Ice Sheet Model submitted to ISMIP6 with projections following the LARMIP-2 protocol based on the same model configuration. We find that (1) a preceding historic simulation increases mass loss by 5–50 % and that (2) the order of magnitude difference in the ice loss in our experiments following the two protocols can be explained by the translation of ocean forcing to sub-shelf melting.
Hélène Seroussi, 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, Roderik S. W. van de Wal, Ricarda Winkelmann, Chen Zhao, Tong Zhang, and Thomas Zwinger
The Cryosphere, 14, 3033–3070,Short summary
The Antarctic ice sheet has been losing mass over at least the past 3 decades in response to changes in atmospheric and oceanic conditions. This study presents an ensemble of model simulations of the Antarctic evolution over the 2015–2100 period based on various ice sheet models, climate forcings and emission scenarios. Results suggest that the West Antarctic ice sheet will continue losing a large amount of ice, while the East Antarctic ice sheet could experience increased snow accumulation.
Tom A. Jordan, David Porter, Kirsty Tinto, Romain Millan, Atsuhiro Muto, Kelly Hogan, Robert D. Larter, Alastair G. C. Graham, and John D. Paden
The Cryosphere, 14, 2869–2882,Short summary
Linking ocean and ice sheet processes allows prediction of sea level change. Ice shelves form a floating buffer between the ice–ocean systems, but the water depth beneath is often a mystery, leaving a critical blind spot in our understanding of how these systems interact. Here, we use airborne measurements of gravity to reveal the bathymetry under the ice shelves flanking the rapidly changing Thwaites Glacier and adjacent glacier systems, providing new insights and data for future models.
Kelly A. Hogan, Robert D. Larter, Alastair G. C. Graham, Robert Arthern, James D. Kirkham, Rebecca Totten Minzoni, Tom A. Jordan, Rachel Clark, Victoria Fitzgerald, Anna K. Wåhlin, John B. Anderson, Claus-Dieter Hillenbrand, Frank O. Nitsche, Lauren Simkins, James A. Smith, Karsten Gohl, Jan Erik Arndt, Jongkuk Hong, and Julia Wellner
The Cryosphere, 14, 2883–2908,Short summary
The sea-floor geometry around the rapidly changing Thwaites Glacier is a key control on warm ocean waters reaching the ice shelf and grounding zone beyond. This area was previously unsurveyed due to icebergs and sea-ice cover. The International Thwaites Glacier Collaboration mapped this area for the first time in 2019. The data reveal troughs over 1200 m deep and, as this region is thought to have only ungrounded recently, provide key insights into the morphology beneath the grounded ice sheet.
Stefanie Arndt, Mario Hoppmann, Holger Schmithüsen, Alexander D. Fraser, and Marcel Nicolaus
The Cryosphere, 14, 2775–2793,
Marie-Laure Roussel, Florentin Lemonnier, Christophe Genthon, and Gerhard Krinner
The Cryosphere, 14, 2715–2727,Short summary
The Antarctic precipitation is evaluated against space radar data in the most recent climate model intercomparison CMIP6 and reanalysis ERA5. The seasonal cycle is mostly well reproduced, but relative errors are higher in areas of complex topography, particularly in the higher-resolution models. At continental and regional scales all results are biased high, with no significant progress in the more recent models. Predicting Antarctic contribution to sea level still requires model improvements.
Allie Balter-Kennedy, Gordon Bromley, Greg Balco, Holly Thomas, and Margaret S. Jackson
The Cryosphere, 14, 2647–2672,Short summary
We describe new geologic evidence from Antarctica that demonstrates changes in East Antarctic Ice Sheet (EAIS) extent over the past ~ 15 million years. Our data show that the EAIS was a persistent feature in the Transantarctic Mountains for much of that time, including some (but not all) times when global temperature may have been warmer than today. Overall, our results comprise a long-term record of EAIS change and may provide useful constraints for ice sheet models and sea-level estimates.
Sophie Nowicki, Heiko Goelzer, Hélène Seroussi, Anthony J. Payne, William H. Lipscomb, Ayako Abe-Ouchi, Cécile Agosta, Patrick Alexander, Xylar S. Asay-Davis, Alice Barthel, Thomas J. Bracegirdle, Richard Cullather, Denis Felikson, Xavier Fettweis, Jonathan M. Gregory, Tore Hattermann, Nicolas C. Jourdain, Peter Kuipers Munneke, Eric Larour, Christopher M. Little, Mathieu Morlighem, Isabel Nias, Andrew Shepherd, Erika Simon, Donald Slater, Robin S. Smith, Fiammetta Straneo, Luke D. Trusel, Michiel R. van den Broeke, and Roderik van de Wal
The Cryosphere, 14, 2331–2368,Short summary
This paper describes the experimental protocol for ice sheet models taking part in the Ice Sheet Model Intercomparion Project for CMIP6 (ISMIP6) and presents an overview of the atmospheric and oceanic datasets to be used for the simulations. The ISMIP6 framework allows for exploring the uncertainty in 21st century sea level change from the Greenland and Antarctic ice sheets.
Eric Keenan, Nander Wever, Marissa Dattler, Jan T. M. Lenaerts, Brooke Medley, Peter Kuipers Munneke, and Carleen Reijmer
The Cryosphere Discuss.,
Revised manuscript accepted for TCShort summary
Snow density is required to convert observed changes in ice sheet volume into mass, which ultimately drives ice sheet contribution to sea level rise. However, snow properties respond dynamically to wind driven redistribution. Here we include a new wind driven snow density scheme into an existing snow model. Our results demonstrate an improved representation of snow density when compared to observations and can therefore be used to improve retrievals of ice sheet mass balance.
Bertie W. J. Miles, Jim R. Jordan, Chris R. Stokes, Stewart S. R. Jamieson, G. Hilmar Gudmundsson, and Adrian Jenkins
The Cryosphere Discuss.,
Revised manuscript accepted for TCShort summary
We provide an historical overview of changes in Denman Glacier’s flow speed, structure and calving events since the 1960s. Based on these observations, we perform a series of numerical modelling experiments to determine the likely cause of Denman’s acceleration since the 1970s. We show that a combination of grounding line retreat, ice shelf thinning and the detachment of Denman’s ice tongue from a pinning point are the most likely causes of the observed acceleration.
Marion Donat-Magnin, Nicolas C. Jourdain, Christoph Kittel, Cécile Agosta, Charles Amory, Hubert Gallée, Gerhard Krinner, and Mondher Chekki
The Cryosphere Discuss.,
Revised manuscript accepted for TCShort summary
We simulate the West Antarctic climate in 2100 under increasing greenhouse gases. Future accumulation over the ice sheet increases, which reduces sea level changing rate. Surface ice-shelf melt rates increase until 2100. Some ice shelves experience a lot of liquid water at their surface, which lead ice-shelf collapses. In contrast, no liquid water is found over other ice shelves, due to huge amounts of snowfall, as snow porosity traps liquid water, favouring refreezing and ice shelf stability.
Neil Ross, Hugh Corr, and Martin Siegert
The Cryosphere, 14, 2103–2114,Short summary
Using airborne ice-penetrating radar we investigated the physical properties and structure of the West Antarctic Ice Sheet. Ice deep beneath the Institute Ice Stream has prominent layers with physical properties distinct from those around them and which are heavily folded like geological layers. In turn, these folds influence the present-day flow of the ice sheet, with implications for how computer models are used to simulate ice sheet flow and behaviour in a warming world.
Aurélien Quiquet and Christophe Dumas
The Cryosphere Discuss.,
Preprint under review for TCShort summary
We present here the GRISLI-LSCE contribution to the Ice Sheet Model Intercomparison Project for CMIP6 for Antarctica. The project aims at quantifying the ice sheet contribution to global sea level rise for the next century. We show that increase precipitation in the future in some cases mitigate this contribution with positive to negative values in 2100 depending of the climate forcing used. Sub-shelf basal melt uncertainties induce large differences in simulated grounding line retreats.
The Cryosphere, 14, 1713–1725,Short summary
This paper presents an assessment of drifting-snow occurrences and snow mass transport from up to 9 years (2010–2018) of half-hourly observational records collected at two remote locations in coastal Adelie Land (East Antarctica) using second-generation IAV Engineering acoustic FlowCapt sensors. The dataset is freely available to the scientific community and can be used to complement satellite products and evaluate snow-transport models close to the surface and at high temporal frequency.
Nicolas Jullien, Étienne Vignon, Michael Sprenger, Franziska Aemisegger, and Alexis Berne
The Cryosphere, 14, 1685–1702,Short summary
Although snowfall is the main input of water to the Antarctic ice sheet, snowflakes are often evaporated by dry and fierce winds near the surface of the continent. The amount of snow that actually reaches the ground is therefore considerably reduced. By analyzing the position of cyclones and fronts as well as by back-tracing the atmospheric moisture pathway towards Antarctica, this study explains in which meteorological conditions snowfall is either completely evaporated or reaches the ground.
Luciano Marquetto, Susan Kaspari, and Jefferson Cardia Simões
The Cryosphere, 14, 1537–1554,Short summary
Black carbon, commonly known as soot, is a particle originating from the incomplete combustion of fossil fuels and biomass burning that plays an important role in the climatic system. In this work, we analyzed black carbon from an Antarctic ice core spanning 1968–2015 and observed very low concentrations of this particle in the snow, lower than previous works in West Antarctica. We suggest that black carbon transport to East Antarctica is different from its transport to West Antarctica.
Andreas Wernecke, Tamsin L. Edwards, Isabel J. Nias, Philip B. Holden, and Neil R. Edwards
The Cryosphere, 14, 1459–1474,Short summary
We investigate how the two-dimensional characteristics of ice thickness change from satellite measurements can be used to judge and refine a high-resolution ice sheet model of Antarctica. The uncertainty in 50-year model simulations for the currently most drastically changing part of Antarctica can be reduced by nearly 40 % compared to a simpler, non-spatial approach and nearly 90 % compared to the original spread in simulations.
Quentin Dalaiden, Hugues Goosse, François Klein, Jan T. M. Lenaerts, Max Holloway, Louise Sime, and Elizabeth R. Thomas
The Cryosphere, 14, 1187–1207,Short summary
Large uncertainties remain in Antarctic surface temperature reconstructions over the last millennium. Here, the analysis of climate model outputs reveals that snow accumulation is a more relevant proxy for surface temperature reconstructions than δ18O. We use this finding in data assimilation experiments to compare to observed surface temperatures. We show that our continental temperature reconstruction outperforms reconstructions based on δ18O, especially for East Antarctica.
Mohammad Farzamian, Gonçalo Vieira, Fernando A. Monteiro Santos, Borhan Yaghoobi Tabar, Christian Hauck, Maria Catarina Paz, Ivo Bernardo, Miguel Ramos, and Miguel Angel de Pablo
The Cryosphere, 14, 1105–1120,Short summary
A 2-D automated electrical resistivity tomography (A-ERT) system was installed for the first time in Antarctica at Deception Island to (i) monitor subsurface freezing and thawing processes on a daily and seasonal basis and map the spatial and temporal variability of thaw depth and to (ii) study the impact of short-lived extreme meteorological events on active layer dynamics.
Andrew R. D. Smedley, Geoffrey W. Evatt, Amy Mallinson, and Eleanor Harvey
The Cryosphere, 14, 789–809,
Torsten Albrecht, Ricarda Winkelmann, and Anders Levermann
The Cryosphere, 14, 599–632,Short summary
During the last glacial cycles the Antarctic Ice Sheet experienced alternating climatic conditions and varying sea-level history. In response, changes in ice sheet volume and ice-covered area occurred, implying feedbacks on the global sea level. We ran model simulations of the ice sheet with the Parallel Ice Sheet Model (PISM) over the last two glacial cycles to evaluate the model's sensitivity to different choices of boundary conditions and parameters to gain confidence for future projections.
Torsten Albrecht, Ricarda Winkelmann, and Anders Levermann
The Cryosphere, 14, 633–656,Short summary
A large ensemble of glacial-cycle simulations of the Antarctic Ice Sheet with the Parallel Ice Sheet Model (PISM) was analyzed in which four relevant model parameters were systematically varied. These parameters were selected in a companion study and are associated with uncertainties in ice dynamics, climatic forcing, basal sliding and solid Earth deformation. For each ensemble member a statistical score is computed, which enables calibrating the model against both modern and geologic data.
Jaroslav Obu, Sebastian Westermann, Gonçalo Vieira, Andrey Abramov, Megan Ruby Balks, Annett Bartsch, Filip Hrbáček, Andreas Kääb, and Miguel Ramos
The Cryosphere, 14, 497–519,Short summary
Little is known about permafrost in the Antarctic outside of the few research stations. We used a simple equilibrium permafrost model to estimate permafrost temperatures in the whole Antarctic. The lowest permafrost temperature on Earth is −36 °C in the Queen Elizabeth Range in the Transantarctic Mountains. Temperatures are commonly between −23 and −18 °C in mountainous areas rising above the Antarctic Ice Sheet, between −14 and −8 °C in coastal areas, and up to 0 °C on the Antarctic Peninsula.
Hailong Wang, Jeremy G. Fyke, Jan T. M. Lenaerts, Jesse M. Nusbaumer, Hansi Singh, David Noone, Philip J. Rasch, and Rudong Zhang
The Cryosphere, 14, 429–444,Short summary
Using a climate model with unique water source tagging, we found that sea-ice anomalies in the Southern Ocean and accompanying SST changes have a significant influence on Antarctic precipitation and its source attribution through their direct impact on moisture sources and indirect impact on moisture transport. This study also highlights the importance of atmospheric dynamics in affecting the thermodynamic impact of sea-ice anomalies on regional Antarctic precipitation.
Ruth Mottram, Nicolaj Hansen, Christoph Kittel, Melchior van Wessem, Cécile Agosta, Charles Amory, Fredrik Boberg, Willem Jan van de Berg, Xavier Fettweis, Alexandra Gossart, Nicole P. M. van Lipzig, Erik van Meijgaard, Andrew Orr, Tony Phillips, Stuart Webster, Sebastian B. Simonsen, and Niels Souverijns
The Cryosphere Discuss.,
Revised manuscript accepted for TCShort summary
We compare 5 different regional climate models in Antarctica that all calculate surface mass budget (SMB), the balance between snowfall and surface snow melt. Temperature, air pressure and wind from models match well with observations but SMB is hard to assess as models perform better or worse in different ways and are most different in areas with very few observations. We estimate the average Antarctic surface mass budget is ~ 2300 Gt per year but models vary from this by ~ 10 % more or less.
Marion Donat-Magnin, Nicolas C. Jourdain, Hubert Gallée, Charles Amory, Christoph Kittel, Xavier Fettweis, Jonathan D. Wille, Vincent Favier, Amine Drira, and Cécile Agosta
The Cryosphere, 14, 229–249,Short summary
Modeling the interannual variability of the surface conditions over Antarctic glaciers is important for the identification of climate trends and climate predictions and to assess models. We simulate snow accumulation and surface melting in the Amundsen sector (West Antarctica) over 1979–2017. For all the glaciers, the interannual variability of summer snow accumulation and surface melting is driven by two distinct mechanisms related to variations in the Amundsen Sea Low strength and position.
Detlev Helmig, Daniel Liptzin, Jacques Hueber, and Joel Savarino
The Cryosphere, 14, 199–209,Short summary
We present 15 months of trace gas observations from air withdrawn within the snowpack and from above the snow at Concordia Station in Antarctica. The data show occasional positive spikes, indicative of pollution from the station generator. The pollution signal can be seen in snowpack air shortly after it is observed above the snow surface, and lasting for up to several days, much longer than above the surface.
William H. Lipscomb, Gunter R. Leguy, Nicolas C. Jourdain, Xylar S. Asay-Davis, Hélène Seroussi, and Sophie Nowicki
The Cryosphere Discuss.,
Revised manuscript accepted for TCShort summary
This paper describes Antarctic climate change experiments in which the Community Ice Sheet Model is forced with ocean warming predicted by global climate models. Generally, ice loss begins slowly, accelerates by 2100, and then continues unabated, with widespread retreat of the West Antarctic Ice Sheet. The mass loss by 2500 varies widely, from 10 cm to 2 m of equivalent sea level rise, based on the predicted ocean warming and assumptions about how this warming drives melting beneath ice shelves.
Perry Spector, John Stone, and Brent Goehring
The Cryosphere, 13, 3061–3075,Short summary
We describe constraints on the thickness of the interior of the West Antarctic Ice Sheet (WAIS) through the last deglaciation. Our data imply that the ice-sheet divide between the Ross and Weddell sea sectors of the WAIS was thicker than present for a period less than ~ 8 kyr within the past ~ 15 kyr. These results are consistent with the hypothesis that the divide initially thickened due to the deglacial rise in snowfall and subsequently thinned in response to retreat of the ice-sheet margin.
Keir A. Nichols, Brent M. Goehring, Greg Balco, Joanne S. Johnson, Andrew S. Hein, and Claire Todd
The Cryosphere, 13, 2935–2951,Short summary
We studied the history of ice masses at three locations in the Weddell Sea Embayment, Antarctica. We measured rare isotopes in material sourced from mountains overlooking the Slessor Glacier, Foundation Ice Stream, and smaller glaciers on the Lassiter Coast. We show that ice masses were between 385 and 800 m thicker during the last glacial cycle than they are at present. The ice masses were both hundreds of metres thicker and remained thicker closer to the present than was previously thought.
Jan De Rydt, Gudmundur Hilmar Gudmundsson, Thomas Nagler, and Jan Wuite
The Cryosphere, 13, 2771–2787,Short summary
Two large icebergs are about to break off from the Brunt Ice Shelf in Antarctica. Rifting started several years ago and is now approaching its final phase. Satellite data and computer simulations show that over the past 2 decades, growth of the ice shelf has caused a build-up of forces within the ice, which culminated in its fracture. These natural changes in geometry coincided with large variations in flow speed, a process that is thought to be relevant for all Antarctic ice shelf margins.
Özgür Gürses, Vanessa Kolatschek, Qiang Wang, and Christian Bernd Rodehacke
The Cryosphere, 13, 2317–2324,Short summary
The warming of the Earth's climate system causes sea level rise. In Antarctica, ice streams flow into the sea and develop ice shelves. These are floating extensions of the ice streams. Ocean water melts these ice shelves. It has been proposed that a submarine wall could shield these ice shelves from the warm water. Our model simulation shows that the wall protects ice shelves. However, the warm water flows to neighboring ice shelves. There, enhanced melting reduces the effectiveness of the wall.
Johannes Sutter, Hubertus Fischer, Klaus Grosfeld, Nanna B. Karlsson, Thomas Kleiner, Brice Van Liefferinge, and Olaf Eisen
The Cryosphere, 13, 2023–2041,Short summary
The Antarctic Ice Sheet may have played an important role in moderating the transition between warm and cold climate epochs over the last million years. We find that the Antarctic Ice Sheet grew considerably about 0.9 Myr ago, a time when ice-age–warm-age cycles changed from a 40 000 to a 100 000 year periodicity. Our findings also suggest that ice as old as 1.5 Myr still exists at the bottom of the East Antarctic Ice Sheet despite the major climate reorganisations in the past.
Ghislain Picard, Laurent Arnaud, Romain Caneill, Eric Lefebvre, and Maxim Lamare
The Cryosphere, 13, 1983–1999,Short summary
To study how snow accumulates in Antarctica, we analyze daily surface elevation recorded by an automatic laser scanner. We show that new snow often accumulates in thick patches covering a small fraction of the surface. Most patches are removed by erosion within weeks, implying that only a few contribute to the snowpack. This explains the heterogeneity on the surface and in the snowpack. These findings are important for surface mass and energy balance, photochemistry, and ice core interpretation.
James D. Kirkham, Kelly A. Hogan, Robert D. Larter, Neil S. Arnold, Frank O. Nitsche, Nicholas R. Golledge, and Julian A. Dowdeswell
The Cryosphere, 13, 1959–1981,Short summary
A series of huge (500 m wide, 50 m deep) channels were eroded by water flowing beneath Pine Island and Thwaites glaciers in the past. The channels are similar to canyon systems produced by floods of meltwater released beneath the Antarctic Ice Sheet millions of years ago. The spatial extent of the channels formed beneath Pine Island and Thwaites glaciers demonstrates significant quantities of water, possibly discharged from trapped subglacial lakes, flowed beneath these glaciers in the past.
Alley, R. B., Blankenship, D. D., Rooney, S. T., and Bentley, C. R.: Sedimentation beneath ice shelves – the view from ice stream B, Mar. Geol., 85, 101–120, 1989.
Anandakrishnan, S., Voigt, D. E., Alley, R. R., and King, M. A.: Ice stream D flow speed is strongly modulated by the tide beneath the Ross Ice Shelf, Geophys. Res. Lett., 30(7), 1361, https://doi.org/10.1029/2002GL016329, 2003.
Bamber, J. L., Gomez-Dans, J. L., and Griggs, J. A.: A new 1 km digital elevation model of the Antarctic derived from combined satellite radar and laser data – Part 1: Data and methods, The Cryosphere, 3, 101–111, https://doi.org/10.5194/tc-3-101-2009, 2009.
Bindschadler, R. A. and Vornberger, P. L.: Detailed elevation map of ice stream C using satellite imagery and airborne radar, Ann. Glaciol., 20, 327–335, 1994.
Bindschadler, R. A., Vornberger, P. L., King, M., and Padman, L.: Tidally-Driven Stick-Slip Motion in the Mouth of Whillans Ice Stream, Antarctica, Ann. Glaciol., 36, 263–272, 2003.
Bindschadler, R., Vornberger, P., Fleming, A., Fox, A., Mullins, J., Binnie, D., Paulsen, S. J., Granneman, B., and Gorodetzky, D.: The Landsat Image Mosaic of Antarctica, Remote Sens. Environ., 112(12), 4214–4226, https://doi.org/10.1016/j.rse.2008.07.006, 2008.
Bindschadler, R. A., Wichlacz, A., and Choi, H.: An Illustrated Guide to Using ASAID Software, NASA Technical Memorandum, TM-2011-215879, 21 pp., 2011.
Bohlander, J. and Scambos, T.: Antarctic coastlines and grounding line derived from MODIS Mosaic of Antarctica (MOA), Boulder, Colorado USA: National Snow and Ice Data Center, Digital media, 2007.
Brunt, K. M., Fricker, H. A., Padman, L., and O'Neel, S.: ICESat-Derived Grounding Zone for Antarctic Ice Shelves, Boulder, Colorado USA: National Snow and Ice Data Center, Digital media, 2010a.
Brunt, K. M., Fricker, H. A., Padman, L., Scambos, T. A., and O'Neel, S.: Mapping the grounding zone of the Ross Ice Shelf, Antarctica, Using ICESat laser altimetry, Ann. Glaciol., 51(55), 71–79, 2010b.
Corr, H. F. J., Doake, C. S. M., Jenkins, A., and Vaughan, D. G.: Investigations of an "ice plain" in the mouth of Pine Island Glacier, Antarctica, J. Glaciol., 47(156), 51–57, 2001.
Ferrigno, J. G., Mullins, J. L., Stapleton, J. A., Chavez, P. S., Velasco, M. G., Williams, R. S., Delinski, G. F., and Lear, D.: Satellite Image Map of Antarctica, U.S. Geological Survey, Miscellaneous Investigations Map Series, Map 1-2560, 1996.
Fricker, H. A. and Padman, L.: Ice shelf grounding zone structure from ICESat laser altimetry, Geophys. Res. Lett., 33, L15502, https://doi.org/10.1029/2006GL026907, 2006.
Fricker, H. A., Coleman, R., Padman, L., Scambos, T. A., Bohlander, J., and Brunt, K. M.: Mapping the grounding zone of the Amery Ice Shelf, East Antarctica using InSAR, MODIS and ICESat, Antarct. Sci., 21(5), 515–532, https://doi.org/10.1017/S095410200999023X, 2009.
Joughin, I., Smith, B. E., and Holland, D. M.: Sensitivity of 21st Century Sea Level to Ocean-Induced Thinning of Pine Island Glacier, Antarctica, Geophys. Res. Lett., 37, L20502, https://doi.org/10.1029/2010GL044819, 2010.
Korona J., Berthier, E., Bernard, M., Remy, F., and Thouvenot, E.: SPIRIT. SPOT 5 stereoscopic survey of Polar Ice: Reference Images and Topographies during the fourth International Polar Year (2007–2009), ISPRS J. Photogramm., 64, 204–212, 2009.
Lee, D. S., Storey, J. C., Choate, M. J., and Hayes, R. W.: Four Years of Landsat-7 On-Orbit Geometric Calibration and Performance, IEEE T. Geosci. Remote, 42(12), 2786–2795, https://doi.org/10.1109/TGRS.2004.836769, 2004.
Liu, H., Jezek, K., Li, B., and Zhao, Z.: Radarsat Antarctic Mapping Project digital elevation model version 2, Boulder, CO: National Snow and Ice Data Center, Digital media, 2001.
Lythe, M. B., Vaughan, D. G., and BEDMAP Consortium, BEDMAP: A new ice thickness and subglacial topographic model of Antarctica, J. Geophys. Res., 106(B6), 11335–11351, 2001.
Payne, A. J., Vieli, A., Shepherd, A. P., Wingham, D. J., and Rignot, E.: Recent dramatic thinning of largest West Antarctic ice stream triggered by oceans, Geophys. Res. Lett., 31(23), L23401, https://doi.org/10.1029/2004GL021284, 2004.
Payne, A. J., Holland, P. R., Shepherd, A. P., Rutt, I. C., Jenkins, A., and Joughin, I.: Numerical modeling of ocean-ice interactions under Pine Island Bay's ice shelf, J. Geophys. Res., 112, C10019, https://doi.org/10.1029/2006JC003733, 2007.
Pritchard, H. D., Arthern, R. J., Vaughan, D. G., and Edwards, L. A.: Extensive dynamic thinning on the margins of the Greenland and Antarctic ice sheets, Nature, 461, 971–975, https://doi.org/10.1038/nature08471, 2009.
Rignot, E.: Tidal motion, ice velocity and melt rate of Petermann Gletscher, Greenland, measured from radar interferometry, J. Glaciol., 42(142), 476–485, 1996.
Rignot, E., Bamber, J. L., van den Broeke, M. R., Davis, C., Yonghong, L., van deBerg, W. J., and van Meijgaard, E.: Recent Antarctic ice mass loss from radar interferometry and regional climate modeling, Nat. Geosci., 1, 106–110, https://doi.org/10.1038/ngeo102, 2008.
Rignot, E., Mouginot, J., and Scheuchl, B.: Antarctic grounding line mapping from differential satellite radar interferometry, Geophys. Res. Lett., 38, L10504, https://doi.org/10.1029/2011GL047109, 2011.
Schoof, C.: Ice sheet grounding line dynamics: Steady states, stability, and hysteresis, J. Geophys. Res., 112, F03S28, https://doi.org/10.1029/2006JF000664, 2007.
Shepherd, A., Wingham, D. J., and Mansley, J. A. D.: Inland thinning of the Amundsen Sea sector, Geophys. Res. Lett., 29(10), 1364, https://doi.org/10.1029/2001GL014183, 2002.
Thomas, R., Rignot, E., Casassa, G., Kanagaratnam, P., Acuna, C., Akins, T., Brecher, H., Frederick, E., Gogineni, P., Krabill, W., Manizade, S., Ramamoorthy, H., Rivera, A., Russell, R., Sonntag, J., Swift, R., Yungel, J., and Zwally, J.: Accelerated sea-level rise from West Antarctica, Science, 306(5694), 255–258, 2004.
Thomas, R. H., Stephenson, S. N., Bindschadler, R. A., Shabtaie, S., and Bentley, C. R.: Thinning and grounding line retreat on the Ross Ice Shelf, Ann. Glaciol., 11, 165–172, 1988.
van den Broeke, M. R., van de Berg, W. J., and van Meijgaard, E.: Firn depth correction along the Antarctic grounding line, Antarct. Sci., 20(5), 1–5, https://doi.org/10.1017/S095410200800148X, 2008.
Vaughan, D. G.: Tidal Flexure at Ice Sheet Margins, J. Geophys. Res., 100(B4), 6213–6224, 1995.
Wiens, D. A., Anandakrishnan, S., Winberry, J. P., and King, M. A.: Simultaneous teleseismic and geodetic observations of the stick-slip motion of an Antarctic ice stream, Nature, 453, 770–774, https://doi.org/10.1038/nature06990, 2008.
Wildey, R. L.: Generalized photoclinometry for Mariner 9, Icarus, 25, 613–626, 1975.
Yamanokuchi, T., Doi, K., and Shibuya, K.: Validation of grounding line of the East Antarctic Ice Sheet derived by ERS-1/2 interferometric SAR data, Polar Geoscience, 18, 1–14, 2005.
Zwally, H. J., Schutz, R., Bentley, C., Bufton, J., Herring, T., Minster, J., Spinhirne, J., and Thomas, R.: GLAS/ICESat L2 Antarctic and Greenland Ice Sheet Altimetry Data V001, Boulder, CO: National Snow and Ice Data Center, Digital media, 2003.