Articles | Volume 8, issue 3
The Cryosphere, 8, 867–875, 2014
https://doi.org/10.5194/tc-8-867-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
The Cryosphere, 8, 867–875, 2014
https://doi.org/10.5194/tc-8-867-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
13 May 2014
Research article
| 13 May 2014
Transition of flow regime along a marine-terminating outlet glacier in East Antarctica
D. Callens et al.
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Brooke Medley, Thomas A. Neumann, H. Jay Zwally, and Benjamin E. Smith
The Cryosphere Discuss., https://doi.org/10.5194/tc-2020-266, https://doi.org/10.5194/tc-2020-266, 2020
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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, https://doi.org/10.5194/tc-14-3367-2020, https://doi.org/10.5194/tc-14-3367-2020, 2020
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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, https://doi.org/10.5194/tc-14-3033-2020, https://doi.org/10.5194/tc-14-3033-2020, 2020
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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.
Heiko Goelzer, Violaine Coulon, Frank Pattyn, Bas de Boer, and Roderik van de Wal
The Cryosphere, 14, 833–840, https://doi.org/10.5194/tc-14-833-2020, https://doi.org/10.5194/tc-14-833-2020, 2020
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Ian Joughin, David E. Shean, Benjamin E. Smith, and Dana Floricioiu
The Cryosphere, 14, 211–227, https://doi.org/10.5194/tc-14-211-2020, https://doi.org/10.5194/tc-14-211-2020, 2020
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David A. Lilien, Ian Joughin, Benjamin Smith, and Noel Gourmelen
The Cryosphere, 13, 2817–2834, https://doi.org/10.5194/tc-13-2817-2019, https://doi.org/10.5194/tc-13-2817-2019, 2019
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We used a number of computer simulations to understand the recent retreat of a rapidly changing group of glaciers in West Antarctica. We found that significant melt underneath the floating extensions of the glaciers, driven by relatively warm ocean water at depth, was likely needed to cause the large retreat that has been observed. If melt continues around current rates, retreat is likely to continue through the coming century and extend beyond the present-day drainage area of these glaciers.
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
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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.
Katrin Lindbäck, Geir Moholdt, Keith W. Nicholls, Tore Hattermann, Bhanu Pratap, Meloth Thamban, and Kenichi Matsuoka
The Cryosphere, 13, 2579–2595, https://doi.org/10.5194/tc-13-2579-2019, https://doi.org/10.5194/tc-13-2579-2019, 2019
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In this study, we used a ground-penetrating radar technique to measure melting at high precision under Nivlisen, an ice shelf in central Dronning Maud Land, East Antarctica. We found that summer-warmed ocean surface waters can increase melting close to the ice shelf front. Our study shows the use of and need for measurements in the field to monitor Antarctica's coastal margins; these detailed variations in basal melting are not captured in satellite data but are vital to predict future changes.
Hélène Seroussi, Sophie Nowicki, Erika Simon, Ayako Abe-Ouchi, Torsten Albrecht, Julien Brondex, Stephen Cornford, Christophe Dumas, Fabien Gillet-Chaulet, Heiko Goelzer, Nicholas R. Golledge, Jonathan M. Gregory, Ralf Greve, Matthew J. Hoffman, Angelika Humbert, Philippe Huybrechts, Thomas Kleiner, Eric Larour, Gunter Leguy, William H. Lipscomb, Daniel Lowry, Matthias Mengel, Mathieu Morlighem, Frank Pattyn, Anthony J. Payne, David Pollard, Stephen F. Price, Aurélien Quiquet, Thomas J. Reerink, Ronja Reese, Christian B. Rodehacke, Nicole-Jeanne Schlegel, Andrew Shepherd, Sainan Sun, Johannes Sutter, Jonas Van Breedam, Roderik S. W. van de Wal, Ricarda Winkelmann, and Tong Zhang
The Cryosphere, 13, 1441–1471, https://doi.org/10.5194/tc-13-1441-2019, https://doi.org/10.5194/tc-13-1441-2019, 2019
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We compare a wide range of Antarctic ice sheet simulations with varying initialization techniques and model parameters to understand the role they play on the projected evolution of this ice sheet under simple scenarios. Results are improved compared to previous assessments and show that continued improvements in the representation of the floating ice around Antarctica are critical to reduce the uncertainty in the future ice sheet contribution to sea level rise.
Kevin Bulthuis, Maarten Arnst, Sainan Sun, and Frank Pattyn
The Cryosphere, 13, 1349–1380, https://doi.org/10.5194/tc-13-1349-2019, https://doi.org/10.5194/tc-13-1349-2019, 2019
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Using probabilistic methods, we quantify the uncertainty in the Antarctic ice-sheet response to climate change over the next millennium under the four RCP scenarios and parametric uncertainty. We find that the ice sheet is stable in RCP 2.6 regardless of parametric uncertainty, while West Antarctica undergoes disintegration in RCP 8.5 almost regardless of parametric uncertainty. We also show a high sensitivity of the ice-sheet response to uncertainty in sub-shelf melting and sliding conditions.
Ian M. Howat, Claire Porter, Benjamin E. Smith, Myoung-Jong Noh, and Paul Morin
The Cryosphere, 13, 665–674, https://doi.org/10.5194/tc-13-665-2019, https://doi.org/10.5194/tc-13-665-2019, 2019
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The Reference Elevation Model of Antarctica (REMA) is the first continental-scale terrain map at less than 10 m resolution, and the first with a time stamp, enabling measurements of elevation change. REMA is constructed from over 300 000 individual stereoscopic elevation models (DEMs) extracted from submeter-resolution satellite imagery. REMA is vertically registered to satellite altimetry, resulting in errors of less than 1 m over most of its area and relative uncertainties of decimeters.
Katrin Lindbäck, Jack Kohler, Rickard Pettersson, Christopher Nuth, Kirsty Langley, Alexandra Messerli, Dorothée Vallot, Kenichi Matsuoka, and Ola Brandt
Earth Syst. Sci. Data, 10, 1769–1781, https://doi.org/10.5194/essd-10-1769-2018, https://doi.org/10.5194/essd-10-1769-2018, 2018
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Tidewater glaciers terminate directly into the sea and the glacier fronts are important feeding areas for birds and marine mammals. Svalbard tidewater glaciers are retreating, which will affect fjord circulation and ecosystems when glacier fronts end on land. In this paper, we present digital maps of ice thickness and topography under five tidewater glaciers in Kongsfjorden, northwestern Svalbard, which will be useful in studies of future glacier changes in the area.
Brice Van Liefferinge, Frank Pattyn, Marie G. P. Cavitte, Nanna B. Karlsson, Duncan A. Young, Johannes Sutter, and Olaf Eisen
The Cryosphere, 12, 2773–2787, https://doi.org/10.5194/tc-12-2773-2018, https://doi.org/10.5194/tc-12-2773-2018, 2018
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Our paper provides an important review of the state of knowledge for oldest-ice prospection, but also adds new basal geothermal heat flux constraints from recently acquired high-definition radar data sets. This is the first paper to contrast the two primary target regions for oldest ice: Dome C and Dome Fuji. Moreover, we provide statistical comparisons of all available data sets and a summary of the community's criteria for the retrieval of interpretable oldest ice since the 2013 effort.
Nanna B. Karlsson, Tobias Binder, Graeme Eagles, Veit Helm, Frank Pattyn, Brice Van Liefferinge, and Olaf Eisen
The Cryosphere, 12, 2413–2424, https://doi.org/10.5194/tc-12-2413-2018, https://doi.org/10.5194/tc-12-2413-2018, 2018
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In this study, we investigate the probability that the Dome Fuji region in East Antarctica contains ice more than 1.5 Ma old. The retrieval of a continuous ice-core record extending beyond 1 Ma is imperative to understand why the frequency of ice ages changed from 40 to 100 ka approximately 1 Ma ago.
We use a new radar dataset to improve the ice thickness maps, and apply a thermokinematic model to predict basal temperature and age of the ice. Our results indicate several areas of interest.
Ian Joughin, Ben E. Smith, and Ian Howat
The Cryosphere, 12, 2211–2227, https://doi.org/10.5194/tc-12-2211-2018, https://doi.org/10.5194/tc-12-2211-2018, 2018
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We describe several new ice velocity maps produced using Landsat 8 and Copernicus Sentinel 1A/B data. We focus on several sites where we analyse these data in conjunction with earlier data from this project, which extend back to the year 2000. In particular, we find that Jakobshavn Isbræ began slowing substantially in 2017. The growing duration of these records will allow more robust analyses of the processes controlling fast flow and how they are affected by climate and other forcings.
Heiko Goelzer, Sophie Nowicki, Tamsin Edwards, Matthew Beckley, Ayako Abe-Ouchi, Andy Aschwanden, Reinhard Calov, Olivier Gagliardini, Fabien Gillet-Chaulet, Nicholas R. Golledge, Jonathan Gregory, Ralf Greve, Angelika Humbert, Philippe Huybrechts, Joseph H. Kennedy, Eric Larour, William H. Lipscomb, Sébastien Le clec'h, Victoria Lee, Mathieu Morlighem, Frank Pattyn, Antony J. Payne, Christian Rodehacke, Martin Rückamp, Fuyuki Saito, Nicole Schlegel, Helene Seroussi, Andrew Shepherd, Sainan Sun, Roderik van de Wal, and Florian A. Ziemen
The Cryosphere, 12, 1433–1460, https://doi.org/10.5194/tc-12-1433-2018, https://doi.org/10.5194/tc-12-1433-2018, 2018
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We have compared a wide spectrum of different initialisation techniques used in the ice sheet modelling community to define the modelled present-day Greenland ice sheet state as a starting point for physically based future-sea-level-change projections. Compared to earlier community-wide comparisons, we find better agreement across different models, which implies overall improvement of our understanding of what is needed to produce such initial states.
David A. Lilien, Ian Joughin, Benjamin Smith, and David E. Shean
The Cryosphere, 12, 1415–1431, https://doi.org/10.5194/tc-12-1415-2018, https://doi.org/10.5194/tc-12-1415-2018, 2018
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We used remotely sensed data and a numerical model to study the processes controlling the stability of two rapidly changing ice shelves in West Antarctica. Both these ice shelves have been losing mass since at least 1996, primarily as a result of ocean-forced melt. We find that this imbalance likely results from changes initiated around 1970 or earlier. Our results also show that the shelves’ differing speedup is controlled by the strength of their margins and their grounding-line positions.
David E. Shean, Knut Christianson, Kristine M. Larson, Stefan R. M. Ligtenberg, Ian R. Joughin, Ben E. Smith, C. Max Stevens, Mitchell Bushuk, and David M. Holland
The Cryosphere, 11, 2655–2674, https://doi.org/10.5194/tc-11-2655-2017, https://doi.org/10.5194/tc-11-2655-2017, 2017
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We used long-term GPS data and interferometric reflectometry (GPS-IR) to measure velocity, strain rate and surface elevation for the PIG ice shelf – a site of significant mass loss in recent decades. We combined these observations with high-res DEMs and firn model output to constrain surface mass balance and basal melt rates. We document notable spatial variability in basal melt rates but limited temporal variability from 2012 to 2014 despite significant changes in sub-shelf ocean heat content.
Sophie Berger, Reinhard Drews, Veit Helm, Sainan Sun, and Frank Pattyn
The Cryosphere, 11, 2675–2690, https://doi.org/10.5194/tc-11-2675-2017, https://doi.org/10.5194/tc-11-2675-2017, 2017
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Floating ice shelves act as a plug for the Antarctic ice sheet. The efficiency of this ice plug depends on how and how much the ocean melts the ice from below. This study relies on satellite imagery and a Lagrangian approach to map in detail the basal mass balance of an Antarctic ice shelf. Although the large-scale melting pattern of the ice shelf agrees with previous studies, our technique successfully detects local variability (< 1 km) in the basal melting of the ice shelf.
Frank Pattyn
The Cryosphere, 11, 1851–1878, https://doi.org/10.5194/tc-11-1851-2017, https://doi.org/10.5194/tc-11-1851-2017, 2017
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Marine Ice Sheet Instability is a mechanism that can potentially lead to collapse of marine sectors of the Antarctic ice sheet and floating ice shelves play a crucial role herein. Improved grounding line physics (interaction with subglacial sediment) are implemented in a new ice-sheet model and compared to traditional sliding laws. Ice shelf collapse leads to a significant higher sea-level contribution (up to 15 m in 500 years) compared to traditional grounding-line approaches.
Benjamin E. Smith, Noel Gourmelen, Alexander Huth, and Ian Joughin
The Cryosphere, 11, 451–467, https://doi.org/10.5194/tc-11-451-2017, https://doi.org/10.5194/tc-11-451-2017, 2017
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In this paper we investigate elevation changes of Thwaites Glacier, West Antarctica, one of the main sources of excess ice discharge into the ocean. We find that in early 2013, four subglacial lakes separated by 100 km drained suddenly, discharging more than 3 km3 of water under the fastest part of the glacier in less than 6 months. Concurrent ice-speed measurements show only minor changes, suggesting that ice dynamics are not strongly sensitive to changes in water flow.
Lionel Favier, Frank Pattyn, Sophie Berger, and Reinhard Drews
The Cryosphere, 10, 2623–2635, https://doi.org/10.5194/tc-10-2623-2016, https://doi.org/10.5194/tc-10-2623-2016, 2016
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We demonstrate the short-term unstable retreat of an East Antarctic outlet glacier triggered by imposed sub-ice-shelf melt, compliant with current values, using a state-of-the-art ice-sheet model. We show that pinning points – topographic highs in contact with the ice-shelf base – have a major impact on ice-sheet stability and timing of grounding-line retreat. The study therefore calls for improving our knowledge of sub-ice-shelf bathymetry in order to reduce uncertainties in future ice loss.
Morgane Philippe, Jean-Louis Tison, Karen Fjøsne, Bryn Hubbard, Helle A. Kjær, Jan T. M. Lenaerts, Reinhard Drews, Simon G. Sheldon, Kevin De Bondt, Philippe Claeys, and Frank Pattyn
The Cryosphere, 10, 2501–2516, https://doi.org/10.5194/tc-10-2501-2016, https://doi.org/10.5194/tc-10-2501-2016, 2016
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The reconstruction of past snow accumulation rates is crucial in the context of recent climate change and sea level rise. We measured ~ 250 years of snow accumulation using a 120 m ice core drilled in coastal East Antarctica, where such long records are very scarce. This study is the first to show an increase in snow accumulation, beginning in the 20th and particularly marked in the last 50 years, thereby confirming model predictions of increased snowfall associated with climate change.
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
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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.
Reinhard Drews, Joel Brown, Kenichi Matsuoka, Emmanuel Witrant, Morgane Philippe, Bryn Hubbard, and Frank Pattyn
The Cryosphere, 10, 811–823, https://doi.org/10.5194/tc-10-811-2016, https://doi.org/10.5194/tc-10-811-2016, 2016
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The thickness of ice shelves is typically inferred using hydrostatic equilibrium which requires knowledge of the firn density. Here, we infer density from wide-angle radar using a novel algorithm including traveltime inversion and ray tracing. We find that firn is denser inside a 2 km wide ice-shelf channel which is confirmed by optical televiewing of two boreholes. Such horizontal density variations must be accounted for when using the hydrostatic ice thickness for determining basal melt rate.
D. N. Goldberg, P. Heimbach, I. Joughin, and B. Smith
The Cryosphere, 9, 2429–2446, https://doi.org/10.5194/tc-9-2429-2015, https://doi.org/10.5194/tc-9-2429-2015, 2015
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We calibrate a time-dependent ice model through optimal fit to transient observations of surface elevation and velocity, a novel procedure in glaciology and in particular for an ice stream with a dynamic grounding line. We show this procedure gives a level of confidence in model projections that cannot be achieved through more commonly used glaciological data assimilation methods. We show that Smith Glacier is in a state of retreat regardless of climatic forcing for the next several decades.
G. Durand and F. Pattyn
The Cryosphere, 9, 2043–2055, https://doi.org/10.5194/tc-9-2043-2015, https://doi.org/10.5194/tc-9-2043-2015, 2015
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Projections of Antarctic dynamics and contribution to sea-level rise are evaluated in the light of intercomparison exercises dedicated to evaluate models' ability of representing coastal changes. Uncertainties in projections can be substantially decreased if a selection of models is made and models that are unqualified for the representation of coastal dynamics are excluded.
A. Diez, O. Eisen, C. Hofstede, A. Lambrecht, C. Mayer, H. Miller, D. Steinhage, T. Binder, and I. Weikusat
The Cryosphere, 9, 385–398, https://doi.org/10.5194/tc-9-385-2015, https://doi.org/10.5194/tc-9-385-2015, 2015
I. M. Howat, C. Porter, M. J. Noh, B. E. Smith, and S. Jeong
The Cryosphere, 9, 103–108, https://doi.org/10.5194/tc-9-103-2015, https://doi.org/10.5194/tc-9-103-2015, 2015
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In the summer of 2011, a large crater appeared in the surface of the Greenland Ice Sheet. It formed when a subglacial lake, equivalent to 10,000 swimming pools, catastrophically drained in less than 14 days. This is the first direct evidence that surface meltwater that drains through cracks to the bed of the ice sheet can build up in subglacial lakes over long periods of time. The sudden drainage may have been due to more surface melting and an increase in meltwater reaching the bed.
R. T. W. L. Hurkmans, J. L. Bamber, C. H. Davis, I. R. Joughin, K. S. Khvorostovsky, B. S. Smith, and N. Schoen
The Cryosphere, 8, 1725–1740, https://doi.org/10.5194/tc-8-1725-2014, https://doi.org/10.5194/tc-8-1725-2014, 2014
I. M. Howat, A. Negrete, and B. E. Smith
The Cryosphere, 8, 1509–1518, https://doi.org/10.5194/tc-8-1509-2014, https://doi.org/10.5194/tc-8-1509-2014, 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
B. Sun, J. C. Moore, T. Zwinger, L. Zhao, D. Steinhage, X. Tang, D. Zhang, X. Cui, and C. Martín
The Cryosphere, 8, 1121–1128, https://doi.org/10.5194/tc-8-1121-2014, https://doi.org/10.5194/tc-8-1121-2014, 2014
D. Di Nitto, G. Neukermans, N. Koedam, H. Defever, F. Pattyn, J. G. Kairo, and F. Dahdouh-Guebas
Biogeosciences, 11, 857–871, https://doi.org/10.5194/bg-11-857-2014, https://doi.org/10.5194/bg-11-857-2014, 2014
M. Thoma, K. Grosfeld, D. Barbi, J. Determann, S. Goeller, C. Mayer, and F. Pattyn
Geosci. Model Dev., 7, 1–21, https://doi.org/10.5194/gmd-7-1-2014, https://doi.org/10.5194/gmd-7-1-2014, 2014
M. J. Siegert, N. Ross, H. Corr, B. Smith, T. Jordan, R. G. Bingham, F. Ferraccioli, D. M. Rippin, and A. Le Brocq
The Cryosphere, 8, 15–24, https://doi.org/10.5194/tc-8-15-2014, https://doi.org/10.5194/tc-8-15-2014, 2014
H. Fischer, J. Severinghaus, E. Brook, E. Wolff, M. Albert, O. Alemany, R. Arthern, C. Bentley, D. Blankenship, J. Chappellaz, T. Creyts, D. Dahl-Jensen, M. Dinn, M. Frezzotti, S. Fujita, H. Gallee, R. Hindmarsh, D. Hudspeth, G. Jugie, K. Kawamura, V. Lipenkov, H. Miller, R. Mulvaney, F. Parrenin, F. Pattyn, C. Ritz, J. Schwander, D. Steinhage, T. van Ommen, and F. Wilhelms
Clim. Past, 9, 2489–2505, https://doi.org/10.5194/cp-9-2489-2013, https://doi.org/10.5194/cp-9-2489-2013, 2013
B. Van Liefferinge and F. Pattyn
Clim. Past, 9, 2335–2345, https://doi.org/10.5194/cp-9-2335-2013, https://doi.org/10.5194/cp-9-2335-2013, 2013
J. L. Bamber, J. A. Griggs, R. T. W. L. Hurkmans, J. A. Dowdeswell, S. P. Gogineni, I. Howat, J. Mouginot, J. Paden, S. Palmer, E. Rignot, and D. Steinhage
The Cryosphere, 7, 499–510, https://doi.org/10.5194/tc-7-499-2013, https://doi.org/10.5194/tc-7-499-2013, 2013
A. S. Drouet, D. Docquier, G. Durand, R. Hindmarsh, F. Pattyn, O. Gagliardini, and T. Zwinger
The Cryosphere, 7, 395–406, https://doi.org/10.5194/tc-7-395-2013, https://doi.org/10.5194/tc-7-395-2013, 2013
P. Fretwell, H. D. Pritchard, D. G. Vaughan, J. L. Bamber, N. E. Barrand, R. Bell, C. Bianchi, R. G. Bingham, D. D. Blankenship, G. Casassa, G. Catania, D. Callens, H. Conway, A. J. Cook, H. F. J. Corr, D. Damaske, V. Damm, F. Ferraccioli, R. Forsberg, S. Fujita, Y. Gim, P. Gogineni, J. A. Griggs, R. C. A. Hindmarsh, P. Holmlund, J. W. Holt, R. W. Jacobel, A. Jenkins, W. Jokat, T. Jordan, E. C. King, J. Kohler, W. Krabill, M. Riger-Kusk, K. A. Langley, G. Leitchenkov, C. Leuschen, B. P. Luyendyk, K. Matsuoka, J. Mouginot, F. O. Nitsche, Y. Nogi, O. A. Nost, S. V. Popov, E. Rignot, D. M. Rippin, A. Rivera, J. Roberts, N. Ross, M. J. Siegert, A. M. Smith, D. Steinhage, M. Studinger, B. Sun, B. K. Tinto, B. C. Welch, D. Wilson, D. A. Young, C. Xiangbin, and A. Zirizzotti
The Cryosphere, 7, 375–393, https://doi.org/10.5194/tc-7-375-2013, https://doi.org/10.5194/tc-7-375-2013, 2013
Related subject area
Subglacial Processes
Persistent, extensive channelized drainage modeled beneath Thwaites Glacier, West Antarctica
Filling and drainage of a subglacial lake beneath the Flade Isblink ice cap, northeast Greenland
Radar sounding survey over Devon Ice Cap indicates the potential for a diverse hypersaline subglacial hydrological environment
Long-period variability in ice-dammed glacier outburst floods due to evolving catchment geometry
Seasonal evolution of basal environment conditions of Russell sector, West Greenland, inverted from satellite observation of surface flow
Grounding zone subglacial properties from calibrated active-source seismic methods
Subglacial carbonate deposits as a potential proxy for a glacier's former presence
Brief communication: Heterogenous thinning and subglacial lake activity on Thwaites Glacier, West Antarctica
Subglacial lakes and hydrology across the Ellsworth Subglacial Highlands, West Antarctica
The role of electrical conductivity in radar wave reflection from glacier beds
Subglacial permafrost dynamics and erosion inside subglacial channels driven by surface events in Svalbard
Review article: Geothermal heat flow in Antarctica: current and future directions
Quantification of seasonal and diurnal dynamics of subglacial channels using seismic observations on an Alpine glacier
Exceptionally high heat flux needed to sustain the Northeast Greenland Ice Stream
Glaciohydraulic seismic tremors on an Alpine glacier
Subglacial roughness of the Greenland Ice Sheet: relationship with contemporary ice velocity and geology
Airborne radionuclides and heavy metals in high Arctic terrestrial environment as the indicators of sources and transfers of contamination
Subglacial hydrological control on flow of an Antarctic Peninsula palaeo-ice stream
Pervasive cold ice within a temperate glacier – implications for glacier thermal regimes, sediment transport and foreland geomorphology
Combined diurnal variations of discharge and hydrochemistry of the Isunnguata Sermia outlet, Greenland Ice Sheet
Connected subglacial lake drainage beneath Thwaites Glacier, West Antarctica
Active subglacial lakes and channelized water flow beneath the Kamb Ice Stream
Sliding of temperate basal ice on a rough, hard bed: creep mechanisms, pressure melting, and implications for ice streaming
Brief Communication: Twelve-year cyclic surging episodes at Donjek Glacier in Yukon, Canada
Tremor during ice-stream stick slip
A new methodology to simulate subglacial deformation of water-saturated granular material
Boundary conditions of an active West Antarctic subglacial lake: implications for storage of water beneath the ice sheet
A balanced water layer concept for subglacial hydrology in large-scale ice sheet models
The "tipping" temperature within Subglacial Lake Ellsworth, West Antarctica and its implications for lake access
Interaction between ice sheet dynamics and subglacial lake circulation: a coupled modelling approach
Alexander O. Hager, Matthew J. Hoffman, Stephen F. Price, and Dustin M. Schroeder
The Cryosphere, 16, 3575–3599, https://doi.org/10.5194/tc-16-3575-2022, https://doi.org/10.5194/tc-16-3575-2022, 2022
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The presence of water beneath glaciers is a control on glacier speed and ocean-caused melting, yet it has been unclear whether sizable volumes of water can exist beneath Antarctic glaciers or how this water may flow along the glacier bed. We use computer simulations, supported by observations, to show that enough water exists at the base of Thwaites Glacier, Antarctica, to form "rivers" beneath the glacier. These rivers likely moderate glacier speed and may influence its rate of retreat.
Qi Liang, Wanxin Xiao, Ian Howat, Xiao Cheng, Fengming Hui, Zhuoqi Chen, Mi Jiang, and Lei Zheng
The Cryosphere, 16, 2671–2681, https://doi.org/10.5194/tc-16-2671-2022, https://doi.org/10.5194/tc-16-2671-2022, 2022
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Using multi-temporal ArcticDEM and ICESat-2 altimetry data, we document changes in surface elevation of a subglacial lake basin from 2012 to 2021. The long-term measurements show that the subglacial lake was recharged by surface meltwater and that a rapid drainage event in late August 2019 induced an abrupt ice velocity change. Multiple factors regulate the episodic filling and drainage of the lake. Our study also reveals ~ 64 % of the surface meltwater successfully descended to the bed.
Anja Rutishauser, Donald D. Blankenship, Duncan A. Young, Natalie S. Wolfenbarger, Lucas H. Beem, Mark L. Skidmore, Ashley Dubnick, and Alison S. Criscitiello
The Cryosphere, 16, 379–395, https://doi.org/10.5194/tc-16-379-2022, https://doi.org/10.5194/tc-16-379-2022, 2022
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Recently, a hypersaline subglacial lake complex was hypothesized to lie beneath Devon Ice Cap, Canadian Arctic. Here, we present results from a follow-on targeted aerogeophysical survey. Our results support the evidence for a hypersaline subglacial lake and reveal an extensive brine network, suggesting more complex subglacial hydrological conditions than previously inferred. This hypersaline system may host microbial habitats, making it a compelling analog for bines on other icy worlds.
Amy Jenson, Jason M. Amundson, Jonathan Kingslake, and Eran Hood
The Cryosphere, 16, 333–347, https://doi.org/10.5194/tc-16-333-2022, https://doi.org/10.5194/tc-16-333-2022, 2022
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Outburst floods are sudden releases of water from glacial environments. As glaciers retreat, changes in glacier and basin geometry impact outburst flood characteristics. We combine a glacier flow model describing glacier retreat with an outburst flood model to explore how ice dam height, glacier length, and remnant ice in a basin influence outburst floods. We find storage capacity is the greatest indicator of flood magnitude, and the flood onset mechanism is a significant indicator of duration.
Anna Derkacheva, Fabien Gillet-Chaulet, Jeremie Mouginot, Eliot Jager, Nathan Maier, and Samuel Cook
The Cryosphere, 15, 5675–5704, https://doi.org/10.5194/tc-15-5675-2021, https://doi.org/10.5194/tc-15-5675-2021, 2021
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Along the edges of the Greenland Ice Sheet surface melt lubricates the bed and causes large seasonal fluctuations in ice speeds during summer. Accurately understanding how these ice speed changes occur is difficult due to the inaccessibility of the glacier bed. We show that by using surface velocity maps with high temporal resolution and numerical modelling we can infer the basal conditions that control seasonal fluctuations in ice speed and gain insight into seasonal dynamics over large areas.
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.
Matej Lipar, Andrea Martín-Pérez, Jure Tičar, Miha Pavšek, Matej Gabrovec, Mauro Hrvatin, Blaž Komac, Matija Zorn, Nadja Zupan Hajna, Jian-Xin Zhao, Russell N. Drysdale, and Mateja Ferk
The Cryosphere, 15, 17–30, https://doi.org/10.5194/tc-15-17-2021, https://doi.org/10.5194/tc-15-17-2021, 2021
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The U–Th ages of subglacial carbonate deposits from a recently exposed surface previously occupied by the disappearing glacier in the SE European Alps suggest the glacier’s presence throughout the entire Holocene. These thin deposits, formed by regelation, would have been easily eroded if exposed during previous Holocene climatic optima. The age data indicate the glacier’s present unprecedented level of retreat and the potential of subglacial carbonates to act as palaeoclimate proxies.
Andrew O. Hoffman, Knut Christianson, Daniel Shapero, Benjamin E. Smith, and Ian Joughin
The Cryosphere, 14, 4603–4609, https://doi.org/10.5194/tc-14-4603-2020, https://doi.org/10.5194/tc-14-4603-2020, 2020
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The West Antarctic Ice Sheet has long been considered geometrically prone to collapse, and Thwaites Glacier, the largest glacier in the Amundsen Sea, is likely in the early stages of disintegration. Using observations of Thwaites Glacier velocity and elevation change, we show that the transport of ~2 km3 of water beneath Thwaites Glacier has only a small and transient effect on glacier speed relative to ongoing thinning driven by ocean melt.
Felipe Napoleoni, Stewart S. R. Jamieson, Neil Ross, Michael J. Bentley, Andrés Rivera, Andrew M. Smith, Martin J. Siegert, Guy J. G. Paxman, Guisella Gacitúa, José A. Uribe, Rodrigo Zamora, Alex M. Brisbourne, and David G. Vaughan
The Cryosphere, 14, 4507–4524, https://doi.org/10.5194/tc-14-4507-2020, https://doi.org/10.5194/tc-14-4507-2020, 2020
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Subglacial water is important for ice sheet dynamics and stability. Despite this, there is a lack of detailed subglacial-water characterisation in West Antarctica (WA). We report 33 new subglacial lakes. Additionally, a new digital elevation model of basal topography was built and used to simulate the subglacial hydrological network in WA. The simulated subglacial hydrological catchments of Pine Island and Thwaites glaciers do not match precisely with their ice surface catchments.
Slawek M. Tulaczyk and Neil T. Foley
The Cryosphere, 14, 4495–4506, https://doi.org/10.5194/tc-14-4495-2020, https://doi.org/10.5194/tc-14-4495-2020, 2020
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Much of what we know about materials hidden beneath glaciers and ice sheets on Earth has been interpreted using radar reflection from the ice base. A common assumption is that electrical conductivity of the sub-ice materials does not influence the reflection strength and that the latter is controlled only by permittivity, which depends on the fraction of water in these materials. Here we argue that sub-ice electrical conductivity should be generally considered when interpreting radar records.
Andreas Alexander, Jaroslav Obu, Thomas V. Schuler, Andreas Kääb, and Hanne H. Christiansen
The Cryosphere, 14, 4217–4231, https://doi.org/10.5194/tc-14-4217-2020, https://doi.org/10.5194/tc-14-4217-2020, 2020
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In this study we present subglacial air, ice and sediment temperatures from within the basal drainage systems of two cold-based glaciers on Svalbard during late spring and the summer melt season. We put the data into the context of air temperature and rainfall at the glacier surface and show the importance of surface events on the subglacial thermal regime and erosion around basal drainage channels. Observed vertical erosion rates thereby reachup to 0.9 m d−1.
Alex Burton-Johnson, Ricarda Dziadek, and Carlos Martin
The Cryosphere, 14, 3843–3873, https://doi.org/10.5194/tc-14-3843-2020, https://doi.org/10.5194/tc-14-3843-2020, 2020
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The Antarctic ice sheet is the largest source for sea level rise. However, one key control on ice sheet flow remains poorly constrained: the effect of heat from the rocks beneath the ice sheet (known as
geothermal heat flow). Although this may not seem like a lot of heat, beneath thick, slow ice this heat can control how well the ice flows and can lead to melting of the ice sheet. We discuss the methods used to estimate this heat, compile existing data, and recommend future research.
Ugo Nanni, Florent Gimbert, Christian Vincent, Dominik Gräff, Fabian Walter, Luc Piard, and Luc Moreau
The Cryosphere, 14, 1475–1496, https://doi.org/10.5194/tc-14-1475-2020, https://doi.org/10.5194/tc-14-1475-2020, 2020
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Our study addresses key questions on the subglacial drainage system physics through a novel observational approach that overcomes traditional limitations. We conducted, over 2 years, measurements of the subglacial water-flow-induced seismic noise and of glacier basal sliding speeds. We then inverted for the subglacial channel's hydraulic pressure gradient and hydraulic radius and investigated the links between the equilibrium state of subglacial channels and glacier basal sliding.
Silje Smith-Johnsen, Basile de Fleurian, Nicole Schlegel, Helene Seroussi, and Kerim Nisancioglu
The Cryosphere, 14, 841–854, https://doi.org/10.5194/tc-14-841-2020, https://doi.org/10.5194/tc-14-841-2020, 2020
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The Northeast Greenland Ice Stream (NEGIS) drains a large part of Greenland and displays fast flow far inland. However, the flow pattern is not well represented in ice sheet models. The fast flow has been explained by abnormally high geothermal heat flux. The heat melts the base of the ice sheet and the water produced may lubricate the bed and induce fast flow. By including high geothermal heat flux and a hydrology model, we successfully reproduce NEGIS flow pattern in an ice sheet model.
Fabian Lindner, Fabian Walter, Gabi Laske, and Florent Gimbert
The Cryosphere, 14, 287–308, https://doi.org/10.5194/tc-14-287-2020, https://doi.org/10.5194/tc-14-287-2020, 2020
Michael A. Cooper, Thomas M. Jordan, Dustin M. Schroeder, Martin J. Siegert, Christopher N. Williams, and Jonathan L. Bamber
The Cryosphere, 13, 3093–3115, https://doi.org/10.5194/tc-13-3093-2019, https://doi.org/10.5194/tc-13-3093-2019, 2019
Edyta Łokas, Agata Zaborska, Ireneusz Sobota, Paweł Gaca, J. Andrew Milton, Paweł Kocurek, and Anna Cwanek
The Cryosphere, 13, 2075–2086, https://doi.org/10.5194/tc-13-2075-2019, https://doi.org/10.5194/tc-13-2075-2019, 2019
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Cryoconite granules built of mineral particles, organic substances and living organisms significantly influence fluxes of energy and matter at glacier surfaces. They contribute to ice melting, give rise to an exceptional ecosystem, and effectively trap contaminants. This study evaluates contamination levels of radionuclides in cryoconite from Arctic glaciers and identifies sources of this contamination, proving that cryoconite is an excellent indicator of atmospheric contamination.
Robert D. Larter, Kelly A. Hogan, Claus-Dieter Hillenbrand, James A. Smith, Christine L. Batchelor, Matthieu Cartigny, Alex J. Tate, James D. Kirkham, Zoë A. Roseby, Gerhard Kuhn, Alastair G. C. Graham, and Julian A. Dowdeswell
The Cryosphere, 13, 1583–1596, https://doi.org/10.5194/tc-13-1583-2019, https://doi.org/10.5194/tc-13-1583-2019, 2019
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We present high-resolution bathymetry data that provide the most complete and detailed imagery of any Antarctic palaeo-ice stream bed. These data show how subglacial water was delivered to and influenced the dynamic behaviour of the ice stream. Our observations provide insights relevant to understanding the behaviour of modern ice streams and forecasting the contributions that they will make to future sea level rise.
Benedict T. I. Reinardy, Adam D. Booth, Anna L. C. Hughes, Clare M. Boston, Henning Åkesson, Jostein Bakke, Atle Nesje, Rianne H. Giesen, and Danni M. Pearce
The Cryosphere, 13, 827–843, https://doi.org/10.5194/tc-13-827-2019, https://doi.org/10.5194/tc-13-827-2019, 2019
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Cold-ice processes may be widespread within temperate glacier systems but the role of cold-ice processes in temperate glacier systems is relatively unknown. Climate forcing is the main control on glacier mass balance but potential for heterogeneous thermal conditions at temperate glaciers calls for improved model assessments of future evolution of thermal conditions and impacts on glacier dynamics and mass balance. Cold-ice processes need to be included in temperate glacier land system models.
Joseph Graly, Joel Harrington, and Neil Humphrey
The Cryosphere, 11, 1131–1140, https://doi.org/10.5194/tc-11-1131-2017, https://doi.org/10.5194/tc-11-1131-2017, 2017
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At a major outlet of the Greenland Ice Sheet in West Greenland, we find that the chemical solutes in the emerging subglacial waters are out of phase with water discharge and can spike in concentration during waning flow. This suggests that the subglacial waters are spreading out across a large area of the glacial bed throughout the day, stimulating chemical weathering beyond the major water distribution channels.
Benjamin E. Smith, Noel Gourmelen, Alexander Huth, and Ian Joughin
The Cryosphere, 11, 451–467, https://doi.org/10.5194/tc-11-451-2017, https://doi.org/10.5194/tc-11-451-2017, 2017
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In this paper we investigate elevation changes of Thwaites Glacier, West Antarctica, one of the main sources of excess ice discharge into the ocean. We find that in early 2013, four subglacial lakes separated by 100 km drained suddenly, discharging more than 3 km3 of water under the fastest part of the glacier in less than 6 months. Concurrent ice-speed measurements show only minor changes, suggesting that ice dynamics are not strongly sensitive to changes in water flow.
Byeong-Hoon Kim, Choon-Ki Lee, Ki-Weon Seo, Won Sang Lee, and Ted Scambos
The Cryosphere, 10, 2971–2980, https://doi.org/10.5194/tc-10-2971-2016, https://doi.org/10.5194/tc-10-2971-2016, 2016
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Kamb Ice Stream (KIS) in Antarctica ceased rapid ice flow approximately 160 years ago, still influencing on the current mass balance of the West Antarctic Ice Sheet. We identify two previously unknown subglacial lakes beneath the stagnated trunk of the KIS. Rapid fill-drain hydrologic events over several months indicate that the lakes are probably connected by a subglacial drainage network. Our findings support previously published conceptual models of the KIS shutdown.
Maarten Krabbendam
The Cryosphere, 10, 1915–1932, https://doi.org/10.5194/tc-10-1915-2016, https://doi.org/10.5194/tc-10-1915-2016, 2016
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The way that ice moves over rough ground at the base of an ice sheet is important to understand and predict the behaviour of ice sheets. Here, I argue that if basal ice is at the melting temperature, as is locally the case below the Greenland Ice Sheet, this basal motion is easier and faster than hitherto thought. A thick (tens of metres) layer of ice at the melting temperature may better explain some ice streams and needs to be taken into account when modelling future ice sheet behaviour.
Takahiro Abe, Masato Furuya, and Daiki Sakakibara
The Cryosphere, 10, 1427–1432, https://doi.org/10.5194/tc-10-1427-2016, https://doi.org/10.5194/tc-10-1427-2016, 2016
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We identified 12-year cyclic surging episodes at Donjek Glacier in Yukon, Canada. The surging area is limited within the ~20km section from the terminus, originating in an area where the flow width significantly narrows downstream. Our results suggest strong control of the valley constriction on the surge dynamics.
B. P. Lipovsky and E. M. Dunham
The Cryosphere, 10, 385–399, https://doi.org/10.5194/tc-10-385-2016, https://doi.org/10.5194/tc-10-385-2016, 2016
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Small repeating earthquakes occur at the ice-bed interface of the Whillans Ice Stream, West Antarctica. The earthquakes occur as rapidly as 20 earthquakes/s. We conduct numerical simulations of these earthquakes that include elastic and frictional forces as well as seismic wave propagation. We create synthetic seismograms and compare these synthetics to observed seismograms in order to constrain subglacial parameters. We comment on decadal-scale changes in these parameters.
A. Damsgaard, D. L. Egholm, J. A. Piotrowski, S. Tulaczyk, N. K. Larsen, and C. F. Brædstrup
The Cryosphere, 9, 2183–2200, https://doi.org/10.5194/tc-9-2183-2015, https://doi.org/10.5194/tc-9-2183-2015, 2015
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This paper details a new algorithm for performing computational experiments of subglacial granular deformation. The numerical approach allows detailed studies of internal sediment and pore-water dynamics under shear. Feedbacks between sediment grains and pore water can cause rate-dependent strengthening, which additionally contributes to the plastic shear strength of the granular material. Hardening can stabilise patches of the subglacial beds with implications for landform development.
M. J. Siegert, N. Ross, H. Corr, B. Smith, T. Jordan, R. G. Bingham, F. Ferraccioli, D. M. Rippin, and A. Le Brocq
The Cryosphere, 8, 15–24, https://doi.org/10.5194/tc-8-15-2014, https://doi.org/10.5194/tc-8-15-2014, 2014
S. Goeller, M. Thoma, K. Grosfeld, and H. Miller
The Cryosphere, 7, 1095–1106, https://doi.org/10.5194/tc-7-1095-2013, https://doi.org/10.5194/tc-7-1095-2013, 2013
M. Thoma, K. Grosfeld, C. Mayer, A. M. Smith, J. Woodward, and N. Ross
The Cryosphere, 5, 561–567, https://doi.org/10.5194/tc-5-561-2011, https://doi.org/10.5194/tc-5-561-2011, 2011
M. Thoma, K. Grosfeld, C. Mayer, and F. Pattyn
The Cryosphere, 4, 1–12, https://doi.org/10.5194/tc-4-1-2010, https://doi.org/10.5194/tc-4-1-2010, 2010
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