Articles | Volume 15, issue 2
https://doi.org/10.5194/tc-15-531-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-15-531-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Feb 2021
Research article |
| 03 Feb 2021
| 03 Feb 2021
A simple parametrization of mélange buttressing for calving glaciers
Tanja Schlemm
Potsdam Institute for Climate Impact Research, Potsdam, Germany
Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany
Anders Levermann
CORRESPONDING AUTHOR
Potsdam Institute for Climate Impact Research, Potsdam, Germany
Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany
Lamont-Doherty Earth Observatory, Columbia University, New York, USA
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Marine cliff instability, if it exists, could dominate Antarctica's contribution to future sea-level rise. It is likely to speed up with ice thickness and thus would accelerate in most parts of Antarctica. Here, we investigate a possible mechanism that might stop cliff instability through cloaking by ice mélange. It is only a first step, but it shows that embayment geometry is, in principle, able to stop marine cliff instability in most parts of West Antarctica.
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The Cryosphere Discuss., https://doi.org/10.5194/tc-2018-109, https://doi.org/10.5194/tc-2018-109, 2018
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Johannes Feldmann and Anders Levermann
The Cryosphere, 11, 1913–1932, https://doi.org/10.5194/tc-11-1913-2017, https://doi.org/10.5194/tc-11-1913-2017, 2017
Jacob Schewe and Anders Levermann
Earth Syst. Dynam., 8, 495–505, https://doi.org/10.5194/esd-8-495-2017, https://doi.org/10.5194/esd-8-495-2017, 2017
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Jan Wohland, Torsten Albrecht, and Anders Levermann
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In recent decades, the Greenland Ice Sheet has been losing mass and has thereby contributed to global sea-level rise. Here we derive the basic equations for the melt elevation feedback that can lead to self-amplifying melt of the Greenland Ice Sheet and ice sheets in general. The theory unifies the results of complex models when the feedback dominates the dynamics and it allows us to estimate the melt time of ice sheets from data in cases where ice dynamic loss can be neglected.
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J. Feldmann and A. Levermann
The Cryosphere, 9, 631–645, https://doi.org/10.5194/tc-9-631-2015, https://doi.org/10.5194/tc-9-631-2015, 2015
M. A. Martin, A. Levermann, and R. Winkelmann
The Cryosphere Discuss., https://doi.org/10.5194/tcd-9-1705-2015, https://doi.org/10.5194/tcd-9-1705-2015, 2015
Preprint withdrawn
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D. Ehlert and A. Levermann
Earth Syst. Dynam., 5, 383–397, https://doi.org/10.5194/esd-5-383-2014, https://doi.org/10.5194/esd-5-383-2014, 2014
A. Levermann, R. Winkelmann, S. Nowicki, J. L. Fastook, K. Frieler, R. Greve, H. H. Hellmer, M. A. Martin, M. Meinshausen, M. Mengel, A. J. Payne, D. Pollard, T. Sato, R. Timmermann, W. L. Wang, and R. A. Bindschadler
Earth Syst. Dynam., 5, 271–293, https://doi.org/10.5194/esd-5-271-2014, https://doi.org/10.5194/esd-5-271-2014, 2014
T. Albrecht and A. Levermann
The Cryosphere, 8, 587–605, https://doi.org/10.5194/tc-8-587-2014, https://doi.org/10.5194/tc-8-587-2014, 2014
C. F. Schleussner, J. Runge, J. Lehmann, and A. Levermann
Earth Syst. Dynam., 5, 103–115, https://doi.org/10.5194/esd-5-103-2014, https://doi.org/10.5194/esd-5-103-2014, 2014
A. Menon, A. Levermann, J. Schewe, J. Lehmann, and K. Frieler
Earth Syst. Dynam., 4, 287–300, https://doi.org/10.5194/esd-4-287-2013, https://doi.org/10.5194/esd-4-287-2013, 2013
Related subject area
Discipline: Ice sheets | Subject: Glaciers
Brief communication: Rapid acceleration of the Brunt Ice Shelf after calving of iceberg A-81
Geometric controls of tidewater glacier dynamics
A decade of variability on Jakobshavn Isbræ: ocean temperatures pace speed through influence on mélange rigidity
Oliver J. Marsh, Adrian J. Luckman, and Dominic A. Hodgson
The Cryosphere, 18, 705–710, https://doi.org/10.5194/tc-18-705-2024, https://doi.org/10.5194/tc-18-705-2024, 2024
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The Brunt Ice Shelf has accelerated rapidly after calving an iceberg in January 2023. A decade of GPS data show that the rate of acceleration in August 2023 was 30 times higher than before calving, and velocity has doubled in 6 months. Satellite velocity maps show the extent of the change. The acceleration is due to loss of contact between the ice shelf and a pinning point known as the McDonald Ice Rumples. The observations highlight how iceberg calving can directly impact ice shelves.
Thomas Frank, Henning Åkesson, Basile de Fleurian, Mathieu Morlighem, and Kerim H. Nisancioglu
The Cryosphere, 16, 581–601, https://doi.org/10.5194/tc-16-581-2022, https://doi.org/10.5194/tc-16-581-2022, 2022
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The shape of a fjord can promote or inhibit glacier retreat in response to climate change. We conduct experiments with a synthetic setup under idealized conditions in a numerical model to study and quantify the processes involved. We find that friction between ice and fjord is the most important factor and that it is possible to directly link ice discharge and grounding line retreat to fjord topography in a quantitative way.
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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Jakobshavn Isbræ, considered to be Greenland's fastest glacier, has varied its speed and thinned dramatically since the 1990s. Here we examine the glacier's behaviour over the last decade to better understand this behaviour. We find that when the floating ice (mélange) in front of the glacier freezes in place during the winter, it can control the glacier's speed and thinning rate. A recently colder ocean has strengthened this mélange, allowing the glacier to recoup some of its previous losses.
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Short summary
Ice loss from Greenland and Antarctica is often cloaked by a mélange of icebergs and sea ice. Here we provide a simple method to parametrize the resulting back stress on the ice flow for large-scale projection models.
Ice loss from Greenland and Antarctica is often cloaked by a mélange of icebergs and sea ice....
