Articles | Volume 14, issue 6
https://doi.org/10.5194/tc-14-1989-2020
© Author(s) 2020. 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-14-1989-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Jun 2020
Research article |
| 18 Jun 2020
| 18 Jun 2020
A quasi-annual record of time-transgressive esker formation: implications for ice-sheet reconstruction and subglacial hydrology
Stephen J. Livingstone
CORRESPONDING AUTHOR
Department of Geography, University of Sheffield, Sheffield, UK
Emma L. M. Lewington
Department of Geography, University of Sheffield, Sheffield, UK
Chris D. Clark
Department of Geography, University of Sheffield, Sheffield, UK
Robert D. Storrar
Department of the Natural and Built Environment, Sheffield Hallam
University, Sheffield, UK
Andrew J. Sole
Department of Geography, University of Sheffield, Sheffield, UK
Isabelle McMartin
Geological Survey of Canada, Natural Resources Canada, Ottawa, ON, Canada
Nico Dewald
Department of Geography, University of Sheffield, Sheffield, UK
Department of Geography, University of Sheffield, Sheffield, UK
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Jean Vérité, Édouard Ravier, Olivier Bourgeois, Stéphane Pochat, Thomas Lelandais, Régis Mourgues, Christopher D. Clark, Paul Bessin, David Peigné, and Nigel Atkinson
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Felix S. L. Ng
The Cryosphere, 15, 1787–1810, https://doi.org/10.5194/tc-15-1787-2021, https://doi.org/10.5194/tc-15-1787-2021, 2021
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Emma L. M. Lewington, Stephen J. Livingstone, Chris D. Clark, Andrew J. Sole, and Robert D. Storrar
The Cryosphere, 14, 2949–2976, https://doi.org/10.5194/tc-14-2949-2020, https://doi.org/10.5194/tc-14-2949-2020, 2020
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Adam J. Hepburn, Tom Holt, Bryn Hubbard, and Felix Ng
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Stephen J. Livingstone, Andrew J. Sole, Robert D. Storrar, Devin Harrison, Neil Ross, and Jade Bowling
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Niall Gandy, Lauren J. Gregoire, Jeremy C. Ely, Christopher D. Clark, David M. Hodgson, Victoria Lee, Tom Bradwell, and Ruza F. Ivanovic
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Thomas Lelandais, Édouard Ravier, Stéphane Pochat, Olivier Bourgeois, Christopher Clark, Régis Mourgues, and Pierre Strzerzynski
The Cryosphere, 12, 2759–2772, https://doi.org/10.5194/tc-12-2759-2018, https://doi.org/10.5194/tc-12-2759-2018, 2018
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Christopher N. Williams, Stephen L. Cornford, Thomas M. Jordan, Julian A. Dowdeswell, Martin J. Siegert, Christopher D. Clark, Darrel A. Swift, Andrew Sole, Ian Fenty, and Jonathan L. Bamber
The Cryosphere, 11, 363–380, https://doi.org/10.5194/tc-11-363-2017, https://doi.org/10.5194/tc-11-363-2017, 2017
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Stephen J. Livingstone and Chris D. Clark
Earth Surf. Dynam., 4, 567–589, https://doi.org/10.5194/esurf-4-567-2016, https://doi.org/10.5194/esurf-4-567-2016, 2016
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A. E. Jowett, E. Hanna, F. Ng, P. Huybrechts, and I. Janssens
The Cryosphere Discuss., https://doi.org/10.5194/tcd-9-5327-2015, https://doi.org/10.5194/tcd-9-5327-2015, 2015
Revised manuscript has not been submitted
S. de la Peña, I. M. Howat, P. W. Nienow, M. R. van den Broeke, E. Mosley-Thompson, S. F. Price, D. Mair, B. Noël, and A. J. Sole
The Cryosphere, 9, 1203–1211, https://doi.org/10.5194/tc-9-1203-2015, https://doi.org/10.5194/tc-9-1203-2015, 2015
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This paper presents an assessment of changes in the near-surface structure of the accumulation zone of the Greenland Ice Sheet caused by an increase of melt at higher elevations in the last decade, especially during the unusually warm years of 2010 and 2012. The increase in melt and firn densification complicate the interpretation of changes in the ice volume, and the observed increase in firn ice content may reduce the important meltwater buffering capacity of the Greenland Ice Sheet.
C. C. Clason, D. W. F. Mair, P. W. Nienow, I. D. Bartholomew, A. Sole, S. Palmer, and W. Schwanghart
The Cryosphere, 9, 123–138, https://doi.org/10.5194/tc-9-123-2015, https://doi.org/10.5194/tc-9-123-2015, 2015
N. Chauché, A. Hubbard, J.-C. Gascard, J. E. Box, R. Bates, M. Koppes, A. Sole, P. Christoffersen, and H. Patton
The Cryosphere, 8, 1457–1468, https://doi.org/10.5194/tc-8-1457-2014, https://doi.org/10.5194/tc-8-1457-2014, 2014
H. Patton, A. Hubbard, T. Bradwell, N. F. Glasser, M. J. Hambrey, and C. D. Clark
Earth Surf. Dynam., 1, 53–65, https://doi.org/10.5194/esurf-1-53-2013, https://doi.org/10.5194/esurf-1-53-2013, 2013
S. J. Livingstone, C. D. Clark, J. Woodward, and J. Kingslake
The Cryosphere, 7, 1721–1740, https://doi.org/10.5194/tc-7-1721-2013, https://doi.org/10.5194/tc-7-1721-2013, 2013
Related subject area
Discipline: Ice sheets | Subject: Geomorphology
Dynamical response of the southwestern Laurentide Ice Sheet to rapid Bølling–Allerød warming
Effects of topographic and meteorological parameters on the surface area loss of ice aprons in the Mont Blanc massif (European Alps)
Geomorphology and shallow sub-sea-floor structures underneath the Ekström Ice Shelf, Antarctica
Formation of ribbed bedforms below shear margins and lobes of palaeo-ice streams
Ice-stream flow switching by up-ice propagation of instabilities along glacial marginal troughs
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How dynamic are ice-stream beds?
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The Cryosphere, 18, 1533–1559, https://doi.org/10.5194/tc-18-1533-2024, https://doi.org/10.5194/tc-18-1533-2024, 2024
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Associated with climate change between the Last Glacial Maximum and the current interglacial period, we reconstruct the behaviour of the southwestern Laurentide Ice Sheet, which covered the Canadian Prairies, using detailed landform mapping. Our reconstruction depicts three shifts in the ice sheet’s dynamics. We suggest these changes resulted from ice sheet thinning triggered by abrupt climatic change. However, we show that regional lithology and topography also play an important role.
Suvrat Kaushik, Ludovic Ravanel, Florence Magnin, Yajing Yan, Emmanuel Trouve, and Diego Cusicanqui
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Climate change impacts all parts of the cryosphere but most importantly the smaller ice bodies like ice aprons (IAs). This study is the first attempt on a regional scale to assess the impacts of the changing climate on these small but very important ice bodies. Our study shows that IAs have consistently lost mass over the past decades. The effects of climate variables, particularly temperature and precipitation and topographic factors, were analysed on the loss of IA area.
Astrid Oetting, Emma C. Smith, Jan Erik Arndt, Boris Dorschel, Reinhard Drews, Todd A. Ehlers, Christoph Gaedicke, Coen Hofstede, Johann P. Klages, Gerhard Kuhn, Astrid Lambrecht, Andreas Läufer, Christoph Mayer, Ralf Tiedemann, Frank Wilhelms, and Olaf Eisen
The Cryosphere, 16, 2051–2066, https://doi.org/10.5194/tc-16-2051-2022, https://doi.org/10.5194/tc-16-2051-2022, 2022
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This study combines a variety of geophysical measurements in front of and beneath the Ekström Ice Shelf in order to identify and interpret geomorphological evidences of past ice sheet flow, extent and retreat.
The maximal extent of grounded ice in this region was 11 km away from the continental shelf break.
The thickness of palaeo-ice on the calving front around the LGM was estimated to be at least 305 to 320 m.
We provide essential boundary conditions for palaeo-ice-sheet models.
Jean Vérité, Édouard Ravier, Olivier Bourgeois, Stéphane Pochat, Thomas Lelandais, Régis Mourgues, Christopher D. Clark, Paul Bessin, David Peigné, and Nigel Atkinson
The Cryosphere, 15, 2889–2916, https://doi.org/10.5194/tc-15-2889-2021, https://doi.org/10.5194/tc-15-2889-2021, 2021
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Subglacial bedforms are commonly used to reconstruct past glacial dynamics and investigate processes occuring at the ice–bed interface. Using analogue modelling and geomorphological mapping, we demonstrate that ridges with undulating crests, known as subglacial ribbed bedforms, are ubiquitous features along ice stream corridors. These bedforms provide a tantalizing glimpse into (1) the former positions of ice stream margins, (2) the ice lobe dynamics and (3) the meltwater drainage efficiency.
Etienne Brouard and Patrick Lajeunesse
The Cryosphere, 13, 981–996, https://doi.org/10.5194/tc-13-981-2019, https://doi.org/10.5194/tc-13-981-2019, 2019
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Modifications in ice-stream networks have major impacts on ice sheet mass balance and global sea level. However, the mechanisms controlling ice-stream switching remain poorly understood. We report a flow switch in an ice-stream system that occurred on the Baffin Island shelf through the erosion of a marginal trough. Up-ice propagation of ice streams through marginal troughs can lead to the piracy of neighboring ice catchments, which induces an adjacent ice-stream switch and shutdown.
Josh Crozier, Leif Karlstrom, and Kang Yang
The Cryosphere, 12, 3383–3407, https://doi.org/10.5194/tc-12-3383-2018, https://doi.org/10.5194/tc-12-3383-2018, 2018
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Understanding ice sheet surface meltwater routing is important for modeling and predicting ice sheet evolution. We determined that bed topography underlying the Greenland Ice Sheet is the primary influence on 1–10 km scale ice surface topography, and on drainage-basin-scale surface meltwater routing. We provide a simple means of predicting the response of surface meltwater routing to changing ice flow conditions and explore the implications of this for subglacial hydrology.
Damon Davies, Robert G. Bingham, Edward C. King, Andrew M. Smith, Alex M. Brisbourne, Matteo Spagnolo, Alastair G. C. Graham, Anna E. Hogg, and David G. Vaughan
The Cryosphere, 12, 1615–1628, https://doi.org/10.5194/tc-12-1615-2018, https://doi.org/10.5194/tc-12-1615-2018, 2018
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This paper investigates the dynamics of ice stream beds using repeat geophysical surveys of the bed of Pine Island Glacier, West Antarctica; 60 km of the bed was surveyed, comprising the most extensive repeat ground-based geophysical surveys of an Antarctic ice stream; 90 % of the surveyed bed shows no significant change despite the glacier increasing in speed by up to 40 % over the last decade. This result suggests that ice stream beds are potentially more stable than previously suggested.
Anna Grau Galofre, A. Mark Jellinek, Gordon R. Osinski, Michael Zanetti, and Antero Kukko
The Cryosphere, 12, 1461–1478, https://doi.org/10.5194/tc-12-1461-2018, https://doi.org/10.5194/tc-12-1461-2018, 2018
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Water accumulated at the base of ice sheets is the main driver of glacier acceleration and loss of ice mass in Arctic regions. Previously glaciated landscapes sculpted by this water carry information about how ice sheets collapse and ultimately disappear. The search for these landscapes took us to the high Arctic, to explore channels that formed under kilometers of ice during the last ice age. In this work we describe how subglacial channels look and how they helped to drain an ice sheet.
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Short summary
We map series of aligned mounds (esker beads) across central Nunavut, Canada. Mounds are interpreted to have formed roughly annually as sediment carried by subglacial rivers is deposited at the ice margin. Chains of mounds are formed as the ice retreats. This high-resolution (annual) record allows us to constrain the pace of ice retreat, sediment fluxes, and the style of drainage through time. In particular, we suggest that eskers in general record a composite signature of ice-marginal drainage.
We map series of aligned mounds (esker beads) across central Nunavut, Canada. Mounds are...
