Articles | Volume 15, issue 12
https://doi.org/10.5194/tc-15-5675-2021
© 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-15-5675-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Seasonal evolution of basal environment conditions of Russell sector, West Greenland, inverted from satellite observation of surface flow
Anna Derkacheva
CORRESPONDING AUTHOR
Institute of Environmental Geosciences, Université Grenoble Alpes, CNRS, IRD, INP, 38400 Grenoble, Isère, France
Fabien Gillet-Chaulet
Institute of Environmental Geosciences, Université Grenoble Alpes, CNRS, IRD, INP, 38400 Grenoble, Isère, France
Jeremie Mouginot
Institute of Environmental Geosciences, Université Grenoble Alpes, CNRS, IRD, INP, 38400 Grenoble, Isère, France
Department of Earth System Science, University of California, Irvine, 92697 CA, USA
Eliot Jager
Institute of Environmental Geosciences, Université Grenoble Alpes, CNRS, IRD, INP, 38400 Grenoble, Isère, France
Nathan Maier
Institute of Environmental Geosciences, Université Grenoble Alpes, CNRS, IRD, INP, 38400 Grenoble, Isère, France
Samuel Cook
Institute of Environmental Geosciences, Université Grenoble Alpes, CNRS, IRD, INP, 38400 Grenoble, Isère, France
Related authors
Romain Millan, Jeremie Mouginot, Anna Derkacheva, Eric Rignot, Pietro Milillo, Enrico Ciraci, Luigi Dini, and Anders Bjørk
The Cryosphere, 16, 3021–3031, https://doi.org/10.5194/tc-16-3021-2022, https://doi.org/10.5194/tc-16-3021-2022, 2022
Short summary
Short summary
We detect for the first time a dramatic retreat of the grounding line of Petermann Glacier, a major glacier of the Greenland Ice Sheet. Using satellite data, we also observe a speedup of the glacier and a fracturing of the ice shelf. This sequence of events is coherent with ocean warming in this region and suggests that Petermann Glacier has initiated a phase of destabilization, which is of prime importance for the stability and future contribution of the Greenland Ice Sheet to sea level rise.
Heiko Goelzer, Constantijn J. Berends, Fredrik Boberg, Gael Durand, Tamsin Edwards, Xavier Fettweis, Fabien Gillet-Chaulet, Quentin Glaude, Philippe Huybrechts, Sébastien Le clec'h, Ruth Mottram, Brice Noël, Martin Olesen, Charlotte Rahlves, Jeremy Rohmer, Michiel van den Broeke, and Roderik S. W. van de Wal
EGUsphere, https://doi.org/10.5194/egusphere-2025-3098, https://doi.org/10.5194/egusphere-2025-3098, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
We present an ensemble of ice sheet model projections for the Greenland ice sheet. The focus is on providing projections that improve our understanding of the range future sea-level rise and the inherent uncertainties over the next 100 to 300 years. Compared to earlier work we more fully account for some of the uncertainties in sea-level projections. We include a wider range of climate model output, more climate change scenarios and we extend projections schematically up to year 2300.
Cyrille Mosbeux, Peter Råback, Adrien Gilbert, Julien Brondex, Fabien Gillet-Chaulet, Nicolas C. Jourdain, Mondher Chekki, Olivier Gagliardini, and Gaël Durand
EGUsphere, https://doi.org/10.5194/egusphere-2025-3039, https://doi.org/10.5194/egusphere-2025-3039, 2025
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
Short summary
Short summary
Transport processes like rocks carried by ice flow and damage evolution – a proxy for crevasses – are key in ice sheet modeling and should occur without diffusion. Yet, standard numerical methods often blur these features. We explore a particle-based Semi-Lagrangian approach, comparing it to a Discontinuous Galerkin method, and show it can accurately simulate such transport when run at high enough resolution.
Davor Dundovic, Joseph G. Wallwork, Stephan C. Kramer, Fabien Gillet-Chaulet, Regine Hock, and Matthew D. Piggott
Geosci. Model Dev., 18, 4023–4044, https://doi.org/10.5194/gmd-18-4023-2025, https://doi.org/10.5194/gmd-18-4023-2025, 2025
Short summary
Short summary
Accurate numerical studies of glaciers often require high-resolution simulations, which often prove too demanding even for modern computers. In this paper we develop a method that identifies whether different parts of a glacier require high or low resolution based on its physical features, such as its thickness and velocity. We show that by doing so we can achieve a more optimal simulation accuracy for the available computing resources compared to uniform-resolution simulations.
Justine Caillet, Nicolas C. Jourdain, Pierre Mathiot, Fabien Gillet-Chaulet, Benoit Urruty, Clara Burgard, Charles Amory, Mondher Chekki, and Christoph Kittel
Earth Syst. Dynam., 16, 293–315, https://doi.org/10.5194/esd-16-293-2025, https://doi.org/10.5194/esd-16-293-2025, 2025
Short summary
Short summary
Internal climate variability, resulting from processes intrinsic to the climate system, modulates the Antarctic response to climate change by delaying or offsetting its effects. Using climate and ice-sheet models, we highlight that irreducible internal climate variability significantly enlarges the likely range of Antarctic contribution to sea-level rise until 2100. Thus, we recommend considering internal climate variability as a source of uncertainty for future ice-sheet projections.
Juan-Pedro Roldán-Blasco, Adrien Gilbert, Luc Piard, Florent Gimbert, Christian Vincent, Olivier Gagliardini, Anuar Togaibekov, Andrea Walpersdorf, and Nathan Maier
The Cryosphere, 19, 267–282, https://doi.org/10.5194/tc-19-267-2025, https://doi.org/10.5194/tc-19-267-2025, 2025
Short summary
Short summary
The flow of glaciers and ice sheets results from ice deformation and basal sliding driven by gravitational forces. Quantifying the rate at which ice deforms under its own weight is critical for assessing glacier evolution. This study uses borehole instrumentation in an Alpine glacier to quantify ice deformation and constrain ice viscosity in a natural setting. Our results show that the viscosity of ice at 0 °C is largely influenced by interstitial liquid water, which enhances ice deformation.
Eliot Jager, Fabien Gillet-Chaulet, Nicolas Champollion, Romain Millan, Heiko Goelzer, and Jérémie Mouginot
The Cryosphere, 18, 5519–5550, https://doi.org/10.5194/tc-18-5519-2024, https://doi.org/10.5194/tc-18-5519-2024, 2024
Short summary
Short summary
Inspired by a previous intercomparison framework, our study better constrains uncertainties in glacier evolution using an innovative method to validate Bayesian calibration. Upernavik Isstrøm, one of Greenland's largest glaciers, has lost significant mass since 1985. By integrating observational data, climate models, human emissions, and internal model parameters, we project its evolution until 2100. We show that future human emissions are the main source of uncertainty in 2100, making up half.
Emily A. Hill, Benoît Urruty, Ronja Reese, Julius Garbe, Olivier Gagliardini, Gaël Durand, Fabien Gillet-Chaulet, G. Hilmar Gudmundsson, Ricarda Winkelmann, Mondher Chekki, David Chandler, and Petra M. Langebroek
The Cryosphere, 17, 3739–3759, https://doi.org/10.5194/tc-17-3739-2023, https://doi.org/10.5194/tc-17-3739-2023, 2023
Short summary
Short summary
The grounding lines of the Antarctic Ice Sheet could enter phases of irreversible retreat or advance. We use three ice sheet models to show that the present-day locations of Antarctic grounding lines are reversible with respect to a small perturbation away from their current position. This indicates that present-day retreat of the grounding lines is not yet irreversible or self-enhancing.
Ronja Reese, Julius Garbe, Emily A. Hill, Benoît Urruty, Kaitlin A. Naughten, Olivier Gagliardini, Gaël Durand, Fabien Gillet-Chaulet, G. Hilmar Gudmundsson, David Chandler, Petra M. Langebroek, and Ricarda Winkelmann
The Cryosphere, 17, 3761–3783, https://doi.org/10.5194/tc-17-3761-2023, https://doi.org/10.5194/tc-17-3761-2023, 2023
Short summary
Short summary
We use an ice sheet model to test where current climate conditions in Antarctica might lead. We find that present-day ocean and atmosphere conditions might commit an irreversible collapse of parts of West Antarctica which evolves over centuries to millennia. Importantly, this collapse is not irreversible yet.
Inès N. Otosaka, Andrew Shepherd, Erik R. Ivins, Nicole-Jeanne Schlegel, Charles Amory, Michiel R. van den Broeke, Martin Horwath, Ian Joughin, Michalea D. King, Gerhard Krinner, Sophie Nowicki, Anthony J. Payne, Eric Rignot, Ted Scambos, Karen M. Simon, Benjamin E. Smith, Louise S. Sørensen, Isabella Velicogna, Pippa L. Whitehouse, Geruo A, Cécile Agosta, Andreas P. Ahlstrøm, Alejandro Blazquez, William Colgan, Marcus E. Engdahl, Xavier Fettweis, Rene Forsberg, Hubert Gallée, Alex Gardner, Lin Gilbert, Noel Gourmelen, Andreas Groh, Brian C. Gunter, Christopher Harig, Veit Helm, Shfaqat Abbas Khan, Christoph Kittel, Hannes Konrad, Peter L. Langen, Benoit S. Lecavalier, Chia-Chun Liang, Bryant D. Loomis, Malcolm McMillan, Daniele Melini, Sebastian H. Mernild, Ruth Mottram, Jeremie Mouginot, Johan Nilsson, Brice Noël, Mark E. Pattle, William R. Peltier, Nadege Pie, Mònica Roca, Ingo Sasgen, Himanshu V. Save, Ki-Weon Seo, Bernd Scheuchl, Ernst J. O. Schrama, Ludwig Schröder, Sebastian B. Simonsen, Thomas Slater, Giorgio Spada, Tyler C. Sutterley, Bramha Dutt Vishwakarma, Jan Melchior van Wessem, David Wiese, Wouter van der Wal, and Bert Wouters
Earth Syst. Sci. Data, 15, 1597–1616, https://doi.org/10.5194/essd-15-1597-2023, https://doi.org/10.5194/essd-15-1597-2023, 2023
Short summary
Short summary
By measuring changes in the volume, gravitational attraction, and ice flow of Greenland and Antarctica from space, we can monitor their mass gain and loss over time. Here, we present a new record of the Earth’s polar ice sheet mass balance produced by aggregating 50 satellite-based estimates of ice sheet mass change. This new assessment shows that the ice sheets have lost (7.5 x 1012) t of ice between 1992 and 2020, contributing 21 mm to sea level rise.
Romain Millan, Jeremie Mouginot, Anna Derkacheva, Eric Rignot, Pietro Milillo, Enrico Ciraci, Luigi Dini, and Anders Bjørk
The Cryosphere, 16, 3021–3031, https://doi.org/10.5194/tc-16-3021-2022, https://doi.org/10.5194/tc-16-3021-2022, 2022
Short summary
Short summary
We detect for the first time a dramatic retreat of the grounding line of Petermann Glacier, a major glacier of the Greenland Ice Sheet. Using satellite data, we also observe a speedup of the glacier and a fracturing of the ice shelf. This sequence of events is coherent with ocean warming in this region and suggests that Petermann Glacier has initiated a phase of destabilization, which is of prime importance for the stability and future contribution of the Greenland Ice Sheet to sea level rise.
L. Charrier, Y. Yan, E. Colin Koeniguer, J. Mouginot, R. Millan, and E. Trouvé
ISPRS Ann. Photogramm. Remote Sens. Spatial Inf. Sci., V-3-2022, 311–318, https://doi.org/10.5194/isprs-annals-V-3-2022-311-2022, https://doi.org/10.5194/isprs-annals-V-3-2022-311-2022, 2022
Nathan Maier, Florent Gimbert, Fabien Gillet-Chaulet, and Adrien Gilbert
The Cryosphere, 15, 1435–1451, https://doi.org/10.5194/tc-15-1435-2021, https://doi.org/10.5194/tc-15-1435-2021, 2021
Short summary
Short summary
In Greenland, ice motion and the surface geometry depend on the friction at the bed. We use satellite measurements and modeling to determine how ice speeds and friction are related across the ice sheet. The relationships indicate that ice flowing over bed bumps sets the friction across most of the ice sheet's on-land regions. This result helps simplify and improve our understanding of how ice motion will change in the future.
Vincent Peyaud, Coline Bouchayer, Olivier Gagliardini, Christian Vincent, Fabien Gillet-Chaulet, Delphine Six, and Olivier Laarman
The Cryosphere, 14, 3979–3994, https://doi.org/10.5194/tc-14-3979-2020, https://doi.org/10.5194/tc-14-3979-2020, 2020
Short summary
Short summary
Alpine glaciers are retreating at an accelerating rate in a warming climate. Numerical models allow us to study and anticipate these changes, but the performance of a model is difficult to evaluate. So we compared an ice flow model with the long dataset of observations obtained between 1979 and 2015 on Mer de Glace (Mont Blanc area). The model accurately reconstructs the past evolution of the glacier. We simulate the future evolution of Mer de Glace; it could retreat by 2 to 6 km by 2050.
Cited articles
Ahlstrøm, A. P., Petersen, D., Langen, P. L., Citterio, M., and Box, J. E.: Abrupt shift in the observed runoff from the southwestern Greenland ice
sheet, Sci. Adv., 3, 1–8, https://doi.org/10.1126/sciadv.1701169, 2017. a
Altena, B. and Kääb, A.: Weekly glacier flow estimation from dense
satellite time series using adapted optical flow technology, Front. Earth Sci., 5, 1–12, https://doi.org/10.3389/feart.2017.00053, 2017. a
Arthern, R. J. and Gudmundsson, G. H.: Initialization of ice-sheet forecasts
viewed as an inverse Robin problem, J. Glaciol., 56, 527–533,
https://doi.org/10.3189/002214310792447699, 2010. a, b
Arthern, R. J., Hindmarsh, R. C. A., and Williams, C. R.: Flow speed within
the Antarctic ice sheet and its controls inferred from satellite observations, J. Geophys. Res.-Earth, 120, 1171–1188, https://doi.org/10.1002/2014JF003239, 2015. a
Bartholomew, I., Nienow, P., Mair, D., Hubbard, A., King, M. A., and Sole, A.: Seasonal evolution of subglacial drainage and acceleration in a Greenland
outlet glacier, Nat. Geosci., 3, 408–411, https://doi.org/10.1038/ngeo863, 2010. a, b, c
Bartholomew, I., Nienow, P., Sole, A., Mair, D., Cowton, T., and King, M. A.:
Short-term variability in Greenland Ice Sheet motion forced by time-varying
meltwater drainage: Implications for the relationship between subglacial
drainage system behavior and ice velocity, J. Geophys. Res.-Earth, 117, 1–17, https://doi.org/10.1029/2011JF002220, 2012. a
Booth, A. D., Clark, R. A., Kulessa, B., Murray, T., Carter, J., Doyle, S., and Hubbard, A.: Thin-layer effects in glaciological seismic
amplitude-versus-angle (AVA) analysis: implications for characterising a
subglacial till unit, Russell Glacier, West Greenland, The Cryosphere, 6,
909–922, https://doi.org/10.5194/tc-6-909-2012, 2012. a
Bougamont, M., Christoffersen, P., Hubbard, A. L., Fitzpatrick, A. A., Doyle,
S. H., and Carter, S. P.:Sensitive response of the Greenland Ice Sheet to
surface melt drainage over a soft bed, Nat. Commun., 5, 5052, https://doi.org/10.1038/ncomms6052, 2014. a, b, c, d
Box, J. E., Fettweis, X., Stroeve, J. C., Tedesco, M., Hall, D. K., and Steffen, K.: Greenland ice sheet albedo feedback: thermodynamics and atmospheric drivers, The Cryosphere, 6, 821–839, https://doi.org/10.5194/tc-6-821-2012, 2012. a
Brinkerhoff, D., Aschwanden, A., and Fahnestock, M.: Constraining subglacial
processes from surface velocity observations using surrogate-based Bayesian
inference, J. Glaciol., 67, 385–403, https://doi.org/10.1017/jog.2020.112, 2021. a, b
Budd, W. F., Keage, P., and Blundy, N.: Empirical study of ice sliding, J. Glaciol., 2, 157–170, https://doi.org/10.3189/S0022143000029804, 1979. a
Budd, W. F., Jenssen, D., and Smith, I. N.: A Three-Dimensional Time-Dependent Model of the West Antarctic Ice Sheet, Ann. Glaciol., 5, 29–36, https://doi.org/10.3189/1984AoG5-1-29-36, 1984. a
Cabral, B. and Leedom, L. C.: Imaging Vector Fields Using Line Integral
Convolution, in: Proceedings of ACM SIGGRAPH'93, Anaheim, 263–270, https://doi.org/10.1145/166117.166151, 1993. a
Christoffersen, P., Bougamont, M., Hubbard, A., Doyle, S. H., Grigsby, S., and Pettersson, R.: Cascading lake drainage on the Greenland Ice Sheet triggered by tensile shock and fracture, Nat. Commun., 9, 1064,
https://doi.org/10.1038/s41467-018-03420-8, 2018. a, b
Cleveland, W. S.: Robust locally weighted regression and smoothing
scatterplots, J. Am. Stat. Assoc., 74, 829–836, https://doi.org/10.1080/01621459.1979.10481038, 1979. a
Cleveland, W. S. and Devlin, S. J.: Locally weighted regression: An approach
to regression analysis by local fitting, J. Am. Stat. Assoc., 83, 596–610, https://doi.org/10.1080/01621459.1988.10478639, 1988. a
Cook, S. J., Christoffersen, P., Todd, J., Slater, D., and Chauché, N.: Coupled modelling of subglacial hydrology and calving-front melting at Store Glacier, West Greenland, The Cryosphere, 14, 905–924, https://doi.org/10.5194/tc-14-905-2020, 2020. a, b, c
Cook, S. J., Christoffersen, P., and Todd, J.: A fully-coupled 3D model of a
large Greenlandic outlet glacier with evolving subglacial hydrology, frontal
plume melting and calving, J. Glaciol., https://doi.org/10.1017/jog.2021.109, in press, 2021. a
Cowton, T., Sole, A., Nienow, P., Slater, D., Wilton, D., and Hanna, E.:
Controls on the transport of oceanic heat to Kangerdlugssuaq Glacier, East
Greenland, J. Glaciol., 62, 1167–1180, https://doi.org/10.1017/jog.2016.117, 2016. a
Csatho, B. M., Schenka, A. F., Van Der Veen, C. J., Babonis, G., Duncan, K.,
Rezvanbehbahani, S., Van Den Broeke, M. R., Simonsen, S. B., Nagarajan, S.,
and Van Angelen, J. H.: Laser altimetry reveals complex pattern of Greenland Ice Sheet dynamics, P. Natl. Acad. Sci. USA, 111, 18478–18483,
https://doi.org/10.1073/pnas.1411680112, 2014. a
Cuffey, K. and Paterson, W.: The physics of glaciers, Academic Press, Amsterdam, 2010. a
Dapogny, C., Dobrzynski, C., and Frey, P.: Three-dimensional adaptive domain
remeshing, implicit domain meshing, and applications to free and moving
boundary problems, J. Comput. Phys., 262, 358–378, https://doi.org/10.1016/j.jcp.2014.01.005, 2014. a
Davison, B. J., Sole, A. J., Livingstone, S. J., Cowton, T. R., and Nienow, P. W.: The Influence of Hydrology on the Dynamics of Land-Terminating
Sectors of the Greenland Ice Sheet, Front. Earth Sci., 7, 1–24,
https://doi.org/10.3389/feart.2019.00010, 2019. a, b, c, d
de Fleurian, B., Morlighem, M., Seroussi, H., Rignot, E., van den Broeke,
M. R., Kuipers Munneke, P., Mouginot, J., Smeets, P. C. J. P., and Tedstone, A. J.: A modeling study of the effect of runoff variability on the effective pressure beneath Russell Glacier, West Greenland, J. Geophys. Res.-Earth, 121, 1834–1848, https://doi.org/10.1002/2016JF003842, 2016. a, b, c, d, e
De Fleurian, B., Werder, M. A., Beyer, S., Brinkerhoff, D. J., Delaney, I.,
Dow, C. F., Downs, J., Gagliardini, O., Hoffman, M. J., Hooke, R. L.,
Seguinot, J., and Sommers, A. N.: SHMIP the subglacial hydrology model
intercomparison Project, J. Glaciology, 64, 897–916, https://doi.org/10.1017/jog.2018.78, 2018. a
Derkacheva, A., Mouginot, J., Millan, R., Maier, N., and Gillet-Chaulet, F.:
Data Reduction Using Statistical and Regression Approaches for Ice Velocity
Derived by Landsat-8, Sentinel-1 and Sentinel-2, Remote Sens., 12, 1935,
https://doi.org/10.3390/rs12121935, 2020. a, b, c
Derkacheva, A., Mouginot, J., and Millan, R.: Satellite-observed surface flow speed within Russell sector, West Greenland, bi-weekly average of 2015–2019 (1.0), Zenodo [data set], https://doi.org/10.5281/zenodo.5535532, 2021a. a
Derkacheva, A., Gillet-Chaulet, F., and Mouginot, J.: Seasonal evolution of basal conditions within Russell sector, West Greenland, inverted from satellite observations of surface flow (1.0), Zenodo [data set], https://doi.org/10.5281/zenodo.5535624, 2021b. a
Doyle, S. H., Hubbard, A., Van De Wal, R. S., Box, J. E., Van As, D., Scharrer, K., Meierbachtol, T. W., Smeets, P. C., Harper, J. T., Johansson, E., Mottram, R. H., Mikkelsen, A. B., Wilhelms, F., Patton, H., Christoffersen, P., and Hubbard, B.: Amplified melt and flow of the Greenland ice sheet driven by late-summer cyclonic rainfall, Nat. Geosci., 8, 647–653, https://doi.org/10.1038/ngeo2482, 2015. a
Edwards, T. L., Fettweis, X., Gagliardini, O., Gillet-Chaulet, F., Goelzer, H., Gregory, J. M., Hoffman, M., Huybrechts, P., Payne, A. J., Perego, M., Price, S., Quiquet, A., and Ritz, C.: Effect of uncertainty in surface mass
balance-elevation feedback on projections of the future sea level
contribution of the Greenland ice sheet, The Cryosphere, 8, 195–208,
https://doi.org/10.5194/tc-8-195-2014, 2014. a
Elmer/Ice: Open Source Finite Element Software for Ice Sheet, Glaciers and Ice Flow Modelling, Elmer/Ice [code], http://elmerice.elmerfem.org/, last access: 21 February 2020. a
Fahnestock, M., Scambos, T., Moon, T., Gardner, A., Haran, T., and Klinger, M.: Rapid large-area mapping of ice flow using Landsat 8, Remote Sens. Environ., 185, 84–94, https://doi.org/10.1016/j.rse.2015.11.023, 2016. a
Fettweis, X., Hofer, S., Krebs-Kanzow, U., Amory, C., Aoki, T., Berends, C. J., Born, A., Box, J. E., Delhasse, A., Fujita, K., Gierz, P., Goelzer, H., Hanna, E., Hashimoto, A., Huybrechts, P., Kapsch, M.-L., King, M. D., Kittel, C., Lang, C., Langen, P. L., Lenaerts, J. T. M., Liston, G. E., Lohmann, G., Mernild, S. H., Mikolajewicz, U., Modali, K., Mottram, R. H., Niwano, M., Noël, B., Ryan, J. C., Smith, A., Streffing, J., Tedesco, M., van de Berg, W. J., van den Broeke, M., van de Wal, R. S. W., van Kampenhout, L., Wilton, D., Wouters, B., Ziemen, F., and Zolles, T.: GrSMBMIP: intercomparison of the modelled 1980–2012 surface mass balance over the Greenland Ice Sheet, The Cryosphere, 14, 3935–3958, https://doi.org/10.5194/tc-14-3935-2020, 2020. a
Fitzpatrick, A. A., Hubbard, A., Joughin, I., Quincey, D. J., As, D. V.,
Mikkelsen, A. P., Doyle, S. H., Hasholt, B., and Jones, G. A.: Ice flow
dynamics and surface meltwater flux at a land-terminating sector of the
Greenland ice sheet, J. Glaciol., 59, 687–696, https://doi.org/10.3189/2013JoG12J143, 2013. a, b
Flowers, G. E.: Modelling water flow under glaciers and ice sheets, P. Roy. Soc. A, 471, 20140907, https://doi.org/10.1098/rspa.2014.0907, 2015. a
Fountain, A. G. and Walder, J. S.: Water flow through temperate glaciers, Rev. Geophys., 36, 299–328, https://doi.org/10.1029/97RG03579, 1998. a
Fowler, A. C.: On the rheology of till, Ann. Glaciol., 37, 55–59,
https://doi.org/10.3189/172756403781815951, 2003. a
Gagliardini, O. and Meyssonnier, J.: Lateral boundary conditions for a local
anisotropic ice-flow model, Ann. Glaciol., 35, 503–509, https://doi.org/10.3189/172756402781817202, 2002. a
Gagliardini, O. and Werder, M. A.: Influence of increasing surface melt over
decadal timescales on land-terminating Greenland-type outlet glaciers, J. Glaciol., 64, 700–710, https://doi.org/10.1017/jog.2018.59, 2018. a, b, c, d
Gagliardini, O., Cohen, D., Råback, P., and Zwinger, T.: Finite-element
modeling of subglacial cavities and related friction law, J. Geophys. Res., 112, F02027, https://doi.org/10.1029/2006JF000576, 2007. a, b, c, d
Gagliardini, O., Zwinger, T., Gillet-Chaulet, F., Durand, G., Favier, L.,
de Fleurian, B., Greve, R., Malinen, M., Martín, C., Råback, P.,
Ruokolainen, J., Sacchettini, M., Schäfer, M., Seddik, H., and Thies, J.: Capabilities and performance of Elmer/Ice, a new-generation ice sheet model, Geosci. Model Dev., 6, 1299–1318, https://doi.org/10.5194/gmd-6-1299-2013, 2013. a, b, c
Gilbert, J. C. and Lemaréchal, C.: Some numerical experiments with
variable-storage quasi-Newton algorithms, Math. Program., 45, 407–435, https://doi.org/10.1007/BF01589113, 1989. a
Gillet-Chaulet, F., Gagliardini, O., Seddik, H., Nodet, M., Durand, G., Ritz,
C., Zwinger, T., Greve, R., and Vaughan, D. G.: Greenland ice sheet
contribution to sea-level rise from a new-generation ice-sheet model, The Cryosphere, 6, 1561–1576, https://doi.org/10.5194/tc-6-1561-2012, 2012. a
Gillet-Chaulet, F., Durand, G., Gagliardini, O., Mosbeux, C., Mouginot, J.,
Rémy, F., and Ritz, C.: Assimilation of surface velocities acquired
between 1996 and 2010 to constrain the form of the basal friction law under
Pine Island Glacier, Geophys. Res. Lett., 43, 10311–10321,
https://doi.org/10.1002/2016GL069937, 2016. a
Goelzer, H., Robinson, A., Seroussi, H., and van de Wal, R. S.: Recent
Progress in Greenland Ice Sheet Modelling, Curr. Clim. Change Rep., 3, 291–302, https://doi.org/10.1007/s40641-017-0073-y, 2017. a
Goelzer, H., Nowicki, S., Payne, A., Larour, E., Seroussi, H., Lipscomb, W. H., Gregory, J., Abe-Ouchi, A., Shepherd, A., Simon, E., Agosta, C., Alexander, P., Aschwanden, A., Barthel, A., Calov, R., Chambers, C., Choi, Y., Cuzzone, J., Dumas, C., Edwards, T., Felikson, D., Fettweis, X., Golledge, N. R., Greve, R., Humbert, A., Huybrechts, P., Le Clec'h, S., Lee, V., Leguy, G., Little, C., Lowry, D., Morlighem, M., Nias, I., Quiquet, A., Rückamp, M., Schlegel, N. J., Slater, D. A., Smith, R., Straneo, F., Tarasov, L., Van De Wal, R., and Van Den Broeke, M.: The future sea-level contribution of the Greenland ice sheet: A multi-model ensemble study of ISMIP6, The Cryosphere, 14, 3071–3096, https://doi.org/10.5194/tc-14-3071-2020, 2020. a, b
Greskowiak, J.: Tide-induced salt-fingering flow during submarine groundwater
discharge, Geophys. Res. Lett., 41, 6413–6419, https://doi.org/10.1002/2014GL061184, 2014. a, b, c
Habermann, M., Maxwell, D., and Truffer, M.: Reconstruction of basal properties in ice sheets using iterative inverse methods, J. Glaciol., 58, 795–807, https://doi.org/10.3189/2012JoG11J168, 2012. a
Habermann, M., Truffer, M., and Maxwell, D.: Error sources in basal yield
stress inversions for Jakobshavn Isbræ, Greenland, derived from residual
patterns of misfit to observations, J. Glaciol., 63, 999–1011,
https://doi.org/10.1017/jog.2017.61, 2017. a
Hansen, P. C.: The L-Curve and its Use in the Numerical Treatment of Inverse Problems, in: Computational Inverse Problems in Electrocardiology, edited by: Johnston, P., WIT Press, 119–142, 2001. a
Harper, J., Meierbachtol, T., Humphrey, N., Saito, J., and Stansberry, A.: Variability of Basal Meltwater Generation During Winter, Western Greenland Ice Sheet, The Cryosphere Discuss. [preprint], https://doi.org/10.5194/tc-2021-179, in review, 2021. a
Harper, J. T., Humphrey, N. F., Meierbachtol, T. W., Graly, J. A., and Fischer, U. H.: Borehole measurements indicate hard bed conditions, Kangerlussuaq sector, western Greenland Ice Sheet, J. Geophys. Res.-Earth,
122, 1605–1618, https://doi.org/10.1002/2017JF004201, 2017. a, b, c, d
Harrington, J. A., Humphrey, N. F., and Harper, J. T.: Temperature distribution and thermal anomalies along a flowline of the Greenland ice
sheet, Ann. Glaciol., 56, 98–104, https://doi.org/10.3189/2015AoG70A945, 2015. a, b, c, d
Helanow, C., Iverson, N. R., Woodard, J. B., and Zoet, L. K.: A slip law for
hard-bedded glaciers derived from observed bed topography, Sci. Adv., 7, eabe7798, https://doi.org/10.1126/sciadv.abe7798, 2021. a
Helm, V., Humbert, A., and Miller, H.: Elevation and elevation change of
Greenland and Antarctica derived from CryoSat-2, The Cryosphere, 8, 1539–1559, https://doi.org/10.5194/tc-8-1539-2014, 2014. a
Hills, B. H., Harper, J. T., Humphrey, N. F., and Meierbachtol, T. W.:
Measured Horizontal Temperature Gradients Constrain Heat Transfer Mechanisms
in Greenland Ice, Geophys. Res. Lett., 44, 9778–9785, https://doi.org/10.1002/2017GL074917, 2017. a, b, c, d
Hoffman, M. J., Andrews, L. C., Price, S. A., Catania, G. A., Neumann, T. A.,
Lüthi, M. P., Gulley, J., Ryser, C., Hawley, R. L., and Morriss, B.:
Greenland subglacial drainage evolution regulated by weakly connected regions of the bed, Nat. Commun., 7, 13903, https://doi.org/10.1038/ncomms13903, 2016. a, b, c
Howat, I., Negrete, A., and Smith, B.: MEaSUREs Greenland Ice Mapping Project (GIMP) Digital Elevation Model (2.1), NASA National Snow and Ice Data Center Distributed Active Archive Center, Boulder, Colorado, USA, [data set], https://doi.org/10.5067/NV34YUIXLP9W, 2015. a
Howat, I. M., Negrete, A., and Smith, B. E.: The Greenland Ice Mapping Project (GIMP) land classification and surface elevation data sets, The Cryosphere, 8, 1509–1518, https://doi.org/10.5194/tc-8-1509-2014, 2014. a, b
Iken, A.: The effect of the subglacial water pressure on the sliding velocity
of a glacier in an idealized numerical model, J. Glaciol., 27, 407–421, https://doi.org/10.1017/S0022143000011448, 1981. a, b, c
Iverson, N. R.: Shear resistance and continuity of subglacial till: Hydrology
rules, J. Glaciol., 56, 1104–1114, https://doi.org/10.3189/002214311796406220, 2011. a
Iverson, N. R., Hooyer, T. S., and Baker, R. W.: Ring-shear studies of till
deformation: Coulomb-plastic behavior and distributed strain in glacier
beds, J. Glaciol., 44, 634–642, https://doi.org/10.1017/S0022143000002136, 1998. a, b
Jay-Allemand, M., Gillet-Chaulet, F., Gagliardini, O., and Nodet, M.:
Investigating changes in basal conditions of Variegated Glacier prior to and
during its 1982–1983 surge, The Cryosphere, 5, 659–672,
https://doi.org/10.5194/tc-5-659-2011, 2011. a, b, c
Joughin, I., MacAyeal, D. R., and Tulaczyk, S.: Basal shear stress of the Ross ice streams from control method inversions, J. Geophys. Res.-Solid, 109, 1–20, https://doi.org/10.1029/2003JB002960, 2004. a
Joughin, I., Das, S. B., King, M. A., Smith, B. E., and Howat, I. M.: Seasonal Speedup Along the Western Flank of the Greenland Ice Sheet, Science, 320, 781–783, 2008. a
Joughin, I., Smith, B. E., and Howat, I.: Greenland Ice Mapping Project: ice
flow velocity variation at sub-monthly to decadal timescales, The Cryosphere, 12, 2211–2227, https://doi.org/10.5194/tc-12-2211-2018, 2018. a
Joughin, I., Smith, B. E., and Schoof, C. G.: Regularized Coulomb Friction
Laws for Ice Sheet Sliding: Application to Pine Island Glacier, Antarctica,
Geophys. Res. Lett., 46, 4764–4771, https://doi.org/10.1029/2019GL082526, 2019. a, b
Kulessa, B., Hubbard, A. L., Booth, A. D., Bougamont, M., Dow, C. F., Doyle,
S. H., Christoffersen, P., Lindbäck, K., Pettersson, R., Fitzpatrick, A. A. W., and Jones, G. A.: Seismic evidence for complex sedimentary control of Greenland Ice Sheet flow, Sci. Adv., 3, e1603071, https://doi.org/10.1126/sciadv.1603071, 2017. a, b, c
Larour, E., Utke, J., Csatho, B., Schenk, A., Seroussi, H., Morlighem, M.,
Rignot, E., Schlegel, N., and Khazendar, A.: Inferred basal friction and
surface mass balance of the Northeast Greenland Ice Stream using data
assimilation of ICESat (Ice Cloud and land Elevation Satellite) surface
altimetry and ISSM (Ice Sheet System Model), The Cryosphere, 8, 2335–2351,
https://doi.org/10.5194/tc-8-2335-2014, 2014. a
Le Clec'h, S., Charbit, S., Quiquet, A., Fettweis, X., Dumas, C., Kageyama,
M., Wyard, C., and Ritz, C.: Assessment of the Greenland ice sheet-atmosphere feedbacks for the next century with a regional atmospheric
model coupled to an ice sheet model, The Cryosphere, 13, 373–395,
https://doi.org/10.5194/tc-13-373-2019, 2019. a
Lemos, A., Shepherd, A., McMillan, M., and Hogg, A.: Seasonal Variations in
the Flow of Land-Terminating Glaciers in Central-West Greenland Using
Sentinel-1 Imagery, Remote Sens., 10, 1878, https://doi.org/10.3390/rs10121878, 2018. a, b
Lindbäck, K., Pettersson, R., Doyle, S. H., Helanow, C., Jansson, P.,
Kristensen, S. S., Stenseng, L., Forsberg, R., and Hubbard, A. L.: High-resolution ice thickness and bed topography of a land-terminating
section of the Greenland Ice Sheet, Earth Syst. Sci. Data, 6, 331–338,
https://doi.org/10.5194/essd-6-331-2014, 2014. a
MacAyeal, D. R.: A tutorial on the use of control methods in ice-sheet modeling, J. Glaciol., 39, 91–98, https://doi.org/10.1017/S0022143000015744, 1993. a
Maier, N., Humphrey, N., Meierbachtol, T., and Harper, J.: Deformation motion
tracks sliding changes through summer, western Greenland, J. Glaciol., https://doi.org/10.1017/jog.2021.87, in press, 2021b. a
Mangeney, A., Califano, F., and Castelnau, O.: Isothermal flow of an anisotropic ice sheet in the vicinity of an ice divide, J. Geophys. Res.-Solid, 101, 28189–28204, https://doi.org/10.1029/96jb01924, 1996. a
Meierbachtol, T., Harper, J., and Humphrey, N.: Basal drainage system response to increasing surface melt on the Greenland ice sheet, Science, 341,
777–779, https://doi.org/10.1126/science.1235905, 2013. a, b, c, d
Mikkelsen, A. B., Hubbard, A., Macferrin, M., Box, J. E., Doyle, S. H.,
Fitzpatrick, A., Hasholt, B., Bailey, H. L., Lindbäck, K., and Pettersson, R.: Extraordinary runoff from the Greenland ice sheet in 2012 amplified by hypsometry and depleted firn retention, The Cryosphere, 10,
1147–1159, https://doi.org/10.5194/tc-10-1147-2016, 2016. a
Millan, R., Mouginot, J., Rabatel, A., Jeong, S., Cusicanqui, D., Derkacheva,
A., and Chekki, M.: Mapping surface flow velocity of glaciers at regional
scale using a multiple sensors approach, Remote Sens., 11, 1–21,
https://doi.org/10.3390/rs11212498, 2019. a
Minchew, B., Simons, M., Björnsson, H., Pálsson, F., Morlighem, M.,
Seroussi, H., Larour, E., and Hensley, S.: Plastic bed beneath Hofsjökull ice cap, central Iceland, and the sensitivity of ice flow to surface meltwater flux, J. Glaciol., 62, 147–158, https://doi.org/10.1017/jog.2016.26, 2016. a
Morlighem, M., Rignot, E., Seroussi, H., Larour, E., Ben Dhia, H., and Aubry,
D.: A mass conservation approach for mapping glacier ice thickness, Geophys. Res. Lett., 38, 1–6, https://doi.org/10.1029/2011GL048659, 2011. a
Morlighem, M., Rignot, E., Mouginot, J., Wu, X., Seroussi, H., Larour, E., and Paden, J.: High-resolution bed topography mapping of Russell Glacier,
Greenland, inferred from Operation IceBridge data, J. Glaciol., 59, 1015–1023, https://doi.org/10.3189/2013JoG12J235, 2013. a
Morlighem, M., Williams, C. N., Rignot, E., An, L., Arndt, J. E., Bamber, J. L., Catania, G., Chauché, N., Dowdeswell, J. A., Dorschel, B., Fenty, I., Hogan, K., Howat, I., Hubbard, A., Jakobsson, M., Jordan, T. M., Kjeldsen, K. K., Millan, R., Mayer, L., Mouginot, J., Noël, B. P., O'Cofaigh, C., Palmer, S., Rysgaard, S., Seroussi, H., Siegert, M. J., Slabon, P., Straneo, F., van den Broeke, M. R., Weinrebe, W., Wood, M., and Zinglersen, K. B.: BedMachine v3: Complete Bed Topography and Ocean Bathymetry Mapping of Greenland From Multibeam Echo Sounding Combined With Mass Conservation, Geophys. Res. Lett., 44, 11051–11061, https://doi.org/10.1002/2017GL074954, 2017. a, b, c, d, e
Mouginot, J., Rignot, E., Scheuchl, B., and Millan, R.: Comprehensive Annual
Ice Sheet Velocity Mapping Using Landsat-8, Sentinel-1, and RADARSAT-2 Data,
Remote Sen., 9, 1–20, https://doi.org/10.3390/rs9040364, 2017. a, b, c
Mouginot, J., Rignot, E., Bjørk, A. A., van den Broeke, M., Millan, R.,
Morlighem, M., Noël, B., Scheuchl, B., and Wood, M.: Forty-six years
of Greenland Ice Sheet mass balance from 1972 to 2018, P. Natl. Acad. Sci. USA, 116, 9239–9244, https://doi.org/10.1073/pnas.1904242116, 2019. a
Nienow, P. W., Sole, A. J., Slater, D. A., and Cowton, T. R.: Recent Advances in Our Understanding of the Role of Meltwater in the Greenland Ice Sheet
System, Curr. Clim. Change Rep., 3, 330–344, https://doi.org/10.1007/s40641-017-0083-9, 2017. a, b, c
Palmer, S., Shepherd, A., Nienow, P., and Joughin, I.: Seasonal speedup of the Greenland Ice Sheet linked to routing of surface water, Earth Planet. Sc. Lett., 302, 423–428, https://doi.org/10.1016/j.epsl.2010.12.037, 2011. a, b, c
Pimentel, S., Flowers, G. E., and Schoof, C. G.: A hydrologically coupled
higher-order flow-band model of ice dynamics with a Coulomb friction sliding
law, J. Geophys. Res.-Earth, 115, 1–16, https://doi.org/10.1029/2009JF001621, 2010. a
Poinar, K., Joughin, I., Das, S. B., Behn, M. D., Lenaerts, J. T., and Van Den Broeke, M. R.: Limits to future expansion of surface-melt-enhanced ice flow into the interior of western Greenland, Geophys. Res. Lett., 42,
1800–1807, https://doi.org/10.1002/2015GL063192, 2015. a
Price, S. F., Payne, A. J., Catania, G. A., and Neumann, T. A.: Seasonal
acceleration of inland ice via longitudinal coupling to marginal ice, J. Glaciol., 54, 213–219, https://doi.org/10.3189/002214308784886117, 2008. a
Rignot, E. and Mouginot, J.: Ice flow in Greenland for the International Polar Year 2008–2009, Geophys. Res. Lett., 39, 1–7, https://doi.org/10.1029/2012GL051634, 2012. a
Ryser, C., Lüthi, M. P., Andrews, L. C., Catania, G. A., Funk, M., and
Hawley, R.: Caterpillar-like ice motion in the ablation zone of the Greenland ice sheet, J. Geophys. Res.-Earth, 119, 2258–2271, https://doi.org/10.1002/2013JF003067, 2014a. a
Ryser, C., Luthi, M. P., Andrews, L. C., Hoffman, M. J., Catania, G. A.,
Hawley, R. L., Neumann, T. A., and Kristensen, S. S.: Sustained high basal
motion of the Greenland ice sheet revealed by borehole deformation, J. Glaciol., 60, 647–660, https://doi.org/10.3189/2014JoG13J196, 2014b. a, b
Scambos, T. A. and Haran, T.: An image-enhanced DEM of the Greenland ice
sheet, Ann. Glaciol., 34, 291–298, https://doi.org/10.3189/172756402781817969, 2002. a
Schäfer, M., Gillet-Chaulet, F., Gladstone, R., Pettersson, R., Pohjola,
V. A., Strozzi, T., and Zwinger, T.: Assessment of heat sources on the control of fast flow of Vestfonna ice cap, Svalbard, The Cryosphere, 8,
1951–1973, https://doi.org/10.5194/tc-8-1951-2014, 2014. a
Schoof, C.: The effect of cavitation on glacier sliding, P. Roy. Soc. A, 461,
609–627, https://doi.org/10.1098/rspa.2004.1350, 2005. a, b, c, d
Shapero, D. R., Joughin, I. R., Poinar, K., Morlighem, M., and Gillet-Chaulet, F.: Basal resistance for three of the largest Greenland outlet glaciers, J. Geophys. Res.-Earth, 121, 168–180,
https://doi.org/10.1002/2015JF003643, 2016. a
Smeets, C. J. P. P., Boot, W., Hubbard, A., Pettersson, R., Wilhelms, F., Van Den Broeke, M. R., and Van De Wal, R. S. W.: A wireless subglacial probe for deep ice applications, Instrum. Meth., 58, 841–848,
https://doi.org/10.3189/2012JoG11J130, 2012. a, b, c
Smith, L. C., Chu, V. W., Yang, K., Gleason, C. J., Pitcher, L. H., Rennermalm, A. K., Legleiter, C. J., Behar, A. E., Overstreet, B. T., Moustafa, S. E., Tedesco, M., Forster, R. R., LeWinter, A. L., Finnegan, D. C., Sheng, Y., and Balog, J.: Efficient meltwater drainage through supraglacial streams and rivers on the southwest Greenland ice sheet, P. Natl. Acad. Sci. USA, 112, 1001–1006, https://doi.org/10.1073/pnas.1413024112, 2015. a
Sole, A., Nienow, P., Bartholomew, I., Mair, D., Cowton, T., Tedstone, A., and King, M. A.: Winter motion mediates dynamic response of the Greenland Ice
Sheet to warmer summers, Geophys. Res. Lett., 40, 3940–3944,
https://doi.org/10.1002/grl.50764, 2013. a, b
Stevens, L. A., Behn, M. D., Das, S. B., Joughin, I., Noël, B. P., van den Broeke, M. R., and Herring, T.: Greenland Ice Sheet flow response to
runoff variability, Geophys. Res. Lett., 43, 11295–11303,
https://doi.org/10.1002/2016GL070414, 2016. a, b
Sugiyama, S. and Gudmundsson, G. H.: Short-term variations in glacier flow
controlled by subglacial water pressure at Lauteraargletscher, Bernese Alps,
Switzerland, J. Glaciol., 50, 353–362, https://doi.org/10.3189/172756504781829846, 2004. a
Sundal, A. V., Shepherd, A., Nienow, P., Hanna, E., Palmer, S., and Huybrechts, P.: Melt-induced speed-up of Greenland ice sheet offset by efficient subglacial drainage, Nature, 469, 521–524, https://doi.org/10.1038/nature09740, 2011. a
Tedstone, A., Nienow, P. W., Gourmelen, N., Dehecq, A., Goldberg, D., and
Hanna, E.: Decadal slowdown of a land-terminating sector of the Greenland
Ice Sheet despite warming, Nature, 526, 692–695, https://doi.org/10.1038/nature15722,
2015. a, b
Tedstone, A. J., Nienow, P. W., Sole, A. J., Mair, D. W. F., Cowton, T. R.,
Bartholomew, I. D., and King, M. A.: Greenland ice sheet motion insensitive
to exceptional meltwater forcing, P. Natl. Acad. Sci. USA, 110, 19719–19724, https://doi.org/10.1073/pnas.1315843110, 2013. a
Tedstone, A. J., Nienow, P. W., Gourmelen, N., and Sole, A. J.: Greenland ice
sheet annual motion insensitive to spatial variations in subglacial hydraulic
structure, Geophys. Res. Lett., 41, 8910–8917, https://doi.org/10.1002/2014GL062386, 2014. a
Truffer, M., Harrison, W. D., and Echelmeyer, K. A.: Glacier motion dominated
by processes deep in underlying till, J. Glaciol., 46, 213–221,
https://doi.org/10.3189/172756500781832909, 2000. a
Trusel, L. D., Das, S. B., Osman, M. B., Evans, M. J., Smith, B. E., Fettweis, X., McConnell, J. R., Noël, B. P., and van den Broeke, M. R.:
Nonlinear rise in Greenland runoff in response to post-industrial Arctic
warming, Nature, 564, 104–108, https://doi.org/10.1038/s41586-018-0752-4, 2018. a
Van De Wal, R. S., Boot, W., Smeets, C. J., Snellen, H., Van Den Broeke, M. R., and Oerlemans, J.: Twenty-one years of mass balance observations along the K-transect, West Greenland, Earth Syst. Sci. Data, 4, 31–35,
https://doi.org/10.5194/essd-4-31-2012, 2012. a
Van De Wal, R. S., Smeets, C. J., Boot, W., Stoffelen, M., Van Kampen, R.,
Doyle, S. H., Wilhelms, F., Van Den Broeke, M. R., Reijmer, C. H., Oerlemans, J., and Hubbard, A.: Self-regulation of ice flow varies across the ablation area in south-west Greenland, The Cryosphere, 9, 603–611,
https://doi.org/10.5194/tc-9-603-2015, 2015. a, b, c, d, e, f
Van Tricht, K., Lhermitte, S., Lenaerts, J. T., Gorodetskaya, I. V., L'Ecuyer, T. S., Noël, B., Van Den Broeke, M. R., Turner, D. D., and
Van Lipzig, N. P.: Clouds enhance Greenland ice sheet meltwater runoff, Nat. Commun., 7, 10266, https://doi.org/10.1038/ncomms10266, 2016. a
Vijay, S., Khan, S. A., Kusk, A., Solgaard, A. M., Moon, T., and Bjørk,
A. A.: Resolving Seasonal Ice Velocity of 45 Greenlandic Glaciers With Very
High Temporal Details, Geophys. Res. Lett., 46, 1485–1495,
https://doi.org/10.1029/2018GL081503, 2019. a
Weertman, J.: On the sliding of glaciers, J. Glaciol., 3, 33–38, https://doi.org/10.1007/978-94-015-8705-1_19, 1957. a
Yang, Y., Li, F., Hwang, C., Ding, M., and Ran, J.: Space-Time Evolution of
Greenland Ice Sheet Elevation and Mass From Envisat and GRACE Data, J. Geophys. Res.-Earth, 124, 2079–2100, https://doi.org/10.1029/2018JF004765, 2019. a
Young, T. J., Christoffersen, P., Doyle, S. H., Nicholls, K. W., Stewart, C. L., Hubbard, B., Hubbard, A., Lok, L. B., Brennan, P. V., Benn, D. I., Luckman, A., and Bougamont, M.: Physical Conditions of Fast Glacier Flow:
3. Seasonally-Evolving Ice Deformation on Store Glacier, West Greenland, J. Geophys. Res.-Earth, 124, 245–267, https://doi.org/10.1029/2018JF004821, 2019.
a
Zoet, L. K. and Iverson, N. R.: A slip law for glaciers on deformable beds,
Science, 368, 76–78, https://doi.org/10.1126/science.aaz1183, 2020. a
Zwally, H. J., Abdalati, W., Herring, T., Larson, K., Saba, J., and Steffen,
K.: Surface melt-induced acceleration of Greenland ice-sheet flow, Science,
297, 218–222, https://doi.org/10.1126/science.1072708, 2002. a
Short summary
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.
Along the edges of the Greenland Ice Sheet surface melt lubricates the bed and causes large...