Articles | Volume 19, issue 11
https://doi.org/10.5194/tc-19-5531-2025
© Author(s) 2025. 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-19-5531-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Nov 2025
Research article |
| 11 Nov 2025
| 11 Nov 2025
Using observations of surface fracture to address ill-posed ice softness estimation over Pine Island Glacier
Trystan Surawy-Stepney
CORRESPONDING AUTHOR
School of Earth and Environment, University of Leeds, Leeds, United Kingdom
Stephen L. Cornford
Department of Geographical Sciences, University of Bristol, Bristol, United Kingdom
Anna E. Hogg
School of Earth and Environment, University of Leeds, Leeds, United Kingdom
Related authors
Thomas F. Whale, Sarah L. Barr, and Trystan Surawy-Stepney
EGUsphere, https://doi.org/10.5194/egusphere-2026-680, https://doi.org/10.5194/egusphere-2026-680, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
Short summary
Short summary
Droplet-freezing experiments are used to study ice formation in the atmosphere, but standard methods to show uncertainty or test whether two results differ are lacking. We borrow from medical ‘time-to-event’ statistics to add easily-calculated confidence intervals to fraction-frozen curves and derived quantities without binning or assumptions about underlying physics, and adapt a test to judge whether curves differ beyond random variation. This will make comparison of studies easier.
Thomas F. Whale, Sarah L. Barr, and Trystan Surawy-Stepney
EGUsphere, https://doi.org/10.5194/egusphere-2026-680, https://doi.org/10.5194/egusphere-2026-680, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
Short summary
Short summary
Droplet-freezing experiments are used to study ice formation in the atmosphere, but standard methods to show uncertainty or test whether two results differ are lacking. We borrow from medical ‘time-to-event’ statistics to add easily-calculated confidence intervals to fraction-frozen curves and derived quantities without binning or assumptions about underlying physics, and adapt a test to judge whether curves differ beyond random variation. This will make comparison of studies easier.
Luisa E. Avilés-Podgurski, Patrick Martineau, Hua Lu, Ayako Yamamoto, Amanda C. Maycock, Andrew Orr, Tony Phillips, Thomas J. Bracegirdle, Anna E. Hogg, Grzegorz Muszynski, and Andrew Fleming
EGUsphere, https://doi.org/10.5194/egusphere-2025-6285, https://doi.org/10.5194/egusphere-2025-6285, 2026
Short summary
Short summary
Atmospheric rivers (ARs) are narrow filaments transporting vast amounts of water vapour poleward. Rarely, they reach the Arctic, driving strong warming and melt. In April 2020, two ARs reached the central Arctic within one week, raising near-surface temperatures by up to 30 °C and leading to extreme precipitation. Their distinct paths and thermodynamic evolution reveal diverse AR impacts on Arctic sea ice and precipitation extremes.
Sarah Leibrock, Ross A. W. Slater, Anna E. Hogg, and Celia A. Baumhoer
EGUsphere, https://doi.org/10.5194/egusphere-2025-5492, https://doi.org/10.5194/egusphere-2025-5492, 2025
Short summary
Short summary
Using satellite data from 2013 to 2024, we studied 42 Antarctic Peninsula glaciers and observed widespread but spatially heterogeneous retreat and ice flow acceleration, with some glaciers more than doubling in speed. In addition to these long-term trends, glacier dynamics exhibited significant seasonal variability, underscoring the highly dynamic nature of glaciers in this region driven by a combination of glacier-specific and environmental factors.
Harry J. Davis, Robert G. Bingham, Carlos Martín, Elizabeth R. Thomas, Andrew S. Hein, and Anna E. Hogg
EGUsphere, https://doi.org/10.5194/egusphere-2025-5467, https://doi.org/10.5194/egusphere-2025-5467, 2025
Short summary
Short summary
Ice in the southern Antarctic Peninsula is experiencing major ice changes today and predicting the rate at which this may continue is important. One way to address this knowledge gap would be to retrieve a past climate record from an ice core. We identify a suitable site using a model constrained by radar and shallow ice core data. We find a climate record spanning the Holocene can certainly be extracted here, but a potential continuous climate record here could extend back ~30,000 years.
Katie Lowery, Pierre Dutrieux, Paul R. Holland, Anna E. Hogg, Noel Gourmelen, and Benjamin J. Wallis
The Cryosphere, 19, 4893–4911, https://doi.org/10.5194/tc-19-4893-2025, https://doi.org/10.5194/tc-19-4893-2025, 2025
Short summary
Short summary
Using CryoSat-2, we observe monthly changes in the Pine Island Glacier (PIG) ice shelf surface and derive oceanic melt at its base. Basal channels, kilometres wide, are reflected in the ice surface and captured in our observations. We demonstrate that melt is concentrated on the western walls of channels, that channels play a role in grounding pinning points, and that PIG's main channel geometry is inherited upstream of the grounding line. These results highlight the importance of channels to ice shelf stability.
Yikai Zhu, Anna E. Hogg, Andrew Hooper, and Benjamin J. Wallis
The Cryosphere, 19, 3971–3989, https://doi.org/10.5194/tc-19-3971-2025, https://doi.org/10.5194/tc-19-3971-2025, 2025
Short summary
Short summary
This study investigates the long- and short-term changes in the grounding line of the Amery Ice Shelf in East Antarctica, using satellite observations and a method called Differential Range Offset Tracking (DROT). Our findings show how the grounding line behaves in response to tides and other environmental factors, with implications for understanding ice shelf stability.
Jennifer Cocks, Alessandro Silvano, Alberto C. Naveira Garabato, Oana Dragomir, Noémie Schifano, Anna E. Hogg, and Alice Marzocchi
Ocean Sci., 21, 1609–1625, https://doi.org/10.5194/os-21-1609-2025, https://doi.org/10.5194/os-21-1609-2025, 2025
Short summary
Short summary
Heat and freshwater fluxes in the Southern Ocean mediate global ocean circulation and abyssal ventilation. These fluxes manifest as changes in steric height: sea level anomalies from changes in ocean density. We compute the steric height anomaly of the Southern Ocean using satellite data and validate it against in situ observations. We analyse trends and variability in steric height, drawing links to climate variability, and discuss the effectiveness of the method, highlighting issues with its application.
Benjamin J. Davison, Anna E. Hogg, Thomas Slater, Richard Rigby, and Nicolaj Hansen
Earth Syst. Sci. Data, 17, 3259–3281, https://doi.org/10.5194/essd-17-3259-2025, https://doi.org/10.5194/essd-17-3259-2025, 2025
Short summary
Short summary
Grounding line discharge is a measure of the amount of ice entering the ocean from an ice mass. This paper describes a dataset of grounding line discharge for the Antarctic Ice Sheet and each of its glaciers. The dataset shows that Antarctic Ice Sheet grounding line discharge has increased since 1996.
Heather L. Selley, Anna E. Hogg, Benjamin J. Davison, Pierre Dutrieux, and Thomas Slater
The Cryosphere, 19, 1725–1738, https://doi.org/10.5194/tc-19-1725-2025, https://doi.org/10.5194/tc-19-1725-2025, 2025
Short summary
Short summary
We used satellite observations to measure recent changes in ice speed and flow direction in the Pope, Smith, and Kohler region of West Antarctica (2005–2022). We found substantial speed-up on seven ice streams of up to 87 %. However, Kohler West Glacier has slowed by 10 %, due to the redirection of ice flow into its rapidly thinning neighbour. This process of “ice piracy” has not previously been directly observed on this rapid timescale and may influence future ice shelf and sheet mass changes.
Violet L. Patterson, Lauren J. Gregoire, Ruza F. Ivanovic, Niall Gandy, Stephen Cornford, Jonathan Owen, Sam Sherriff-Tadano, and Robin S. Smith
EGUsphere, https://doi.org/10.5194/egusphere-2024-3896, https://doi.org/10.5194/egusphere-2024-3896, 2025
Short summary
Short summary
Simulations of the last two glacial periods are ran using a computer model in which the atmosphere and ice sheets interact. The model is able to produce ice sheet volumes, extents and dynamics in good agreement with data. Sensitivity analysis is undertaken and shows the Northern Hemisphere ice sheet size is particularly sensitive to the albedo of the ice in the model but the different ice sheets display different sensitivities to other processes.
James F. O'Neill, Tamsin L. Edwards, Daniel F. Martin, Courtney Shafer, Stephen L. Cornford, Hélène L. Seroussi, Sophie Nowicki, Mira Adhikari, and Lauren J. Gregoire
The Cryosphere, 19, 541–563, https://doi.org/10.5194/tc-19-541-2025, https://doi.org/10.5194/tc-19-541-2025, 2025
Short summary
Short summary
We use an ice sheet model to simulate the Antarctic contribution to sea level over the 21st century under a range of future climates and varying how sensitive the ice sheet is to different processes. We find that ocean temperatures increase and more snow falls on the ice sheet under stronger warming scenarios. When the ice sheet is sensitive to ocean warming, ocean melt-driven loss exceeds snowfall-driven gains, meaning that the sea level contribution is greater with more climate warming.
Matt Trevers, Antony J. Payne, and Stephen L. Cornford
The Cryosphere, 18, 5101–5115, https://doi.org/10.5194/tc-18-5101-2024, https://doi.org/10.5194/tc-18-5101-2024, 2024
Short summary
Short summary
The form of the friction law which determines the speed of ice sliding over the bedrock remains a major source of uncertainty in ice sheet model projections of future sea level rise. Jakobshavn Isbræ, the fastest-flowing glacier in Greenland, which has undergone significant changes in the last few decades, is an ideal case for testing sliding laws. We find that a regularised Coulomb friction law reproduces the large seasonal and inter-annual flow speed variations most accurately.
Benjamin J. Wallis, Anna E. Hogg, Yikai Zhu, and Andrew Hooper
The Cryosphere, 18, 4723–4742, https://doi.org/10.5194/tc-18-4723-2024, https://doi.org/10.5194/tc-18-4723-2024, 2024
Short summary
Short summary
The grounding line, where ice begins to float, is an essential variable to understand ice dynamics, but in some locations it can be challenging to measure with established techniques. Using satellite data and a new method, Wallis et al. measure the grounding line position of glaciers and ice shelves in the Antarctic Peninsula and find retreats of up to 16.3 km have occurred since the last time measurements were made in the 1990s.
Benjamin J. Davison, Anna E. Hogg, Carlos Moffat, Michael P. Meredith, and Benjamin J. Wallis
The Cryosphere, 18, 3237–3251, https://doi.org/10.5194/tc-18-3237-2024, https://doi.org/10.5194/tc-18-3237-2024, 2024
Short summary
Short summary
Using a new dataset of ice motion, we observed glacier acceleration on the west coast of the Antarctic Peninsula. The speed-up began around January 2021, but some glaciers sped up earlier or later. Using a combination of ship-based ocean temperature observations and climate models, we show that the speed-up coincided with a period of unusually warm air and ocean temperatures in the region.
Trystan Surawy-Stepney, Anna E. Hogg, Stephen L. Cornford, Benjamin J. Wallis, Benjamin J. Davison, Heather L. Selley, Ross A. W. Slater, Elise K. Lie, Livia Jakob, Andrew Ridout, Noel Gourmelen, Bryony I. D. Freer, Sally F. Wilson, and Andrew Shepherd
The Cryosphere, 18, 977–993, https://doi.org/10.5194/tc-18-977-2024, https://doi.org/10.5194/tc-18-977-2024, 2024
Short summary
Short summary
Here, we use satellite observations and an ice flow model to quantify the impact of sea ice buttressing on ice streams on the Antarctic Peninsula. The evacuation of 11-year-old landfast sea ice in the Larsen B embayment on the East Antarctic Peninsula in January 2022 was closely followed by major changes in the calving behaviour and acceleration (30 %) of the ocean-terminating glaciers. Our results show that sea ice buttressing had a negligible direct role in the observed dynamic changes.
Trystan Surawy-Stepney, Anna E. Hogg, Stephen L. Cornford, and David C. Hogg
The Cryosphere, 17, 4421–4445, https://doi.org/10.5194/tc-17-4421-2023, https://doi.org/10.5194/tc-17-4421-2023, 2023
Short summary
Short summary
The presence of crevasses in Antarctica influences how the ice sheet behaves. It is important, therefore, to collect data on the spatial distribution of crevasses and how they are changing. We present a method of mapping crevasses from satellite radar imagery and apply it to 7.5 years of images, covering Antarctica's floating and grounded ice. We develop a method of measuring change in the density of crevasses and quantify increased fracturing in important parts of the West Antarctic Ice Sheet.
Bryony I. D. Freer, Oliver J. Marsh, Anna E. Hogg, Helen Amanda Fricker, and Laurie Padman
The Cryosphere, 17, 4079–4101, https://doi.org/10.5194/tc-17-4079-2023, https://doi.org/10.5194/tc-17-4079-2023, 2023
Short summary
Short summary
We develop a method using ICESat-2 data to measure how Antarctic grounding lines (GLs) migrate across the tide cycle. At an ice plain on the Ronne Ice Shelf we observe 15 km of tidal GL migration, the largest reported distance in Antarctica, dominating any signal of long-term migration. We identify four distinct migration modes, which provide both observational support for models of tidal ice flexure and GL migration and insights into ice shelf–ocean–subglacial interactions in grounding zones.
Julia R. Andreasen, Anna E. Hogg, and Heather L. Selley
The Cryosphere, 17, 2059–2072, https://doi.org/10.5194/tc-17-2059-2023, https://doi.org/10.5194/tc-17-2059-2023, 2023
Short summary
Short summary
There are few long-term, high spatial resolution observations of ice shelf change in Antarctica over the past 3 decades. In this study, we use high spatial resolution observations to map the annual calving front location on 34 ice shelves around Antarctica from 2009 to 2019 using satellite data. The results provide a comprehensive assessment of ice front migration across Antarctica over the last decade.
Sarah S. Thompson, Bernd Kulessa, Adrian Luckman, Jacqueline A. Halpin, Jamin S. Greenbaum, Tyler Pelle, Feras Habbal, Jingxue Guo, Lenneke M. Jong, Jason L. Roberts, Bo Sun, and Donald D. Blankenship
The Cryosphere, 17, 157–174, https://doi.org/10.5194/tc-17-157-2023, https://doi.org/10.5194/tc-17-157-2023, 2023
Short summary
Short summary
We use satellite imagery and ice penetrating radar to investigate the stability of the Shackleton system in East Antarctica. We find significant changes in surface structures across the system and observe a significant increase in ice flow speed (up to 50 %) on the floating part of Scott Glacier. We conclude that knowledge remains woefully insufficient to explain recent observed changes in the grounded and floating regions of the system.
Douglas I. Benn, Adrian Luckman, Jan A. Åström, Anna J. Crawford, Stephen L. Cornford, Suzanne L. Bevan, Thomas Zwinger, Rupert Gladstone, Karen Alley, Erin Pettit, and Jeremy Bassis
The Cryosphere, 16, 2545–2564, https://doi.org/10.5194/tc-16-2545-2022, https://doi.org/10.5194/tc-16-2545-2022, 2022
Short summary
Short summary
Thwaites Glacier (TG), in West Antarctica, is potentially unstable and may contribute significantly to sea-level rise as global warming continues. Using satellite data, we show that Thwaites Eastern Ice Shelf, the largest remaining floating extension of TG, has started to accelerate as it fragments along a shear zone. Computer modelling does not indicate that fragmentation will lead to imminent glacier collapse, but it is clear that major, rapid, and unpredictable changes are underway.
Martin Horwath, Benjamin D. Gutknecht, Anny Cazenave, Hindumathi Kulaiappan Palanisamy, Florence Marti, Ben Marzeion, Frank Paul, Raymond Le Bris, Anna E. Hogg, Inès Otosaka, Andrew Shepherd, Petra Döll, Denise Cáceres, Hannes Müller Schmied, Johnny A. Johannessen, Jan Even Øie Nilsen, Roshin P. Raj, René Forsberg, Louise Sandberg Sørensen, Valentina R. Barletta, Sebastian B. Simonsen, Per Knudsen, Ole Baltazar Andersen, Heidi Ranndal, Stine K. Rose, Christopher J. Merchant, Claire R. Macintosh, Karina von Schuckmann, Kristin Novotny, Andreas Groh, Marco Restano, and Jérôme Benveniste
Earth Syst. Sci. Data, 14, 411–447, https://doi.org/10.5194/essd-14-411-2022, https://doi.org/10.5194/essd-14-411-2022, 2022
Short summary
Short summary
Global mean sea-level change observed from 1993 to 2016 (mean rate of 3.05 mm yr−1) matches the combined effect of changes in water density (thermal expansion) and ocean mass. Ocean-mass change has been assessed through the contributions from glaciers, ice sheets, and land water storage or directly from satellite data since 2003. Our budget assessments of linear trends and monthly anomalies utilise new datasets and uncertainty characterisations developed within ESA's Climate Change Initiative.
Cited articles
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, Journal of Geophysical Research: Earth Surface, 120, 1171–1188, https://doi.org/10.1002/2014JF003239, 2015. a
Benn, D. I. and Evans, D. J.: Glaciers & glaciation, Routledge, ISBN 9780340905791, 2014. a
Bevan, S., Cornford, S., Gilbert, L., Otosaka, I., Martin, D., and Surawy-Stepney, T.: Amundsen Sea Embayment ice-sheet mass-loss predictions to 2050 calibrated using observations of velocity and elevation change, Journal of Glaciology, 1–11, https://doi.org/10.1017/jog.2023.57, 2023. a
Borstad, C., Khazendar, A., Scheuchl, B., Morlighem, M., Larour, E., and Rignot, E.: A constitutive framework for predicting weakening and reduced buttressing of ice shelves based on observations of the progressive deterioration of the remnant Larsen B Ice Shelf, Geophysical Research Letters, 43, 2027–2035, https://doi.org/10.1002/2015GL067365, 2016. a
Borstad, C. P., Rignot, E., Mouginot, J., and Schodlok, M. P.: Creep deformation and buttressing capacity of damaged ice shelves: theory and application to Larsen C ice shelf, The Cryosphere, 7, 1931–1947, https://doi.org/10.5194/tc-7-1931-2013, 2013. a
Brinkerhoff, D. J. and Johnson, J. V.: Data assimilation and prognostic whole ice sheet modelling with the variationally derived, higher order, open source, and fully parallel ice sheet model VarGlaS, The Cryosphere, 7, 1161–1184, https://doi.org/10.5194/tc-7-1161-2013, 2013. a
Chamorro-Servent, J., Dubois, R., and Coudière, Y.: Considering New Regularization Parameter-Choice Techniques for the Tikhonov Method to Improve the Accuracy of Electrocardiographic Imaging, Frontiers in Physiology, 10, https://doi.org/10.3389/fphys.2019.00273, 2019. a
Chartrand, R.: Numerical differentiation of noisy, nonsmooth, multidimensional data, in: 2017 IEEE Global Conference on Signal and Information Processing (GlobalSIP), 244–248, https://doi.org/10.1109/GlobalSIP.2017.8308641, 2017. a
Cornford, S. L., Martin, D. F., Graves, D. T., Ranken, D. F., Le Brocq, A. M., Gladstone, R. M., Payne, A. J., Ng, E. G., and Lipscomb, W. H.: Adaptive mesh, finite volume modeling of marine ice sheets, Journal of Computational Physics, 232, 529–549, https://doi.org/10.1016/j.jcp.2012.08.037, 2013. a
Cornford, S. L., Martin, D. F., Payne, A. J., Ng, E. G., Le Brocq, A. M., Gladstone, R. M., Edwards, T. L., Shannon, S. R., Agosta, C., van den Broeke, M. R., Hellmer, H. H., Krinner, G., Ligtenberg, S. R. M., Timmermann, R., and Vaughan, D. G.: Century-scale simulations of the response of the West Antarctic Ice Sheet to a warming climate, The Cryosphere, 9, 1579–1600, https://doi.org/10.5194/tc-9-1579-2015, 2015. a, b, c
Cuffey, K. M. and Paterson, W. S. B.: The physics of glaciers, Academic Press, ISBN 978-0-123-69461-4, 2010. a
Gerli, C., Rosier, S., Gudmundsson, G. H., and Sun, S.: Weak relationship between remotely detected crevasses and inferred ice rheological parameters on Antarctic ice shelves , The Cryosphere, 18, 2677–2689, https://doi.org/10.5194/tc-18-2677-2024, 2024. a
Goldberg, D. N., Heimbach, P., Joughin, I., and Smith, B.: Committed retreat of Smith, Pope, and Kohler Glaciers over the next 30 years inferred by transient model calibration, The Cryosphere, 9, 2429–2446, https://doi.org/10.5194/tc-9-2429-2015, 2015. a
Goldberg, D. N., Gourmelen, N., Kimura, S., Millan, R., and Snow, K.: How Accurately Should We Model Ice Shelf Melt Rates?, Geophysical Research Letters, 46, 189–199, https://doi.org/10.1029/2018GL080383, 2019. a
Gudmundsson, G. H., Paolo, F. S., Adusumilli, S., and Fricker, H. A.: Instantaneous Antarctic ice sheet mass loss driven by thinning ice shelves, Geophysical Research Letters, 46, 13903–13909, https://doi.org/10.1029/2019GL085027, 2019. a
Habermann, M., Truffer, M., and Maxwell, D.: Changing basal conditions during the speed-up of Jakobshavn Isbræ, Greenland, The Cryosphere, 7, 1679–1692, https://doi.org/10.5194/tc-7-1679-2013, 2013. a
Haefeli, R.: Contribution to the Movement and the form of Ice Sheets in the Arctic and Antarctic, Journal of Glaciology, 3, 1133–1151, https://doi.org/10.3189/S0022143000017548, 1961. a
Hansen, P.: The L-curve and its use in the numerical treatment of inverse problems, in: InviteComputational Inverse Problems in Electrocardiology, WIT Press, inviteComputational Inverse Problems in Electrocardiology, Conference date, 1 January 2000, 2000. a
Hansen, P. C.: Regularization tools: A Matlab package for analysis and solution of discrete ill-posed problems, Numerical Algorithms, 6, 1–35, https://doi.org/10.1007/BF02149761, 1994. a
Hansen, P. C. and O'Leary, D. P.: The Use of the L-Curve in the Regularization of Discrete Ill-Posed Problems, SIAM Journal on Scientific Computing, 14, 1487–1503, https://doi.org/10.1137/0914086, 1993. a, b, c
Haran, T. M., Bohlander, J., Scambos, T. A., Painter, T. H., and Fahnestock, M. A.: MODIS Mosaic of Antarctica 2003–2004 (MOA2004) Image Map, Version 2, National Snow and Ice Data Center Distributed Active Archive Center [data set], https://doi.org/10.5067/68TBT0CGJSOJ, 2021. a, b, c
Hogg, A. E., Shepherd, A., Cornford, S. L., Briggs, K. H., Gourmelen, N., Graham, J. A., Joughin, I., Mouginot, J., Nagler, T., Payne, A. J., Rignot, E., and Wuite, J.: Increased ice flow in Western Palmer Land linked to ocean melting, Geophysical Research Letters, 44, 4159–4167, https://doi.org/10.1002/2016GL072110, 2017. a
Izeboud, M. and Lhermitte, S.: Damage detection on antarctic ice shelves using the normalised radon transform, Remote Sensing of Environment, 284, 113359, https://doi.org/10.1016/j.rse.2022.113359, 2023. a
Joughin, I., Tulaczyk, S., Bamber, J. L., Blankenship, D., Holt, J. W., Scambos, T., and Vaughan, D. G.: Basal conditions for Pine Island and Thwaites Glaciers, West Antarctica, determined using satellite and airborne data, Journal of Glaciology, 55, 245–257, https://doi.org/10.3189/002214309788608705, 2009. a, b
Joughin, I., Shapero, D., Smith, B., Dutrieux, P., and Barham, M.: Ice-shelf retreat drives recent Pine Island Glacier speedup, Science Advances, 7, eabg3080, https://doi.org/10.1126/sciadv.abg3080, 2021. a, b, c, d
Lai, C.-Y., Kingslake, J., Wearing, M. G., Chen, P.-H. C., Gentine, P., Li, H., Spergel, J. J., and van Wessem, J. M.: Vulnerability of Antarctica’s ice shelves to meltwater-driven fracture, Nature, 584, 574–578, https://doi.org/10.1038/s41586-020-2627-8, 2020. a
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
MacAyeal, D. R.: The basal stress distribution of Ice Stream E, Antarctica, inferred by control methods, Journal of Geophysical Research: Solid Earth, 97, 595–603, 1992. a
Milovic, C., Prieto, C., Bilgic, B., Uribe, S., Acosta-Cabronero, J., Irarrazaval, P., and Tejos, C.: Comparison of parameter optimization methods for quantitative susceptibility mapping, Magnetic resonance in medicine, 85, 480–494, https://doi.org/10.1002/mrm.28435, 2021. a
Morlighem, M.: MEaSUREs BedMachine Antarctica, Version 3, NASA National Snow and Ice Data Center Distributed Active Archive Center [data set], https://doi.org/10.5067/FPSU0V1MWUB6, 2022. a
Morlighem, M., Seroussi, H., Larour, E., and Rignot, E.: Inversion of basal friction in Antarctica using exact and incomplete adjoints of a higher-order model, Journal of Geophysical Research: Earth Surface, 118, 1746–1753, https://doi.org/10.1002/jgrf.20125, 2013. a
Petra, N., Zhu, H., Stadler, G., Hughes, T. J., and Ghattas, O.: An inexact Gauss-Newton method for inversion of basal sliding and rheology parameters in a nonlinear Stokes ice sheet model, Journal of Glaciology, 58, 889–903, https://doi.org/10.3189/2012JoG11J182, 2012. a
Ranganathan, M., Minchew, B., Meyer, C. R., and Gudmundsson, G. H.: A new approach to inferring basal drag and ice rheology in ice streams, with applications to West Antarctic Ice Streams, Journal of Glaciology, 67, 229–242, https://doi.org/10.1017/jog.2020.95, 2021. a, b
Recinos, B., Goldberg, D., Maddison, J. R., and Todd, J.: A framework for time-dependent ice sheet uncertainty quantification, applied to three West Antarctic ice streams, The Cryosphere, 17, 4241–4266, https://doi.org/10.5194/tc-17-4241-2023, 2023. a
Rignot, E., Mouginot, J., and Scheuchl, B.: MEaSUREs Antarctic Grounding Line from Differential Satellite Radar Interferometry, Version 2, boulder, Colorado USA, NASA National Snow and Ice Data Center Distributed Active Archive Center [data set], https://doi.org/10.5067/IKBWW4RYHF1Q, 2016. a, b, c
Selley, H. L., Hogg, A. E., Cornford, S., Dutrieux, P., Shepherd, A., Wuite, J., Floricioiu, D., Kusk, A., Nagler, T., Gilbert, L., Slater, T., and Kim, T.-W.: Widespread increase in dynamic imbalance in the Getz region of Antarctica from 1994 to 2018, Nature Communications, 12, 1133, https://doi.org/10.1038/s41467-021-21321-1, 2021. a, b
Seroussi, H., Nowicki, S., Payne, A. J., Goelzer, H., Lipscomb, W. H., Abe-Ouchi, A., Agosta, C., Albrecht, T., Asay-Davis, X., Barthel, A., Calov, R., Cullather, R., Dumas, C., Galton-Fenzi, B. K., Gladstone, R., Golledge, N. R., Gregory, J. M., Greve, R., Hattermann, T., Hoffman, M. J., Humbert, A., Huybrechts, P., Jourdain, N. C., Kleiner, T., Larour, E., Leguy, G. R., Lowry, D. P., Little, C. M., Morlighem, M., Pattyn, F., Pelle, T., Price, S. F., Quiquet, A., Reese, R., Schlegel, N.-J., Shepherd, A., Simon, E., Smith, R. S., Straneo, F., Sun, S., Trusel, L. D., Van Breedam, J., van de Wal, R. S. W., Winkelmann, R., Zhao, C., Zhang, T., and Zwinger, T.: ISMIP6 Antarctica: a multi-model ensemble of the Antarctic ice sheet evolution over the 21st century, The Cryosphere, 14, 3033–3070, https://doi.org/10.5194/tc-14-3033-2020, 2020. a
Sun, S. and Gudmundsson, G. H.: The speedup of Pine Island Ice Shelf between 2017 and 2020: revaluating the importance of ice damage, Journal of Glaciology, 1–9, https://doi.org/10.1017/jog.2023.76, 2023. a
Sun, S., Cornford, S. L., Moore, J. C., Gladstone, R., and Zhao, L.: Ice shelf fracture parameterization in an ice sheet model, The Cryosphere, 11, 2543–2554, https://doi.org/10.5194/tc-11-2543-2017, 2017. a
Surawy-Stepney, T. and Cornford, S. L.: Additional code and data for running the simulations presented in the article “Using observations of surface fracture to address ill- posed ice softness estimation over Pine Island Glacier”, Zenodo [data set and code], https://doi.org/10.5281/zenodo.13694744, 2024. a, b
Surawy-Stepney, T., Hogg, A. E., Cornford, S. L., and Davison, B. J.: Episodic dynamic change linked to damage on the thwaites glacier ice tongue, Nature Geoscience, https://doi.org/10.1038/s41561-022-01097-9, 2023a. a
Surawy-Stepney, T., Hogg, A. E., Cornford, S. L., and Hogg, D. C.: Mapping Antarctic crevasses and their evolution with deep learning applied to satellite radar imagery, The Cryosphere, 17, 4421–4445, https://doi.org/10.5194/tc-17-4421-2023, 2023b. a, b, c, d
Vaughan, D. G.: Relating the occurrence of crevasses to surface strain rates, Journal of Glaciology, 39, 255–266, https://doi.org/10.3189/S0022143000015926, 1993. a
Wolovick, M., Humbert, A., Kleiner, T., and Rückamp, M.: Regularization and L-curves in ice sheet inverse models: a case study in the Filchner–Ronne catchment, The Cryosphere, 17, 5027–5060, https://doi.org/10.5194/tc-17-5027-2023, 2023. a
Wuite, J., Hetzenecker, M., Nagler, T., and Scheiblauer, S.: ESA Antarctic Ice Sheet Climate Change Initiative (Antarctic_Ice_Sheet_cci): Antarctic Ice Sheet Monthly Velocity from 2017 to 2020, Derived from Sentinel-1, v1, NERC EDS Centre for Environmental Data Analysis [data set], https://doi.org/10.5285/00fe090efc58446e8980992a617f632f, 2021. a
Zhao, J., Liang, S., Li, X., Duan, Y., and Liang, L.: Detection of Surface Crevasses over Antarctic Ice Shelves Using SAR Imagery and Deep Learning Method, Remote Sensing, 14, https://doi.org/10.3390/rs14030487, 2022. a
Zwally, H. J., Giovinetto, M. B., Beckley, M. A., and Saba, J. L.: Antarctic and Greenland drainage systems, GSFC Cryospheric Sciences Laboratory, 265, 2012. a
Short summary
The speed at which Antarctic ice flows is dependent on its viscosity and the slipperiness of the ice/bedrock interface. Often, these unknown variables are inferred from observations of ice speed. This article presents an attempt to make this difficult procedure easier by making use of additional information in the form of observations of crevasses, which make ice appear less viscous to numerical models. We find in some circumstances that this leads to more appealing solutions to this problem.
The speed at which Antarctic ice flows is dependent on its viscosity and the slipperiness of the...
