Articles | Volume 19, issue 6
https://doi.org/10.5194/tc-19-2321-2025
© 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-19-2321-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Jul 2025
Research article |
| 01 Jul 2025
| 01 Jul 2025
The demise of the world's largest piedmont glacier: a probabilistic forecast
Douglas J. Brinkerhoff
CORRESPONDING AUTHOR
Department of Computer Science, University of Montana, Missoula, MT, USA
Brandon S. Tober
Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
Department of Geosciences, University of Arizona, Tucson, AZ, USA
Michael Daniel
Department of Geosciences, University of Arizona, Tucson, AZ, USA
Victor Devaux-Chupin
Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA
Michael S. Christoffersen
Department of Geosciences, University of Arizona, Tucson, AZ, USA
Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA
John W. Holt
Department of Geosciences, University of Arizona, Tucson, AZ, USA
Christopher F. Larsen
Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA
Mark Fahnestock
Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA
Michael G. Loso
Wrangell–St. Elias National Park and Preserve, National Park Service, Copper Center, AK, USA
Kristin M. F. Timm
International Arctic Research Center, University of Alaska Fairbanks, Fairbanks, AK, USA
Russell C. Mitchell
Department of Computer Science, University of Montana, Missoula, MT, USA
Martin Truffer
Geophysical Institute, University of Alaska Fairbanks, Fairbanks, AK, USA
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Thiago Dias dos Santos, Mathieu Morlighem, and Douglas Brinkerhoff
The Cryosphere, 16, 179–195, https://doi.org/10.5194/tc-16-179-2022, https://doi.org/10.5194/tc-16-179-2022, 2022
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Projecting the future evolution of Greenland and Antarctica and their potential contribution to sea level rise often relies on computer simulations carried out by numerical ice sheet models. Here we present a new vertically integrated ice sheet model and assess its performance using different benchmarks. The new model shows results comparable to a three-dimensional model at relatively lower computational cost, suggesting that it is an excellent alternative for long-term simulations.
Andy Aschwanden, Timothy C. Bartholomaus, Douglas J. Brinkerhoff, and Martin Truffer
The Cryosphere, 15, 5705–5715, https://doi.org/10.5194/tc-15-5705-2021, https://doi.org/10.5194/tc-15-5705-2021, 2021
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Estimating how much ice loss from Greenland and Antarctica will contribute to sea level rise is of critical societal importance. However, our analysis shows that recent efforts are not trustworthy because the models fail at reproducing contemporary ice melt. Here we present a roadmap towards making more credible estimates of ice sheet melt.
D. Brinkerhoff and J. Johnson
Geosci. Model Dev., 8, 1275–1283, https://doi.org/10.5194/gmd-8-1275-2015, https://doi.org/10.5194/gmd-8-1275-2015, 2015
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We present a novel numerical method for computing velocity fields in ice sheets using the principle of mass conservation, and show that, for suitable smoothing of flow directions, the velocity converges to a unique solution under grid refinement. We use this method as the forward model in a constrained optimization problem, and use these so-called balance velocities to seamlessly fill in gaps between satellite-based velocity observations.
D. J. Brinkerhoff and J. V. Johnson
The Cryosphere, 7, 1161–1184, https://doi.org/10.5194/tc-7-1161-2013, https://doi.org/10.5194/tc-7-1161-2013, 2013
Joseph A. MacGregor, Mark A. Fahnestock, John D. Paden, Jilu Li, Jeremy P. Harbeck, and Andy Aschwanden
Earth Syst. Sci. Data, 17, 2911–2931, https://doi.org/10.5194/essd-17-2911-2025, https://doi.org/10.5194/essd-17-2911-2025, 2025
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Understanding glacier mass changes is crucial for assessing freshwater availability in many regions of the world. We present the Mass Balance Machine, a machine learning model that learns from sparse measurements of glacier mass change to make predictions on unmonitored glaciers. Using data from Norway, we show that the model provides accurate estimates of mass changes at different spatiotemporal scales. Our findings show that machine learning can be a valuable tool to improve such predictions.
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The Cryosphere, 19, 1085–1102, https://doi.org/10.5194/tc-19-1085-2025, https://doi.org/10.5194/tc-19-1085-2025, 2025
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Alex S. Gardner, Chad A. Greene, Joseph H. Kennedy, Mark A. Fahnestock, Maria Liukis, Luis A. López, Yang Lei, Ted A. Scambos, and Amaury Dehecq
EGUsphere, https://doi.org/10.5194/egusphere-2025-392, https://doi.org/10.5194/egusphere-2025-392, 2025
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The NASA MEaSUREs Inter-mission Time Series of Land Ice Velocity and Elevation (ITS_LIVE) project provides glacier and ice sheet velocity products for the full Landsat, Sentinel-1 and Sentinel-2 satellite archives, and will soon include data from Sentinel 1C and NISAR satellites. This paper describes the ITS_LIVE processing chain and provides guidance for working with the cloud-optimized velocity data it produces.
Lora May, Svetlana Stuefer, Scott Goddard, and Christopher Larsen
EGUsphere, https://doi.org/10.5194/egusphere-2024-4042, https://doi.org/10.5194/egusphere-2024-4042, 2025
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We contribute to limited boreal forest snow remote sensing research by analyzing field snow depth and airborne lidar data. Two new lidar snow depth and canopy height products are evaluated for application at a boreal forest site in Alaska. Our results show that airborne lidar can effectively estimate snow depths in the boreal forest, should be validated and assessed for errors using ground-based measurements, and can assist water and resource managers in estimating snow depth in boreal forests.
Amy Jenson, Mark Skidmore, Lucas Beem, Martin Truffer, and Scott McCalla
The Cryosphere, 18, 5451–5464, https://doi.org/10.5194/tc-18-5451-2024, https://doi.org/10.5194/tc-18-5451-2024, 2024
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Water in some glacier environments contains salt, which increases its density and lowers its freezing point, allowing saline water to exist where freshwater cannot. Previous subglacial hydrology models do not consider saline fluid. We model the flow of saline fluid from a subglacial lake through a circular channel at the glacier bed, finding that higher salinities lead to less melting at the channel walls and lower discharge rates. We also observe the impact of increased fluid density on flow.
Gabriela Collao-Barrios, Ted A. Scambos, Christian T. Wild, Martin Truffer, Karen E. Alley, and Erin C. Pettit
EGUsphere, https://doi.org/10.5194/egusphere-2024-1895, https://doi.org/10.5194/egusphere-2024-1895, 2024
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Destabilization of ice shelves frequently leads to significant acceleration and greater mass loss, affecting rates of sea level rise. Our results show a relation between tides, flow direction, and grounding-zone acceleration that result from changing stresses in the ice margins and around a nunatak in Dotson Ice Shelf. The study describes a new way tides can influence ice shelf dynamics, an effect that could become more common as ice shelves thin and weaken around Antarctica.
Eric Petersen, Regine Hock, and Michael G. Loso
Earth Surf. Dynam., 12, 727–745, https://doi.org/10.5194/esurf-12-727-2024, https://doi.org/10.5194/esurf-12-727-2024, 2024
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Ice cliffs are melt hot spots that increase melt rates on debris-covered glaciers which otherwise see a reduction in melt rates. In this study, we show how surface runoff streams contribute to the generation, evolution, and survival of ice cliffs by carving into the glacier and transporting rocky debris. On Kennicott Glacier, Alaska, 33 % of ice cliffs are actively influenced by streams, while nearly half are within 10 m of streams.
Naomi E. Ochwat, Ted A. Scambos, Alison F. Banwell, Robert S. Anderson, Michelle L. Maclennan, Ghislain Picard, Julia A. Shates, Sebastian Marinsek, Liliana Margonari, Martin Truffer, and Erin C. Pettit
The Cryosphere, 18, 1709–1731, https://doi.org/10.5194/tc-18-1709-2024, https://doi.org/10.5194/tc-18-1709-2024, 2024
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On the Antarctic Peninsula, there is a small bay that had sea ice fastened to the shoreline (
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Marin Kneib, Evan S. Miles, Pascal Buri, Stefan Fugger, Michael McCarthy, Thomas E. Shaw, Zhao Chuanxi, Martin Truffer, Matthew J. Westoby, Wei Yang, and Francesca Pellicciotti
The Cryosphere, 16, 4701–4725, https://doi.org/10.5194/tc-16-4701-2022, https://doi.org/10.5194/tc-16-4701-2022, 2022
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Ice cliffs are believed to be important contributors to the melt of debris-covered glaciers, but this has rarely been quantified as the cliffs can disappear or rapidly expand within a few weeks. We used photogrammetry techniques to quantify the weekly evolution and melt of four cliffs. We found that their behaviour and melt during the monsoon is strongly controlled by supraglacial debris, streams and ponds, thus providing valuable insights on the melt and evolution of debris-covered glaciers.
Joseph A. MacGregor, Winnie Chu, William T. Colgan, Mark A. Fahnestock, Denis Felikson, Nanna B. Karlsson, Sophie M. J. Nowicki, and Michael Studinger
The Cryosphere, 16, 3033–3049, https://doi.org/10.5194/tc-16-3033-2022, https://doi.org/10.5194/tc-16-3033-2022, 2022
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Where the bottom of the Greenland Ice Sheet is frozen and where it is thawed is not well known, yet knowing this state is increasingly important to interpret modern changes in ice flow there. We produced a second synthesis of knowledge of the basal thermal state of the ice sheet using airborne and satellite observations and numerical models. About one-third of the ice sheet’s bed is likely thawed; two-fifths is likely frozen; and the remainder is too uncertain to specify.
Christian T. Wild, Karen E. Alley, Atsuhiro Muto, Martin Truffer, Ted A. Scambos, and Erin C. Pettit
The Cryosphere, 16, 397–417, https://doi.org/10.5194/tc-16-397-2022, https://doi.org/10.5194/tc-16-397-2022, 2022
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Thwaites Glacier has the potential to significantly raise Antarctica's contribution to global sea-level rise by the end of this century. Here, we use satellite measurements of surface elevation to show that its floating part is close to losing contact with an underwater ridge that currently acts to stabilize. We then use computer models of ice flow to simulate the predicted unpinning, which show that accelerated ice discharge into the ocean follows the breakup of the floating part.
Thiago Dias dos Santos, Mathieu Morlighem, and Douglas Brinkerhoff
The Cryosphere, 16, 179–195, https://doi.org/10.5194/tc-16-179-2022, https://doi.org/10.5194/tc-16-179-2022, 2022
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Projecting the future evolution of Greenland and Antarctica and their potential contribution to sea level rise often relies on computer simulations carried out by numerical ice sheet models. Here we present a new vertically integrated ice sheet model and assess its performance using different benchmarks. The new model shows results comparable to a three-dimensional model at relatively lower computational cost, suggesting that it is an excellent alternative for long-term simulations.
Andy Aschwanden, Timothy C. Bartholomaus, Douglas J. Brinkerhoff, and Martin Truffer
The Cryosphere, 15, 5705–5715, https://doi.org/10.5194/tc-15-5705-2021, https://doi.org/10.5194/tc-15-5705-2021, 2021
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Estimating how much ice loss from Greenland and Antarctica will contribute to sea level rise is of critical societal importance. However, our analysis shows that recent efforts are not trustworthy because the models fail at reproducing contemporary ice melt. Here we present a roadmap towards making more credible estimates of ice sheet melt.
Karen E. Alley, Christian T. Wild, Adrian Luckman, Ted A. Scambos, Martin Truffer, Erin C. Pettit, Atsuhiro Muto, Bruce Wallin, Marin Klinger, Tyler Sutterley, Sarah F. Child, Cyrus Hulen, Jan T. M. Lenaerts, Michelle Maclennan, Eric Keenan, and Devon Dunmire
The Cryosphere, 15, 5187–5203, https://doi.org/10.5194/tc-15-5187-2021, https://doi.org/10.5194/tc-15-5187-2021, 2021
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We present a 20-year, satellite-based record of velocity and thickness change on the Thwaites Eastern Ice Shelf (TEIS), the largest remaining floating extension of Thwaites Glacier (TG). TG holds the single greatest control on sea-level rise over the next few centuries, so it is important to understand changes on the TEIS, which controls much of TG's flow into the ocean. Our results suggest that the TEIS is progressively destabilizing and is likely to disintegrate over the next few decades.
Ellie Broadman, Lorna L. Thurston, Erik Schiefer, Nicholas P. McKay, David Fortin, Jason Geck, Michael G. Loso, Matt Nolan, Stéphanie H. Arcusa, Christopher W. Benson, Rebecca A. Ellerbroek, Michael P. Erb, Cody C. Routson, Charlotte Wiman, A. Jade Wong, and Darrell S. Kaufman
Earth Syst. Sci. Data, 11, 1957–1970, https://doi.org/10.5194/essd-11-1957-2019, https://doi.org/10.5194/essd-11-1957-2019, 2019
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Rapid climate warming is impacting physical processes in Arctic environments. Glacier–fed lakes are influenced by many of these processes, and they are impacted by the changing behavior of weather, glaciers, and rivers. We present data from weather stations, river gauging stations, lake moorings, and more, following 4 years of environmental monitoring in the watershed of Lake Peters, a glacier–fed lake in Arctic Alaska. These data can help us study the changing dynamics of this remote setting.
Nick Rutter, Melody J. Sandells, Chris Derksen, Joshua King, Peter Toose, Leanne Wake, Tom Watts, Richard Essery, Alexandre Roy, Alain Royer, Philip Marsh, Chris Larsen, and Matthew Sturm
The Cryosphere, 13, 3045–3059, https://doi.org/10.5194/tc-13-3045-2019, https://doi.org/10.5194/tc-13-3045-2019, 2019
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Impact of natural variability in Arctic tundra snow microstructural characteristics on the capacity to estimate snow water equivalent (SWE) from Ku-band radar was assessed. Median values of metrics quantifying snow microstructure adequately characterise differences between snowpack layers. Optimal estimates of SWE required microstructural values slightly less than the measured median but tolerated natural variability for accurate estimation of SWE in shallow snowpacks.
Bas Altena, Ted Scambos, Mark Fahnestock, and Andreas Kääb
The Cryosphere, 13, 795–814, https://doi.org/10.5194/tc-13-795-2019, https://doi.org/10.5194/tc-13-795-2019, 2019
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Many glaciers in southern Alaska and the Yukon experience changes in flow speed, which occur in episodes or sporadically. These flow changes can be measured with satellites, but the resulting raw velocity products are messy. Thus in this study we developed an automatic method to produce a synthesized velocity product over a large glacier region of roughly 600 km by 200 km. Velocities are at a monthly resolution and at 300 m resolution, making all kinds of glacier dynamics observable.
Kelly M. Brunt, Thomas A. Neumann, and Christopher F. Larsen
The Cryosphere, 13, 579–590, https://doi.org/10.5194/tc-13-579-2019, https://doi.org/10.5194/tc-13-579-2019, 2019
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This paper provides an assessment of new GPS elevation data collected near the South Pole, Antarctica, that will ultimately be used for ICESat-2 satellite elevation data validation. Further, using the new ground-based GPS data, this paper provides an assessment of airborne lidar elevation data collected between 2014 and 2017, which will also be used for ICESat-2 data validation.
Kang Wang, Elchin Jafarov, Irina Overeem, Vladimir Romanovsky, Kevin Schaefer, Gary Clow, Frank Urban, William Cable, Mark Piper, Christopher Schwalm, Tingjun Zhang, Alexander Kholodov, Pamela Sousanes, Michael Loso, and Kenneth Hill
Earth Syst. Sci. Data, 10, 2311–2328, https://doi.org/10.5194/essd-10-2311-2018, https://doi.org/10.5194/essd-10-2311-2018, 2018
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Ground thermal and moisture data are important indicators of the rapid permafrost changes in the Arctic. To better understand the changes, we need a comprehensive dataset across various sites. We synthesize permafrost-related data in the state of Alaska. It should be a valuable permafrost dataset that is worth maintaining in the future. On a wider level, it also provides a prototype of basic data collection and management for permafrost regions in general.
Etienne Berthier, Christopher Larsen, William J. Durkin, Michael J. Willis, and Matthew E. Pritchard
The Cryosphere, 12, 1523–1530, https://doi.org/10.5194/tc-12-1523-2018, https://doi.org/10.5194/tc-12-1523-2018, 2018
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Two recent studies suggested a slowdown in mass loss after 2000 of the Juneau and Stikine icefields, accounting for 10% of the total ice cover in Alaska. Here, the ASTER-based geodetic mass balances are revisited, carefully avoiding the use of the SRTM DEM, because of the unknown penetration depth of the SRTM C-band radar signal. We find strongly negative mass balances from 2000 to 2016 for both icefields, in agreement with airborne laser altimetry. Mass losses are thus continuing unabated.
Alex S. Gardner, Geir Moholdt, Ted Scambos, Mark Fahnstock, Stefan Ligtenberg, Michiel van den Broeke, and Johan Nilsson
The Cryosphere, 12, 521–547, https://doi.org/10.5194/tc-12-521-2018, https://doi.org/10.5194/tc-12-521-2018, 2018
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We map present-day Antarctic surface velocities from Landsat imagery and compare to earlier estimates from radar. Flow accelerations across the grounding lines of West Antarctica's Amundsen Sea Embayment, Getz Ice Shelf and the western Antarctic Peninsula, account for 89 % of the observed increase in ice discharge. In contrast, glaciers draining the East Antarctic have been remarkably stable. Our work suggests that patterns of mass loss are part of a longer-term phase of enhanced flow.
D. Brinkerhoff and J. Johnson
Geosci. Model Dev., 8, 1275–1283, https://doi.org/10.5194/gmd-8-1275-2015, https://doi.org/10.5194/gmd-8-1275-2015, 2015
Short summary
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We present a novel numerical method for computing velocity fields in ice sheets using the principle of mass conservation, and show that, for suitable smoothing of flow directions, the velocity converges to a unique solution under grid refinement. We use this method as the forward model in a constrained optimization problem, and use these so-called balance velocities to seamlessly fill in gaps between satellite-based velocity observations.
D. J. Brinkerhoff and J. V. Johnson
The Cryosphere, 7, 1161–1184, https://doi.org/10.5194/tc-7-1161-2013, https://doi.org/10.5194/tc-7-1161-2013, 2013
Related subject area
Discipline: Glaciers | Subject: Numerical Modelling
Inter-model differences in 21st century glacier runoff for the world's major river basins
A minimal machine-learning glacier mass balance model
Physically based modelling of glacier evolution under climate change in the tropical Andes
New glacier thickness and bed topography maps for Svalbard
Sea-level rise contribution from Ryder Glacier in Northern Greenland varies by an order of magnitude by 2300 depending on future emissions
Quantifying the buttressing contribution of landfast sea ice and melange to Crane Glacier, Antarctic Peninsula
Application of a regularised Coulomb sliding law to Jakobshavn Isbræ, western Greenland
Increasing numerical stability of mountain valley glacier simulations: implementation and testing of free-surface stabilization in Elmer/Ice
A 3D glacier dynamics–line plume model to estimate the frontal ablation of Hansbreen, Svalbard
Decadal re-forecasts of glacier climatic mass balance
Impact of the Nares Strait sea ice arches on the long-term stability of the Petermann Glacier ice shelf
Reconciling ice dynamics and bed topography with a versatile and fast ice thickness inversion
Exploring the ability of the variable-resolution Community Earth System Model to simulate cryospheric–hydrological variables in High Mountain Asia
Modelling the development and decay of cryoconite holes in northwestern Greenland
Thermal regime of the Grigoriev ice cap and the Sary-Tor glacier in the inner Tien Shan, Kyrgyzstan
Modelling supraglacial debris-cover evolution from the single-glacier to the regional scale: an application to High Mountain Asia
The 21st-century fate of the Mocho-Choshuenco ice cap in southern Chile
Modelling steady states and the transient response of debris-covered glaciers
Twentieth century global glacier mass change: an ensemble-based model reconstruction
Mapping the age of ice of Gauligletscher combining surface radionuclide contamination and ice flow modeling
Modelling the evolution of Djankuat Glacier, North Caucasus, from 1752 until 2100 CE
Brief communication: Time step dependence (and fixes) in Stokes simulations of calving ice shelves
Modelling regional glacier length changes over the last millennium using the Open Global Glacier Model
The contrasting response of outlet glaciers to interior and ocean forcing
Deep learning applied to glacier evolution modelling
Initialization of a global glacier model based on present-day glacier geometry and past climate information: an ensemble approach
Contrasting thinning patterns between lake- and land-terminating glaciers in the Bhutanese Himalaya
Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska
Modeling the response of Greenland outlet glaciers to global warming using a coupled flow line–plume model
Buoyant forces promote tidewater glacier iceberg calving through large basal stress concentrations
Global glacier volume projections under high-end climate change scenarios
Finn Wimberly, Lizz Ultee, Lilian Schuster, Matthias Huss, David R. Rounce, Fabien Maussion, Sloan Coats, Jonathan Mackay, and Erik Holmgren
The Cryosphere, 19, 1491–1511, https://doi.org/10.5194/tc-19-1491-2025, https://doi.org/10.5194/tc-19-1491-2025, 2025
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Glacier models have historically been used to understand glacier melt’s contribution to sea level rise. The capacity to project seasonal glacier runoff is a relatively recent development for these models. In this study we provide the first model intercomparison of runoff projections for the glacier evolution models capable of simulating future runoff globally. We compare model projections from 2000 to 2100 for all major river basins larger than 3000 km2 with over 30 km2 of initial glacier cover.
Marijn van der Meer, Harry Zekollari, Matthias Huss, Jordi Bolibar, Kamilla Hauknes Sjursen, and Daniel Farinotti
The Cryosphere, 19, 805–826, https://doi.org/10.5194/tc-19-805-2025, https://doi.org/10.5194/tc-19-805-2025, 2025
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Glacier retreat poses big challenges, making understanding how climate affects glaciers vital. But glacier measurements worldwide are limited. We created a simple machine-learning model called miniML-MB, which estimates annual changes in glacier mass in the Swiss Alps. As input, miniML-MB uses two climate variables: average temperature (May–Aug) and total precipitation (Oct–Feb). Our model can accurately predict glacier mass from 1961 to 2021 but struggles for extreme years (2022 and 2023).
Jonathan D. Mackay, Nicholas E. Barrand, David M. Hannah, Emily Potter, Nilton Montoya, and Wouter Buytaert
The Cryosphere, 19, 685–712, https://doi.org/10.5194/tc-19-685-2025, https://doi.org/10.5194/tc-19-685-2025, 2025
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We combine two globally capable glacier evolution models to include processes that are typically neglected but thought to control tropical glacier retreat (e.g. sublimation). We apply the model to Peru's Vilcanota-Urubamba Basin. The model captures observed glacier mass changes,but struggles with surface albedo dynamics. Projections show glacier mass shrinking to 17 % or 6 % of 2000 levels by 2100 under moderate- and high-emission scenarios, respectively.
Ward van Pelt and Thomas Frank
The Cryosphere, 19, 1–17, https://doi.org/10.5194/tc-19-1-2025, https://doi.org/10.5194/tc-19-1-2025, 2025
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Accurate information on the ice thickness of Svalbard's glaciers is important for assessing the contribution to sea level rise in a present and a future climate. However, direct observations of the glacier bed are scarce. Here, we use an inverse approach and high-resolution surface observations to infer basal conditions. We present and analyse the new bed and thickness maps, quantify the ice volume (6800 km3), and compare these against radar data and previous studies.
Felicity Alice Holmes, Jamie Barnett, Henning Åkesson, Mathieu Morlighem, Johan Nilsson, Nina Kirchner, and Martin Jakobsson
EGUsphere, https://doi.org/10.5194/egusphere-2024-3839, https://doi.org/10.5194/egusphere-2024-3839, 2024
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Northern Greenland contains some of the ice sheet's last remaining glaciers with floating ice tongues. One of these is Ryder Glacier, which has been relatively stable in recent decades in contrast to nearby glaciers. Here, we use a computer model to simulate Ryder Glacier until 2300 under both a low and high emissions scenario. Very high levels of surface melt under a high emissions future leads to a sea-level rise contribution an order of magnitude higher than under a low emissions future.
Richard Parsons, Sainan Sun, G. Hilmar Gudmundsson, Jan Wuite, and Thomas Nagler
The Cryosphere, 18, 5789–5801, https://doi.org/10.5194/tc-18-5789-2024, https://doi.org/10.5194/tc-18-5789-2024, 2024
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In 2022, multi-year landfast sea ice in Antarctica's Larsen B embayment disintegrated, after which time an increase in the rate at which Crane Glacier discharged ice into the ocean was observed. As the fast ice was joined to the glacier terminus, it could provide resistance against the glacier's flow, slowing down the rate of ice discharge. We used numerical modelling to quantify this resistive stress and found that the fast ice provided significant support to Crane prior to its disintegration.
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
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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.
André Löfgren, Thomas Zwinger, Peter Råback, Christian Helanow, and Josefin Ahlkrona
The Cryosphere, 18, 3453–3470, https://doi.org/10.5194/tc-18-3453-2024, https://doi.org/10.5194/tc-18-3453-2024, 2024
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This paper investigates a stabilization method for free-surface flows in the context of glacier simulations. Previous applications of the stabilization on ice flows have only considered simple ice-sheet benchmark problems; in particular the method had not been tested on real-world glacier domains. This work addresses this shortcoming by demonstrating that the stabilization works well also in this case and increases stability and robustness without negatively impacting computation times.
José M. Muñoz-Hermosilla, Jaime Otero, Eva De Andrés, Kaian Shahateet, Francisco Navarro, and Iván Pérez-Doña
The Cryosphere, 18, 1911–1924, https://doi.org/10.5194/tc-18-1911-2024, https://doi.org/10.5194/tc-18-1911-2024, 2024
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A large fraction of the mass loss from marine-terminating glaciers is attributed to frontal ablation. In this study, we used a 3D ice flow model of a real glacier that includes the effects of calving and submarine melting. Over a 30-month simulation, we found that the model reproduced the seasonal cycle for this glacier. Besides, the front positions were in good agreement with observations in the central part of the front, with longitudinal differences, on average, below 15 m.
Larissa van der Laan, Anouk Vlug, Adam A. Scaife, Fabien Maussion, and Kristian Förster
EGUsphere, https://doi.org/10.5194/egusphere-2024-387, https://doi.org/10.5194/egusphere-2024-387, 2024
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Usually, glacier models are supplied with climate information from long (e.g. 100 year) simulations by global climate models. In this paper, we test the feasibility of supplying glacier models with shorter simulations, to get more accurate information on 5–10 year time scales. Reliable information on these time scales is very important, especially for water management experts to know how much meltwater to expect, for rivers, agriculture and drinking water.
Abhay Prakash, Qin Zhou, Tore Hattermann, and Nina Kirchner
The Cryosphere, 17, 5255–5281, https://doi.org/10.5194/tc-17-5255-2023, https://doi.org/10.5194/tc-17-5255-2023, 2023
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Sea ice arch formation in the Nares Strait has shielded the Petermann Glacier ice shelf from enhanced basal melting. However, with the sustained decline of the Arctic sea ice predicted to continue, the ice shelf is likely to be exposed to a year-round mobile and thin sea ice cover. In such a scenario, our modelled results show that elevated temperatures, and more importantly, a stronger ocean circulation in the ice shelf cavity, could result in up to two-thirds increase in basal melt.
Thomas Frank, Ward J. J. van Pelt, and Jack Kohler
The Cryosphere, 17, 4021–4045, https://doi.org/10.5194/tc-17-4021-2023, https://doi.org/10.5194/tc-17-4021-2023, 2023
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Since the ice thickness of most glaciers worldwide is unknown, and since it is not feasible to visit every glacier and observe their thickness directly, inverse modelling techniques are needed that can calculate ice thickness from abundant surface observations. Here, we present a new method for doing that. Our methodology relies on modelling the rate of surface elevation change for a given glacier, compare this with observations of the same quantity and change the bed until the two are in line.
René R. Wijngaard, Adam R. Herrington, William H. Lipscomb, Gunter R. Leguy, and Soon-Il An
The Cryosphere, 17, 3803–3828, https://doi.org/10.5194/tc-17-3803-2023, https://doi.org/10.5194/tc-17-3803-2023, 2023
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We evaluate the ability of the Community Earth System Model (CESM2) to simulate cryospheric–hydrological variables, such as glacier surface mass balance (SMB), over High Mountain Asia (HMA) by using a global grid (~111 km) with regional refinement (~7 km) over HMA. Evaluations of two different simulations show that climatological biases are reduced, and glacier SMB is improved (but still too negative) by modifying the snow and glacier model and using an updated glacier cover dataset.
Yukihiko Onuma, Koji Fujita, Nozomu Takeuchi, Masashi Niwano, and Teruo Aoki
The Cryosphere, 17, 3309–3328, https://doi.org/10.5194/tc-17-3309-2023, https://doi.org/10.5194/tc-17-3309-2023, 2023
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We established a novel model that simulates the temporal changes in cryoconite hole (CH) depth using heat budgets calculated independently at the ice surface and CH bottom based on hole shape geometry. The simulations suggest that CH depth is governed by the balance between the intensity of the diffuse component of downward shortwave radiation and the wind speed. The meteorological conditions may be important factors contributing to the recent ice surface darkening via the redistribution of CHs.
Lander Van Tricht and Philippe Huybrechts
The Cryosphere, 16, 4513–4535, https://doi.org/10.5194/tc-16-4513-2022, https://doi.org/10.5194/tc-16-4513-2022, 2022
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We examine the thermal regime of the Grigoriev ice cap and the Sary-Tor glacier, both located in the inner Tien Shan in Kyrgyzstan. Our findings are important as the ice dynamics can only be understood and modelled precisely if ice temperature is considered correctly in ice flow models. The calibrated parameters of this study can be used in applications with ice flow models for individual ice masses as well as to optimise more general models for large-scale regional simulations.
Loris Compagno, Matthias Huss, Evan Stewart Miles, Michael James McCarthy, Harry Zekollari, Amaury Dehecq, Francesca Pellicciotti, and Daniel Farinotti
The Cryosphere, 16, 1697–1718, https://doi.org/10.5194/tc-16-1697-2022, https://doi.org/10.5194/tc-16-1697-2022, 2022
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We present a new approach for modelling debris area and thickness evolution. We implement the module into a combined mass-balance ice-flow model, and we apply it using different climate scenarios to project the future evolution of all glaciers in High Mountain Asia. We show that glacier geometry, volume, and flow velocity evolve differently when modelling explicitly debris cover compared to glacier evolution without the debris-cover module, demonstrating the importance of accounting for debris.
Matthias Scheiter, Marius Schaefer, Eduardo Flández, Deniz Bozkurt, and Ralf Greve
The Cryosphere, 15, 3637–3654, https://doi.org/10.5194/tc-15-3637-2021, https://doi.org/10.5194/tc-15-3637-2021, 2021
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We simulate the current state and future evolution of the Mocho-Choshuenco ice cap in southern Chile (40°S, 72°W) with the ice-sheet model SICOPOLIS. Under different global warming scenarios, we project ice mass losses between 56 % and 97 % by the end of the 21st century. We quantify the uncertainties based on an ensemble of climate models and on the temperature dependence of the equilibrium line altitude. Our results suggest a considerable deglaciation in southern Chile in the next 80 years.
James C. Ferguson and Andreas Vieli
The Cryosphere, 15, 3377–3399, https://doi.org/10.5194/tc-15-3377-2021, https://doi.org/10.5194/tc-15-3377-2021, 2021
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Debris-covered glaciers have a greater extent than their debris-free counterparts due to insulation from the debris cover. However, the transient response to climate change remains poorly understood. We use a numerical model that couples ice dynamics and debris transport and varies the climate signal. We find that debris cover delays the transient response, especially for the extent. However, adding cryokarst features near the terminus greatly enhances the response.
Jan-Hendrik Malles and Ben Marzeion
The Cryosphere, 15, 3135–3157, https://doi.org/10.5194/tc-15-3135-2021, https://doi.org/10.5194/tc-15-3135-2021, 2021
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To better estimate the uncertainty in glacier mass change modeling during the 20th century we ran an established model with an ensemble of meteorological data sets. We find that the total ensemble uncertainty, especially in the early 20th century, when glaciological and meteorological observations at glacier locations were sparse, increases considerably compared to individual ensemble runs. This stems from regions with a lot of ice mass but few observations (e.g., Greenland periphery).
Guillaume Jouvet, Stefan Röllin, Hans Sahli, José Corcho, Lars Gnägi, Loris Compagno, Dominik Sidler, Margit Schwikowski, Andreas Bauder, and Martin Funk
The Cryosphere, 14, 4233–4251, https://doi.org/10.5194/tc-14-4233-2020, https://doi.org/10.5194/tc-14-4233-2020, 2020
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We show that plutonium is an effective tracer to identify ice originating from the early 1960s at the surface of a mountain glacier after a long time within the ice flow, giving unique information on the long-term former ice motion. Combined with ice flow modelling, the dating can be extended to the entire glacier, and we show that an airplane which crash-landed on the Gauligletscher in 1946 will likely soon be released from the ice close to the place where pieces have emerged in recent years.
Yoni Verhaegen, Philippe Huybrechts, Oleg Rybak, and Victor V. Popovnin
The Cryosphere, 14, 4039–4061, https://doi.org/10.5194/tc-14-4039-2020, https://doi.org/10.5194/tc-14-4039-2020, 2020
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We use a numerical flow model to simulate the behaviour of the Djankuat Glacier, a WGMS reference glacier situated in the North Caucasus (Republic of Kabardino-Balkaria, Russian Federation), in response to past, present and future climate conditions (1752–2100 CE). In particular, we adapt a more sophisticated and physically based debris model, which has not been previously applied in time-dependent numerical flow line models, to look at the impact of a debris cover on the glacier’s evolution.
Brandon Berg and Jeremy Bassis
The Cryosphere, 14, 3209–3213, https://doi.org/10.5194/tc-14-3209-2020, https://doi.org/10.5194/tc-14-3209-2020, 2020
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Computer models of ice sheets and glaciers are an important component of projecting sea level rise due to climate change. For models that seek to simulate the full balance of forces within the ice, if portions of the glacier are allowed to quickly break off in a process called iceberg calving, a numerical issue arises that can cause inaccurate results. We examine the issue and propose a solution so that future models can more accurately predict the future behavior of ice sheets and glaciers.
David Parkes and Hugues Goosse
The Cryosphere, 14, 3135–3153, https://doi.org/10.5194/tc-14-3135-2020, https://doi.org/10.5194/tc-14-3135-2020, 2020
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Direct records of glacier changes rarely go back more than the last 100 years and are few and far between. We used a sophisticated glacier model to simulate glacier length changes over the last 1000 years for those glaciers that we do have long-term records of, to determine whether the model can run in a stable, realistic way over a long timescale, reproducing recent observed trends. We find that post-industrial changes are larger than other changes in this time period driven by recent warming.
John Erich Christian, Alexander A. Robel, Cristian Proistosescu, Gerard Roe, Michelle Koutnik, and Knut Christianson
The Cryosphere, 14, 2515–2535, https://doi.org/10.5194/tc-14-2515-2020, https://doi.org/10.5194/tc-14-2515-2020, 2020
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We use simple, physics-based models to compare how marine-terminating glaciers respond to changes at their marine margin vs. inland surface melt. Initial glacier retreat is more rapid for ocean changes than for inland changes, but in both cases, glaciers will continue responding for millennia. We analyze several implications of these differing pathways of change. In particular, natural ocean variability must be better understood to correctly identify the anthropogenic role in glacier retreat.
Jordi Bolibar, Antoine Rabatel, Isabelle Gouttevin, Clovis Galiez, Thomas Condom, and Eric Sauquet
The Cryosphere, 14, 565–584, https://doi.org/10.5194/tc-14-565-2020, https://doi.org/10.5194/tc-14-565-2020, 2020
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We introduce a novel approach for simulating glacier mass balances using a deep artificial neural network (i.e. deep learning) from climate and topographical data. This has been added as a component of a new open-source parameterized glacier evolution model. Deep learning is found to outperform linear machine learning methods, mainly due to its nonlinearity. Potential applications range from regional mass balance reconstructions from observations to simulations for past and future climates.
Julia Eis, Fabien Maussion, and Ben Marzeion
The Cryosphere, 13, 3317–3335, https://doi.org/10.5194/tc-13-3317-2019, https://doi.org/10.5194/tc-13-3317-2019, 2019
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To provide estimates of past glacier mass changes, an adequate initial state is required. However, information about past glacier states at regional or global scales is largely incomplete. Our study presents a new way to initialize the Open Global Glacier Model from past climate information and present-day geometries. We show that even with perfectly known but incomplete boundary conditions, the problem of model initialization leads to nonunique solutions, and we propose an ensemble approach.
Shun Tsutaki, Koji Fujita, Takayuki Nuimura, Akiko Sakai, Shin Sugiyama, Jiro Komori, and Phuntsho Tshering
The Cryosphere, 13, 2733–2750, https://doi.org/10.5194/tc-13-2733-2019, https://doi.org/10.5194/tc-13-2733-2019, 2019
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We investigate thickness change of Bhutanese glaciers during 2004–2011 using repeat GPS surveys and satellite-based observations. The thinning rate of Lugge Glacier (LG) is > 3 times that of Thorthormi Glacier (TG). Numerical simulations of ice dynamics and surface mass balance (SMB) demonstrate that the rapid thinning of LG is driven by both negative SMB and dynamic thinning, while the thinning of TG is minimised by a longitudinally compressive flow regime.
Beatriz Recinos, Fabien Maussion, Timo Rothenpieler, and Ben Marzeion
The Cryosphere, 13, 2657–2672, https://doi.org/10.5194/tc-13-2657-2019, https://doi.org/10.5194/tc-13-2657-2019, 2019
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We have implemented a frontal ablation parameterization into the Open Global Glacier Model and have shown that inversion methods based on mass conservation systematically underestimate the mass turnover (and therefore the thickness) of tidewater glaciers when neglecting frontal ablation. This underestimation can rise up to 19 % on a regional scale. Not accounting for frontal ablation will have an impact on the estimate of the glaciers’ potential contribution to sea level rise.
Johanna Beckmann, Mahé Perrette, Sebastian Beyer, Reinhard Calov, Matteo Willeit, and Andrey Ganopolski
The Cryosphere, 13, 2281–2301, https://doi.org/10.5194/tc-13-2281-2019, https://doi.org/10.5194/tc-13-2281-2019, 2019
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Submarine melting (SM) has been discussed as potentially triggering the recently observed retreat at outlet glaciers in Greenland. How much it may contribute in terms of future sea level rise (SLR) has not been quantified yet. When accounting for SM in our experiments, SLR contribution of 12 outlet glaciers increases by over 3-fold until the year 2100 under RCP8.5. Scaling up from 12 to all of Greenland's outlet glaciers increases future SLR contribution of Greenland by 50 %.
Matt Trevers, Antony J. Payne, Stephen L. Cornford, and Twila Moon
The Cryosphere, 13, 1877–1887, https://doi.org/10.5194/tc-13-1877-2019, https://doi.org/10.5194/tc-13-1877-2019, 2019
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Iceberg calving is a major factor in the retreat of outlet glaciers of the Greenland Ice Sheet. Massive block overturning calving events occur at major outlet glaciers. A major calving event in 2009 was triggered by the release of a smaller block of ice from above the waterline. Using a numerical model, we investigate the feasibility of this mechanism to drive large calving events. We find that relatively small perturbations induce forces large enough to open cracks in ice at the glacier bed.
Sarah Shannon, Robin Smith, Andy Wiltshire, Tony Payne, Matthias Huss, Richard Betts, John Caesar, Aris Koutroulis, Darren Jones, and Stephan Harrison
The Cryosphere, 13, 325–350, https://doi.org/10.5194/tc-13-325-2019, https://doi.org/10.5194/tc-13-325-2019, 2019
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We present global glacier volume projections for the end of this century, under a range of high-end climate change scenarios, defined as exceeding 2 °C global average warming. The ice loss contribution to sea level rise for all glaciers excluding those on the peripheral of the Antarctic ice sheet is 215.2 ± 21.3 mm. Such large ice losses will have consequences for sea level rise and for water supply in glacier-fed river systems.
Cited articles
Arakawa, A. and Lamb, V. R.: Computational design of the basic dynamical processes of the UCLA general circulation model, General circulation models of the atmosphere, Method. Comput. Phys., 17, 173–265, 1977. a
Arendt, A. A., Echelmeyer, K. A., Harrison, W. D., Lingle, C. S., and Valentine, V. B.: Rapid wastage of Alaska glaciers and their contribution to rising sea level, Science, 297, 382–386, 2002. a
Arthern, R. J., Hindmarsh, R. C., 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, 2015. a
Barclay, D. J., Calkin, P. E., and Wiles, G. C.: Holocene history of Hubbard Glacier in Yakutat Bay and Russell Fiord, southern Alaska, Geol. Soc. Am. Bull., 113, 388–402, 2001. a
Blundell, G. M., Womble, J. N., Pendleton, G. W., Karpovich, S. A., Gende, S. M., and Herreman, J. K.: Use of glacial and terrestrial habitats by harbor seals in Glacier Bay, Alaska: costs and benefits, Mar. Ecol. Prog. Ser., 429, 277–290, 2011. a
Boffi, D., Brezzi, F., and Fortin, M.: Mixed finite element methods and applications, Vol. 44, Springer, https://doi.org/10.1007/978-3-642-36519-5, 2013. a
Brinkerhoff, D.: CompatibleElementGlacierModel/ManuscriptCode: Code archive for “The demise of the world's largest piedmont glacier” (v0.2-alpha), Zenodo [code], https://doi.org/10.5281/zenodo.15028564, 2025. a
Brinkerhoff, D., Truffer, M., and Aschwanden, A.: Sediment transport drives tidewater glacier periodicity, Nat. Commun., 8, 90, https://doi.org/10.1038/s41467-017-00095-5, 2017. a, b
Brinkerhoff, D. J.: Variational inference at glacier scale, J. Comput. Phys., 459, 111095, https://doi.org/10.1016/j.jcp.2022.111095, 2022. a
Brinkerhoff, D. J.: Compatible Finite Elements for Glacier Modeling, Comput. Sci. Eng., 25, 18–28, https://doi.org/10.1109/MCSE.2023.3305864, 2023. a, b, c
Budd, W., Keage, P., and Blundy, N.: Empirical studies of ice sliding, J. Glaciol., 23, 157–170, 1979. a
Bueler, E.: Stable finite volume element schemes for the shallow-ice approximation, J. Glaciol., 62, 230–242, 2016. a
Choi, Y., Seroussi, H., Morlighem, M., Schlegel, N.-J., and Gardner, A.: Impact of time-dependent data assimilation on ice flow model initialization and projections: a case study of Kjer Glacier, Greenland, The Cryosphere, 17, 5499–5517, https://doi.org/10.5194/tc-17-5499-2023, 2023. a
Cotton, M. M., Bruhn, R. L., Sauber, J., Burgess, E., and Forster, R. R.: Ice surface morphology and flow on Malaspina Glacier, Alaska: Implications for regional tectonics in the Saint Elias orogen, Tectonics, 33, 581–595, 2014. a
Dias dos Santos, T., Morlighem, M., and Brinkerhoff, D.: A new vertically integrated MOno-Layer Higher-Order (MOLHO) ice flow model, The Cryosphere, 16, 179–195, https://doi.org/10.5194/tc-16-179-2022, 2022. a
European Space Agency: Copernicus DEM – Global and European Digital Elevation Model, Copernicus Data Space Ecosystem, https://doi.org/10.5270/ESA-c5d3d65, 2019. a
Forget, G., Campin, J.-M., Heimbach, P., Hill, C. N., Ponte, R. M., and Wunsch, C.: ECCO version 4: an integrated framework for non-linear inverse modeling and global ocean state estimation, Geosci. Model Dev., 8, 3071–3104, https://doi.org/10.5194/gmd-8-3071-2015, 2015. a
Gardner, A. S., Moholdt, G., Scambos, T., Fahnstock, M., Ligtenberg, S., van den Broeke, M., and Nilsson, J.: Increased West Antarctic and unchanged East Antarctic ice discharge over the last 7 years, The Cryosphere, 12, 521–547, https://doi.org/10.5194/tc-12-521-2018, 2018. a
Goldberg, D. N. and Heimbach, P.: Parameter and state estimation with a time-dependent adjoint marine ice sheet model, The Cryosphere, 7, 1659–1678, https://doi.org/10.5194/tc-7-1659-2013, 2013. 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
Gudmundsson, G. H. and Raymond, M.: On the limit to resolution and information on basal properties obtainable from surface data on ice streams, The Cryosphere, 2, 167–178, https://doi.org/10.5194/tc-2-167-2008, 2008. a
Gudmundsson, G. H., Paolo, F. S., Adusumilli, S., and Fricker, H. A.: Instantaneous Antarctic ice sheet mass loss driven by thinning ice shelves, Geophys. Res. Lett., 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
Halko, N., Martinsson, P.-G., and Tropp, J. A.: Finding structure with randomness: Probabilistic algorithms for constructing approximate matrix decompositions, SIAM Rev., 53, 217–288, 2011. a
Heimbach, P. and Bugnion, V.: Greenland ice-sheet volume sensitivity to basal, surface and initial conditions derived from an adjoint model, Ann. Glaciol., 50, 67–80, 2009. a
Joughin, I., MacAyeal, D. R., and Tulaczyk, S.: Basal shear stress of the Ross ice streams from control method inversions, J. Geophys. Res.-So. Ea., 109, B09405, https://doi.org/10.1029/2003JB002960, 2004. a
Jouvet, G., Cordonnier, G., Kim, B., Lüthi, M., Vieli, A., and Aschwanden, A.: Deep learning speeds up ice flow modelling by several orders of magnitude, J. Glaciol., 68, 651–664, 2022. a
Koziol, C. P., Todd, J. A., Goldberg, D. N., and Maddison, J. R.: fenics_ice 1.0: a framework for quantifying initialization uncertainty for time-dependent ice sheet models, Geosci. Model Dev., 14, 5843–5861, https://doi.org/10.5194/gmd-14-5843-2021, 2021. 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
Larsen, C., Burgess, E., Arendt, A., O'neel, S., Johnson, A., and Kienholz, C.: Surface melt dominates Alaska glacier mass balance, Geophys. Res. Lett., 42, 5902–5908, 2015. a
Lee, J.-Y., Marotzke, J., Bala, G., Cao, L., Corti, S., Dunne, J. P., Engelbrecht, F., Fischer, E., Fyfe, J. C., Jones, C., Maycock, A., Mutemi, J., Ndiaye, O., Panickal, S., and Zhou, T.: Future Global Climate: Scenario-Based Projections and Near-Term Information, in: Climate Change 2021: The Physical Science Basis, Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Masson-Delmotte, V., Zhai, P., Pirani, A., Connors, S. L., Péan, C., Berger, S., Caud, N., Chen, Y., Goldfarb, L., Gomis, M. I., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J. B. R., Maycock, T. K., Waterfield, T., Yelekçi, O., Yu, R., and Zhou, B., 383–588, Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, https://doi.org/10.1017/9781009157896.004, 2021. a
Li, J., Rodriguez-Morales, F., Arnold, E., Leuschen, C., Paden, J., Shang, J., Gomez-Garcia, D., and Larsen, C.: Airborne snow measurements over Alaska mountains and glaciers with a compact FMCW radar, in: IGARSS 2019-2019 IEEE Int. Geosci. Remote Sens. Symposium, Yokohama, Japan, 3906–3909, https://doi.org/10.1109/IGARSS.2019.8900034, 2019. a, b
Lingle, C. S., Post, A., Herzfeld, U. C., Molnia, B. F., Krimmel, R. M., and Roush, J. J.: Bering Glacier surge and iceberg-calving mechanism at Vitus Lake, Alaska, USA, J. Glaciol., 39, 722–727, 1993. a
Magnus, J. R. and Neudecker, H.: Matrix differential calculus with applications in statistics and econometrics, John Wiley & Sons, https://doi.org/10.1002/9781119541219, 2019. a
Mardal, K. A., Tai, X.-C., and Winther, R.: A robust finite element method for Darcy–Stokes flow, SIAM J. Numer. Anal., 40, 1605–1631, 2002. a
Meier, M. and Post, A.: Fast tidewater glaciers, J. Geophys. Res.-Sol. Ea., 92, 9051–9058, 1987. 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, J. Geophys. Res.-Earth, 118, 1746–1753, 2013. a
Motyka, R. J., Truffer, M., Kuriger, E. M., and Bucki, A. K.: Rapid erosion of soft sediments by tidewater glacier advance: Taku Glacier, Alaska, USA, Geophys. Res. Lett., 33, L24504, https://doi.org/10.1029/2006GL028467, 2006. a
Neal, E. G., Hood, E., and Smikrud, K.: Contribution of glacier runoff to freshwater discharge into the Gulf of Alaska, Geophys. Res. Lett., 37, L06404, https://doi.org/10.1029/2010GL042385, 2010. a
Paszke, A., Gross, S., Massa, F., Lerer, A., Bradbury, J., Chanan, G., Killeen, T., Lin, Z., Gimelshein, N., Antiga, L., Desmaison, A., Köpf, A., Yang, E., DeVito, Z., Raison, M., Tejani, A., Chilamkurthy, S., Steiner, B., Fang, L., Bai, J., and Chintala, S.: Pytorch: An imperative style, high-performance deep learning library, Advances in neural information processing systems, 32, 1–12, ISBN: 9781713871088, 2019. a, b
Pattyn, F.: A new three-dimensional higher-order thermomechanical ice sheet model: Basic sensitivity, ice stream development, and ice flow across subglacial lakes, J. Geophys. Res.-Sol. Ea., 108, 2382, https://doi.org/10.1029/2002JB002329, 2003. a
Perego, M., Price, S., and Stadler, G.: Optimal initial conditions for coupling ice sheet models to Earth system models, J. Geophys. Res.-Earth, 119, 1894–1917, 2014. 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, J. Glaciol., 58, 889–903, 2012. a
Petra, N., Martin, J., Stadler, G., and Ghattas, O.: A computational framework for infinite-dimensional Bayesian inverse problems, Part II: Stochastic Newton MCMC with application to ice sheet flow inverse problems, SIAM J. Sci. Comput., 36, A1525–A1555, 2014. 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, J. Glaciol., 67, 229–242, 2021. a
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
Riel, B., Minchew, B., and Bischoff, T.: Data-driven inference of the mechanics of slip along glacier beds using physics-informed neural networks: Case study on Rutford Ice Stream, Antarctica, J. Ad. Model. Earth Sy., 13, e2021MS002621, https://doi.org/10.1029/2021MS002621, 2021. a
Sergienko, O. V. and Hindmarsh, R. C.: Regular patterns in frictional resistance of ice-stream beds seen by surface data inversion, Science, 342, 1086–1089, 2013. a
Smith, R. B. and Barstad, I.: A linear theory of orographic precipitation, J. Atmos. Sci., 61, 1377–1391, 2004. a
Thompson, A., Loso, M., Jones, T., Truffer, M., Holt, J., Devaux-Chupin, V., Tober, B., Christoffersen, M., Kuehn, T., Wagner, N., and Fahnestock, M.: Saltwater Intrusion in Proglacial Lakes at Malaspina Glacier, Southeast Alaska: Introducing the Worlds Newest Tidewater Glacier, in: AGU Fall Meeting Abstracts, Vol. 2021, C13B–07, American Geophysical Union, 2021. a
Thompson, A. C., Loso, M. G., Mooneyham, S. A., Tober, B. S., Larsen, C. F., and Holt, J. W.: Surficial geology and proglacial lake change at Sít’ Tlein (Malaspina Glacier), Wrangell-St. Elias National Park and Preserve, Alaska, Natural Resource Report NPS/WRST/NRR—2024/2620, National Park Service, Fort Collins, Colorado, https://doi.org/10.36967/2301689, 2024. a
Thornton, T. F.: Haa léelk'w hás aaní saax'ú: our grandparents' names on the land, University of Washington Press, ISBN: 9780295988580, 2012. a
Tober, B., Holt, J., Christoffersen, M., Truffer, M., Larsen, C., Brinkerhoff, D., and Mooneyham, S.: Comprehensive Radar Mapping of Malaspina Glacier (Sít' Tlein), Alaska – The World's Largest Piedmont Glacier – Reveals Potential for Instability, J. Geophys. Res.-Earth, 128, e2022JF006898, https://doi.org/10.1029/2022JF006898, 2023. a, b, c, d, e, f
Tropp, J. A., Yurtsever, A., Udell, M., and Cevher, V.: Practical sketching algorithms for low-rank matrix approximation, SIAM J. Matrix Anal. A., 38, 1454–1485, 2017. a
Truffer, M. and Motyka, R. J.: Where glaciers meet water: Subaqueous melt and its relevance to glaciers in various settings, Rev. Geophys., 54, 220–239, 2016. a
Voulgaris, G., Mademlis, I., and Pitas, I.: Procedural terrain generation using generative adversarial networks, in: 2021 29th European Signal Processing Conference (EUSIPCO), 686–690, IEEE, https://doi.org/10.23919/EUSIPCO54536.2021.9616151, 2021. a
Williams, C. K. and Rasmussen, C. E.: Gaussian processes for machine learning, vol. 2, MIT press Cambridge, MA, https://doi.org/10.7551/mitpress/3206.001.0001, 2006. a, b
Wilson, A. and Nickisch, H.: Kernel interpolation for scalable structured Gaussian processes (KISS-GP), in: International conference on machine learning, 1775–1784, PMLR, https://doi.org/10.5555/3045118.3045307, 2015. a, b, c
Zhu, C., Byrd, R. H., Lu, P., and Nocedal, J.: Algorithm 778: L-BFGS-B: Fortran subroutines for large-scale bound-constrained optimization, ACM Transactions on mathematical software (TOMS), 23, 550–560, 1997. a
Short summary
Sít' Tlein is one of the largest glaciers in the world outside of the polar regions, and we know that it has been rapidly thinning. To forecast how this glacier will change in the future, we combine a computer model of ice flow with measurements from many different sources. Our model tells us that with high probability, Sít' Tlein's lower reaches are going to disappear in the next century and a half, creating a new bay or lake along Alaska's coastline.
Sít' Tlein is one of the largest glaciers in the world outside of the polar regions, and we know...
