Articles | Volume 9, issue 6
https://doi.org/10.5194/tc-9-2215-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/tc-9-2215-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Brief communication: Getting Greenland's glaciers right – a new data set of all official Greenlandic glacier names
A. A. Bjørk
Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark
L. M. Kruse
Oqaasileriffik – The Greenland Language Secretariat, Ministry of Culture, Education, Research and Church, Nuuk, Greenland
P. B. Michaelsen
Danish Geodata Agency, Danish Ministry of the Environment, Copenhagen, Denmark
Related authors
Jonas Kvist Andersen, Rasmus Probst Meyer, Flora Salome Huiban, Mads Lykke Dømgaard, Romain Millan, and Anders Anker Bjørk
EGUsphere, https://doi.org/10.5194/egusphere-2024-3382, https://doi.org/10.5194/egusphere-2024-3382, 2024
Short summary
Short summary
Storstrømmen Glacier in northeast Greenland goes through cycles of sudden flow speed-ups (known as surges) followed by long quiet phases. Currently in its quiet phase, recent measurements suggest it may be nearing conditions for a new surge, possibly between 2027 and 2040. We also observed several lake drainages that caused brief increases in glacier flow but did not trigger a surge. Continued monitoring is essential to understand how these processes influence glacier behavior.
Mads Dømgaard, Kristian K. Kjeldsen, Flora Huiban, Jonathan L. Carrivick, Shfaqat A. Khan, and Anders A. Bjørk
The Cryosphere, 17, 1373–1387, https://doi.org/10.5194/tc-17-1373-2023, https://doi.org/10.5194/tc-17-1373-2023, 2023
Short summary
Short summary
Sudden releases of meltwater from glacier-dammed lakes can influence ice flow, cause flooding hazards and landscape changes. This study presents a record of 14 drainages from 2007–2021 from a lake in west Greenland. The time series reveals how the lake fluctuates between releasing large and small amounts of drainage water which is caused by a weakening of the damming glacier following the large events. We also find a shift in the water drainage route which increases the risk of flooding hazards.
Sophie Goliber, Taryn Black, Ginny Catania, James M. Lea, Helene Olsen, Daniel Cheng, Suzanne Bevan, Anders Bjørk, Charlie Bunce, Stephen Brough, J. Rachel Carr, Tom Cowton, Alex Gardner, Dominik Fahrner, Emily Hill, Ian Joughin, Niels J. Korsgaard, Adrian Luckman, Twila Moon, Tavi Murray, Andrew Sole, Michael Wood, and Enze Zhang
The Cryosphere, 16, 3215–3233, https://doi.org/10.5194/tc-16-3215-2022, https://doi.org/10.5194/tc-16-3215-2022, 2022
Short summary
Short summary
Terminus traces have been used to understand how Greenland's glaciers have changed over time; however, manual digitization is time-intensive, and a lack of coordination leads to duplication of efforts. We have compiled a dataset of over 39 000 terminus traces for 278 glaciers for scientific and machine learning applications. We also provide an overview of an updated version of the Google Earth Engine Digitization Tool (GEEDiT), which has been developed specifically for the Greenland Ice Sheet.
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.
Gregor Luetzenburg, Kristian Svennevig, Anders A. Bjørk, Marie Keiding, and Aart Kroon
Earth Syst. Sci. Data, 14, 3157–3165, https://doi.org/10.5194/essd-14-3157-2022, https://doi.org/10.5194/essd-14-3157-2022, 2022
Short summary
Short summary
We produced the first landslide inventory for Denmark. Over 3200 landslides were mapped using a high-resolution elevation model and orthophotos. We implemented an independent validation into our mapping and found an overall level of completeness of 87 %. The national inventory represents a range of landslide sizes covering all regions that were covered by glacial ice during the last glacial period. This inventory will be used for investigating landslide causes and for natural hazard mitigation.
William Colgan, Agnes Wansing, Kenneth Mankoff, Mareen Lösing, John Hopper, Keith Louden, Jörg Ebbing, Flemming G. Christiansen, Thomas Ingeman-Nielsen, Lillemor Claesson Liljedahl, Joseph A. MacGregor, Árni Hjartarson, Stefan Bernstein, Nanna B. Karlsson, Sven Fuchs, Juha Hartikainen, Johan Liakka, Robert S. Fausto, Dorthe Dahl-Jensen, Anders Bjørk, Jens-Ove Naslund, Finn Mørk, Yasmina Martos, Niels Balling, Thomas Funck, Kristian K. Kjeldsen, Dorthe Petersen, Ulrik Gregersen, Gregers Dam, Tove Nielsen, Shfaqat A. Khan, and Anja Løkkegaard
Earth Syst. Sci. Data, 14, 2209–2238, https://doi.org/10.5194/essd-14-2209-2022, https://doi.org/10.5194/essd-14-2209-2022, 2022
Short summary
Short summary
We assemble all available geothermal heat flow measurements collected in and around Greenland into a new database. We use this database of point measurements, in combination with other geophysical datasets, to model geothermal heat flow in and around Greenland. Our geothermal heat flow model is generally cooler than previous models of Greenland, especially in southern Greenland. It does not suggest any high geothermal heat flows resulting from Icelandic plume activity over 50 million years ago.
Svend Funder, Anita H. L. Sørensen, Nicolaj K. Larsen, Anders A. Bjørk, Jason P. Briner, Jesper Olsen, Anders Schomacker, Laura B. Levy, and Kurt H. Kjær
Clim. Past, 17, 587–601, https://doi.org/10.5194/cp-17-587-2021, https://doi.org/10.5194/cp-17-587-2021, 2021
Short summary
Short summary
Cosmogenic 10Be exposure dates from outlying islets along 300 km of the SW Greenland coast indicate that, although affected by inherited 10Be, the ice margin here was retreating during the Younger Dryas. These results seem to be corroborated by recent studies elsewhere in Greenland. The apparent mismatch between temperatures and ice margin behaviour may be explained by the advection of warm water to the ice margin on the shelf and by increased seasonality, both caused by a weakened AMOC.
Kristian Kjellerup Kjeldsen, Reimer Wilhelm Weinrebe, Jørgen Bendtsen, Anders Anker Bjørk, and Kurt Henrik Kjær
Earth Syst. Sci. Data, 9, 589–600, https://doi.org/10.5194/essd-9-589-2017, https://doi.org/10.5194/essd-9-589-2017, 2017
Short summary
Short summary
Here we present bathymetric and hydrographic measurements from two fjords in southeastern Greenland surveyed in 2014, leading to improved knowledge of the fjord morphology and an assessment of the variability in water masses in the fjords systems. Data were collected as part of a larger field campaign in which we targeted marine and terrestrial observations to assess the long-term behavior of the Greenland ice sheet and provide linkages to modern observations.
S. A. Khan, K. K. Kjeldsen, K. H. Kjær, S. Bevan, A. Luckman, A. Aschwanden, A. A. Bjørk, N. J. Korsgaard, J. E. Box, M. van den Broeke, T. M. van Dam, and A. Fitzner
The Cryosphere, 8, 1497–1507, https://doi.org/10.5194/tc-8-1497-2014, https://doi.org/10.5194/tc-8-1497-2014, 2014
Jonas Kvist Andersen, Rasmus Probst Meyer, Flora Salome Huiban, Mads Lykke Dømgaard, Romain Millan, and Anders Anker Bjørk
EGUsphere, https://doi.org/10.5194/egusphere-2024-3382, https://doi.org/10.5194/egusphere-2024-3382, 2024
Short summary
Short summary
Storstrømmen Glacier in northeast Greenland goes through cycles of sudden flow speed-ups (known as surges) followed by long quiet phases. Currently in its quiet phase, recent measurements suggest it may be nearing conditions for a new surge, possibly between 2027 and 2040. We also observed several lake drainages that caused brief increases in glacier flow but did not trigger a surge. Continued monitoring is essential to understand how these processes influence glacier behavior.
Mads Dømgaard, Kristian K. Kjeldsen, Flora Huiban, Jonathan L. Carrivick, Shfaqat A. Khan, and Anders A. Bjørk
The Cryosphere, 17, 1373–1387, https://doi.org/10.5194/tc-17-1373-2023, https://doi.org/10.5194/tc-17-1373-2023, 2023
Short summary
Short summary
Sudden releases of meltwater from glacier-dammed lakes can influence ice flow, cause flooding hazards and landscape changes. This study presents a record of 14 drainages from 2007–2021 from a lake in west Greenland. The time series reveals how the lake fluctuates between releasing large and small amounts of drainage water which is caused by a weakening of the damming glacier following the large events. We also find a shift in the water drainage route which increases the risk of flooding hazards.
Sophie Goliber, Taryn Black, Ginny Catania, James M. Lea, Helene Olsen, Daniel Cheng, Suzanne Bevan, Anders Bjørk, Charlie Bunce, Stephen Brough, J. Rachel Carr, Tom Cowton, Alex Gardner, Dominik Fahrner, Emily Hill, Ian Joughin, Niels J. Korsgaard, Adrian Luckman, Twila Moon, Tavi Murray, Andrew Sole, Michael Wood, and Enze Zhang
The Cryosphere, 16, 3215–3233, https://doi.org/10.5194/tc-16-3215-2022, https://doi.org/10.5194/tc-16-3215-2022, 2022
Short summary
Short summary
Terminus traces have been used to understand how Greenland's glaciers have changed over time; however, manual digitization is time-intensive, and a lack of coordination leads to duplication of efforts. We have compiled a dataset of over 39 000 terminus traces for 278 glaciers for scientific and machine learning applications. We also provide an overview of an updated version of the Google Earth Engine Digitization Tool (GEEDiT), which has been developed specifically for the Greenland Ice Sheet.
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.
Gregor Luetzenburg, Kristian Svennevig, Anders A. Bjørk, Marie Keiding, and Aart Kroon
Earth Syst. Sci. Data, 14, 3157–3165, https://doi.org/10.5194/essd-14-3157-2022, https://doi.org/10.5194/essd-14-3157-2022, 2022
Short summary
Short summary
We produced the first landslide inventory for Denmark. Over 3200 landslides were mapped using a high-resolution elevation model and orthophotos. We implemented an independent validation into our mapping and found an overall level of completeness of 87 %. The national inventory represents a range of landslide sizes covering all regions that were covered by glacial ice during the last glacial period. This inventory will be used for investigating landslide causes and for natural hazard mitigation.
William Colgan, Agnes Wansing, Kenneth Mankoff, Mareen Lösing, John Hopper, Keith Louden, Jörg Ebbing, Flemming G. Christiansen, Thomas Ingeman-Nielsen, Lillemor Claesson Liljedahl, Joseph A. MacGregor, Árni Hjartarson, Stefan Bernstein, Nanna B. Karlsson, Sven Fuchs, Juha Hartikainen, Johan Liakka, Robert S. Fausto, Dorthe Dahl-Jensen, Anders Bjørk, Jens-Ove Naslund, Finn Mørk, Yasmina Martos, Niels Balling, Thomas Funck, Kristian K. Kjeldsen, Dorthe Petersen, Ulrik Gregersen, Gregers Dam, Tove Nielsen, Shfaqat A. Khan, and Anja Løkkegaard
Earth Syst. Sci. Data, 14, 2209–2238, https://doi.org/10.5194/essd-14-2209-2022, https://doi.org/10.5194/essd-14-2209-2022, 2022
Short summary
Short summary
We assemble all available geothermal heat flow measurements collected in and around Greenland into a new database. We use this database of point measurements, in combination with other geophysical datasets, to model geothermal heat flow in and around Greenland. Our geothermal heat flow model is generally cooler than previous models of Greenland, especially in southern Greenland. It does not suggest any high geothermal heat flows resulting from Icelandic plume activity over 50 million years ago.
Svend Funder, Anita H. L. Sørensen, Nicolaj K. Larsen, Anders A. Bjørk, Jason P. Briner, Jesper Olsen, Anders Schomacker, Laura B. Levy, and Kurt H. Kjær
Clim. Past, 17, 587–601, https://doi.org/10.5194/cp-17-587-2021, https://doi.org/10.5194/cp-17-587-2021, 2021
Short summary
Short summary
Cosmogenic 10Be exposure dates from outlying islets along 300 km of the SW Greenland coast indicate that, although affected by inherited 10Be, the ice margin here was retreating during the Younger Dryas. These results seem to be corroborated by recent studies elsewhere in Greenland. The apparent mismatch between temperatures and ice margin behaviour may be explained by the advection of warm water to the ice margin on the shelf and by increased seasonality, both caused by a weakened AMOC.
Kristian Kjellerup Kjeldsen, Reimer Wilhelm Weinrebe, Jørgen Bendtsen, Anders Anker Bjørk, and Kurt Henrik Kjær
Earth Syst. Sci. Data, 9, 589–600, https://doi.org/10.5194/essd-9-589-2017, https://doi.org/10.5194/essd-9-589-2017, 2017
Short summary
Short summary
Here we present bathymetric and hydrographic measurements from two fjords in southeastern Greenland surveyed in 2014, leading to improved knowledge of the fjord morphology and an assessment of the variability in water masses in the fjords systems. Data were collected as part of a larger field campaign in which we targeted marine and terrestrial observations to assess the long-term behavior of the Greenland ice sheet and provide linkages to modern observations.
S. A. Khan, K. K. Kjeldsen, K. H. Kjær, S. Bevan, A. Luckman, A. Aschwanden, A. A. Bjørk, N. J. Korsgaard, J. E. Box, M. van den Broeke, T. M. van Dam, and A. Fitzner
The Cryosphere, 8, 1497–1507, https://doi.org/10.5194/tc-8-1497-2014, https://doi.org/10.5194/tc-8-1497-2014, 2014
Related subject area
Greenland
Impacts of differing melt regimes on satellite radar waveforms and elevation retrievals
The future of Upernavik Isstrøm through the ISMIP6 framework: sensitivity analysis and Bayesian calibration of ensemble prediction
Firn seismic anisotropy in the Northeast Greenland Ice Stream from ambient-noise surface waves
First results of the polar regional climate model RACMO2.4
Post-depositional modification on seasonal-to-interannual timescales alters the deuterium-excess signals in summer snow layers in Greenland
Seasonal snow cover indicators in coastal Greenland from in-situ observations, a climate model and reanalysis
Calving front monitoring at a subseasonal resolution: a deep learning application for Greenland glaciers
Projections of Precipitation and Temperatures in Greenland and the Impact of Spatially Uniform Anomalies on the Evolution of the Ice Sheet
Ice speed of a Greenlandic tidewater glacier modulated by tide, melt, and rain
Mapping the vertical heterogeneity of Greenland's firn from 2011–2019 using airborne radar and laser altimetry
Modelling present and future rock wall permafrost distribution in the Sisimiut mountain area, West Greenland
Subglacial valleys preserved in the highlands of south and east Greenland record restricted ice extent during past warmer climates
Coupling MAR (Modèle Atmosphérique Régional) with PISM (Parallel Ice Sheet Model) mitigates the positive melt–elevation feedback
Cloud- and ice-albedo feedbacks drive greater Greenland Ice Sheet sensitivity to warming in CMIP6 than in CMIP5
Evaluating different geothermal heat-flow maps as basal boundary conditions during spin-up of the Greenland ice sheet
Seasonal evolution of the supraglacial drainage network at Humboldt Glacier, northern Greenland, between 2016 and 2020
Choice of observation type affects Bayesian calibration of Greenland Ice Sheet model simulations
A topographically-controlled tipping point for complete Greenland ice-sheet melt
Effects of extreme melt events on ice flow and sea level rise of the Greenland Ice Sheet
Precursor of disintegration of Greenland's largest floating ice tongue
An evaluation of a physics-based firn model and a semi-empirical firn model across the Greenland Ice Sheet (1980–2020)
Subglacial lake activity beneath the ablation zone of the Greenland Ice Sheet
Exploring the role of snow metamorphism on the isotopic composition of the surface snow at EastGRIP
The control of short-term ice mélange weakening episodes on calving activity at major Greenland outlet glaciers
Weekly to monthly terminus variability of Greenland's marine-terminating outlet glaciers
The contribution of Humboldt Glacier, northern Greenland, to sea-level rise through 2100 constrained by recent observations of speedup and retreat
Observed mechanism for sustained glacier retreat and acceleration in response to ocean warming around Greenland
Assessing bare-ice albedo simulated by MAR over the Greenland ice sheet (2000–2021) and implications for meltwater production estimates
Drill-site selection for cosmogenic-nuclide exposure dating of the bed of the Greenland Ice Sheet
A new Level 4 multi-sensor ice surface temperature product for the Greenland Ice Sheet
High-resolution imaging of supraglacial hydrological features on the Greenland Ice Sheet with NASA's Airborne Topographic Mapper (ATM) instrument suite
The impact of climate oscillations on the surface energy budget over the Greenland Ice Sheet in a changing climate
GBaTSv2: a revised synthesis of the likely basal thermal state of the Greenland Ice Sheet
Unravelling the long-term, locally heterogenous response of Greenland glaciers observed in archival photography
Simulating the Holocene deglaciation across a marine-terminating portion of southwestern Greenland in response to marine and atmospheric forcings
Comparison of ice dynamics using full-Stokes and Blatter–Pattyn approximation: application to the Northeast Greenland Ice Stream
Melt probabilities and surface temperature trends on the Greenland ice sheet using a Gaussian mixture model
Modelling the effect of submarine iceberg melting on glacier-adjacent water properties
Multi-decadal retreat of marine-terminating outlet glaciers in northwest and central-west Greenland
Relating snowfall observations to Greenland ice sheet mass changes: an atmospheric circulation perspective
Sources of uncertainty in Greenland surface mass balance in the 21st century
Proper orthogonal decomposition of ice velocity identifies drivers of flow variability at Sermeq Kujalleq (Jakobshavn Isbræ)
Brief communication: A roadmap towards credible projections of ice sheet contribution to sea level
Automated detection and analysis of surface calving waves with a terrestrial radar interferometer at the front of Eqip Sermia, Greenland
Generation and fate of basal meltwater during winter, western Greenland Ice Sheet
Local-scale deposition of surface snow on the Greenland ice sheet
Modeling the Greenland englacial stratigraphy
Upstream flow effects revealed in the EastGRIP ice core using Monte Carlo inversion of a two-dimensional ice-flow model
Indication of high basal melting at the EastGRIP drill site on the Northeast Greenland Ice Stream
Brief communication: Reduction in the future Greenland ice sheet surface melt with the help of solar geoengineering
Alexander C. Ronan, Robert L. Hawley, and Jonathan W. Chipman
The Cryosphere, 18, 5673–5683, https://doi.org/10.5194/tc-18-5673-2024, https://doi.org/10.5194/tc-18-5673-2024, 2024
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We generate a 2010–2021 time series of CryoSat-2 waveform shape metrics on the Greenland Ice Sheet, and we compare it to CryoSat-2 elevation data to investigate the reliability of two algorithms used to derive elevations from the SIRAL radar altimeter. Retracked elevations are found to depend on a waveform's leading-edge width in the dry-snow zone. The study indicates that retracking algorithms must consider significant climate events and snow conditions when assessing elevation change.
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
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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.
Emma Pearce, Dimitri Zigone, Coen Hofstede, Andreas Fichtner, Joachim Rimpot, Sune Olander Rasmussen, Johannes Freitag, and Olaf Eisen
The Cryosphere, 18, 4917–4932, https://doi.org/10.5194/tc-18-4917-2024, https://doi.org/10.5194/tc-18-4917-2024, 2024
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Our study near EastGRIP camp in Greenland shows varying firn properties by direction (crucial for studying ice stream stability, structure, surface mass balance, and past climate conditions). We used dispersion curve analysis of Love and Rayleigh waves to show firn is nonuniform along and across the flow of an ice stream due to wind patterns, seasonal variability, and the proximity to the edge of the ice stream. This method better informs firn structure, advancing ice stream understanding.
Christiaan T. van Dalum, Willem Jan van de Berg, Srinidhi N. Gadde, Maurice van Tiggelen, Tijmen van der Drift, Erik van Meijgaard, Lambertus H. van Ulft, and Michiel R. van den Broeke
The Cryosphere, 18, 4065–4088, https://doi.org/10.5194/tc-18-4065-2024, https://doi.org/10.5194/tc-18-4065-2024, 2024
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We present a new version of the polar Regional Atmospheric Climate Model (RACMO), version 2.4p1, and show first results for Greenland, Antarctica and the Arctic. We provide an overview of all changes and investigate the impact that they have on the climate of polar regions. By comparing the results with observations and the output from the previous model version, we show that the model performs well regarding the surface mass balance of the ice sheets and near-surface climate.
Michael S. Town, Hans Christian Steen-Larsen, Sonja Wahl, Anne-Katrine Faber, Melanie Behrens, Tyler R. Jones, and Arny Sveinbjornsdottir
The Cryosphere, 18, 3653–3683, https://doi.org/10.5194/tc-18-3653-2024, https://doi.org/10.5194/tc-18-3653-2024, 2024
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A polar snow isotope dataset from northeast Greenland shows that snow changes isotopically after deposition. Summer snow sometimes enriches in oxygen-18, making it seem warmer than it actually was when the snow fell. Deuterium excess sometimes changes after deposition, making the snow seem to come from warmer, closer, or more humid places. After a year of aging, deuterium excess of summer snow layers always increases. Reinterpretation of deuterium excess used in climate models is necessary.
Jorrit van der Schot, Jakob Abermann, Tiago Silva, Kerstin Rasmussen, Michael Winkler, Kirsty Langley, and Wolfgang Schöner
EGUsphere, https://doi.org/10.5194/egusphere-2024-1999, https://doi.org/10.5194/egusphere-2024-1999, 2024
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We present snow data from nine locations in coastal Greenland. We show that a reanalysis product (CARRA) simulates seasonal snow characteristics better than a regional climate model (RACMO). CARRA output matches particularly well with our reference dataset when we look at the maximum snow water equivalent and the snow cover end date. We show that seasonal snow in coastal Greenland has large spatial and temporal variability and find little evidence of trends in snow cover characteristics.
Erik Loebel, Mirko Scheinert, Martin Horwath, Angelika Humbert, Julia Sohn, Konrad Heidler, Charlotte Liebezeit, and Xiao Xiang Zhu
The Cryosphere, 18, 3315–3332, https://doi.org/10.5194/tc-18-3315-2024, https://doi.org/10.5194/tc-18-3315-2024, 2024
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Comprehensive datasets of calving-front changes are essential for studying and modeling outlet glaciers. Current records are limited in temporal resolution due to manual delineation. We use deep learning to automatically delineate calving fronts for 23 glaciers in Greenland. Resulting time series resolve long-term, seasonal, and subseasonal patterns. We discuss the implications of our results and provide the cryosphere community with a data product and an implementation of our processing system.
Nils Bochow, Anna Poltronieri, and Niklas Boers
EGUsphere, https://doi.org/10.5194/egusphere-2024-1597, https://doi.org/10.5194/egusphere-2024-1597, 2024
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Using the latest climate models, we update the understanding of how the Greenland ice sheet responds to climate changes. We found that precipitation and temperature changes in Greenland vary across different regions. Our findings suggest that using uniform estimates for temperature and precipitation for modelling the response of the ice sheet can overestimate ice loss in Greenland. Therefore, this study highlights the need for spatially resolved data in predicting the ice sheet's future.
Shin Sugiyama, Shun Tsutaki, Daiki Sakakibara, Izumi Asaji, Ken Kondo, Yefan Wang, Evgeny Podolskiy, Guillaume Jouvet, and Martin Funk
EGUsphere, https://doi.org/10.5194/egusphere-2024-1476, https://doi.org/10.5194/egusphere-2024-1476, 2024
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We report flow speed variations near the front of a tidewater glacier in Greenland. Ice flow near the glacier front is crucial for the mass loss of the Greenland ice sheet, but in-situ data are hard to obtain. Our unique in-situ GPS data revealed fine details of short-term speed variations associated with melting, ocean tides, and rain. The results are important for understanding the response of tidewater glaciers to changing environments, such as warming, more frequent rain, and ice thinning.
Anja Rutishauser, Kirk M. Scanlan, Baptiste Vandecrux, Nanna B. Karlsson, Nicolas Jullien, Andreas P. Ahlstrøm, Robert S. Fausto, and Penelope How
The Cryosphere, 18, 2455–2472, https://doi.org/10.5194/tc-18-2455-2024, https://doi.org/10.5194/tc-18-2455-2024, 2024
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The Greenland Ice Sheet interior is covered by a layer of firn, which is important for surface meltwater runoff and contributions to global sea-level rise. Here, we combine airborne radar sounding and laser altimetry measurements to delineate vertically homogeneous and heterogeneous firn. Our results reveal changes in firn between 2011–2019, aligning well with known climatic events. This approach can be used to outline firn areas primed for significantly changing future meltwater runoff.
Marco Marcer, Pierre-Allain Duvillard, Soňa Tomaškovičová, Steffen Ringsø Nielsen, André Revil, and Thomas Ingeman-Nielsen
The Cryosphere, 18, 1753–1771, https://doi.org/10.5194/tc-18-1753-2024, https://doi.org/10.5194/tc-18-1753-2024, 2024
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This study models present and future rock wall temperatures in the mountains near Sisimiut, creating knowledge on mountain permafrost in Greenland for the first time. Bedrock is mostly frozen but also has temperatures near 0 oC, making it very sensitive to climate changes. Future climatic scenarios indicate a reduction in frozen rock wall areas. Since mountain permafrost thaw is linked to an increase in landslides, these results call for more efforts addressing mountain permafrost in Greenland.
Guy J. G. Paxman, Stewart S. R. Jamieson, Aisling M. Dolan, and Michael J. Bentley
The Cryosphere, 18, 1467–1493, https://doi.org/10.5194/tc-18-1467-2024, https://doi.org/10.5194/tc-18-1467-2024, 2024
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This study uses airborne radar data and satellite imagery to map mountainous topography hidden beneath the Greenland Ice Sheet. We find that the landscape records the former extent and configuration of ice masses that were restricted to areas of high topography. Computer models of ice flow indicate that valley glaciers eroded this landscape millions of years ago when local air temperatures were at least 4 °C higher than today and Greenland’s ice volume was < 10 % of that of the modern ice sheet.
Alison Delhasse, Johanna Beckmann, Christoph Kittel, and Xavier Fettweis
The Cryosphere, 18, 633–651, https://doi.org/10.5194/tc-18-633-2024, https://doi.org/10.5194/tc-18-633-2024, 2024
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Aiming to study the long-term influence of an extremely warm climate in the Greenland Ice Sheet contribution to sea level rise, a new regional atmosphere–ice sheet model setup was established. The coupling, explicitly considering the melt–elevation feedback, is compared to an offline method to consider this feedback. We highlight mitigation of the feedback due to local changes in atmospheric circulation with changes in surface topography, making the offline correction invalid on the margins.
Idunn Aamnes Mostue, Stefan Hofer, Trude Storelvmo, and Xavier Fettweis
The Cryosphere, 18, 475–488, https://doi.org/10.5194/tc-18-475-2024, https://doi.org/10.5194/tc-18-475-2024, 2024
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The latest generation of climate models (Coupled Model Intercomparison Project Phase 6 – CMIP6) warm more over Greenland and the Arctic and thus also project a larger mass loss from the Greenland Ice Sheet (GrIS) compared to the previous generation of climate models (CMIP5). Our work suggests for the first time that part of the greater mass loss in CMIP6 over the GrIS is driven by a difference in the surface mass balance sensitivity from a change in cloud representation in the CMIP6 models.
Tong Zhang, William Colgan, Agnes Wansing, Anja Løkkegaard, Gunter Leguy, William H. Lipscomb, and Cunde Xiao
The Cryosphere, 18, 387–402, https://doi.org/10.5194/tc-18-387-2024, https://doi.org/10.5194/tc-18-387-2024, 2024
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The geothermal heat flux determines how much heat enters from beneath the ice sheet, and thus impacts the temperature and the flow of the ice sheet. In this study we investigate how much geothermal heat flux impacts the initialization of the Greenland ice sheet. We use the Community Ice Sheet Model with two different initialization methods. We find a non-trivial influence of the choice of heat flow boundary conditions on the ice sheet initializations for further designs of ice sheet modeling.
Lauren D. Rawlins, David M. Rippin, Andrew J. Sole, Stephen J. Livingstone, and Kang Yang
The Cryosphere, 17, 4729–4750, https://doi.org/10.5194/tc-17-4729-2023, https://doi.org/10.5194/tc-17-4729-2023, 2023
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We map and quantify surface rivers and lakes at Humboldt Glacier to examine seasonal evolution and provide new insights of network configuration and behaviour. A widespread supraglacial drainage network exists, expanding up the glacier as seasonal runoff increases. Large interannual variability affects the areal extent of this network, controlled by high- vs. low-melt years, with late summer network persistence likely preconditioning the surface for earlier drainage activity the following year.
Denis Felikson, Sophie Nowicki, Isabel Nias, Beata Csatho, Anton Schenk, Michael J. Croteau, and Bryant Loomis
The Cryosphere, 17, 4661–4673, https://doi.org/10.5194/tc-17-4661-2023, https://doi.org/10.5194/tc-17-4661-2023, 2023
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We narrow the spread in model simulations of the Greenland Ice Sheet using velocity change, dynamic thickness change, and mass change observations. We find that the type of observation chosen can lead to significantly different calibrated probability distributions. Further work is required to understand how to best calibrate ensembles of ice sheet simulations because this will improve probability distributions of projected sea-level rise, which is crucial for coastal planning and adaptation.
Michele Petrini, Meike Scherrenberg, Laura Muntjewerf, Miren Vizcaino, Raymond Sellevold, Gunter Leguy, William Lipscomb, and Heiko Goelzer
The Cryosphere Discuss., https://doi.org/10.5194/tc-2023-154, https://doi.org/10.5194/tc-2023-154, 2023
Revised manuscript accepted for TC
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In this study, we investigate with a numerical model the stability of the Greenland ice-sheet under prolonged sustained warming and ice melt. We show that there is a threshold beyond which the ice-sheet will lose more than 80 % of its mass over tens of thousand of years. The point of no return is reached when the ice-sheet disconnects from a region of high topography in western Greenland. This threshold is determined by the interaction of surface and solid-Earth processes.
Johanna Beckmann and Ricarda Winkelmann
The Cryosphere, 17, 3083–3099, https://doi.org/10.5194/tc-17-3083-2023, https://doi.org/10.5194/tc-17-3083-2023, 2023
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Over the past decade, Greenland has experienced several extreme melt events.
With progressing climate change, such extreme melt events can be expected to occur more frequently and potentially become more severe and persistent.
Strong melt events may considerably contribute to Greenland's mass loss, which in turn strongly determines future sea level rise. How important these extreme melt events could be in the future is assessed in this study for the first time.
Angelika Humbert, Veit Helm, Niklas Neckel, Ole Zeising, Martin Rückamp, Shfaqat Abbas Khan, Erik Loebel, Jörg Brauchle, Karsten Stebner, Dietmar Gross, Rabea Sondershaus, and Ralf Müller
The Cryosphere, 17, 2851–2870, https://doi.org/10.5194/tc-17-2851-2023, https://doi.org/10.5194/tc-17-2851-2023, 2023
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The largest floating glacier mass in Greenland, the 79° N Glacier, is showing signs of instability. We investigate how crack formation at the glacier's calving front has changed over the last decades by using satellite imagery and airborne data. The calving front is about to lose contact to stabilizing ice islands. Simulations show that the glacier will accelerate as a result of this, leading to an increase in ice discharge of more than 5.1 % if its calving front retreats by 46 %.
Megan Thompson-Munson, Nander Wever, C. Max Stevens, Jan T. M. Lenaerts, and Brooke Medley
The Cryosphere, 17, 2185–2209, https://doi.org/10.5194/tc-17-2185-2023, https://doi.org/10.5194/tc-17-2185-2023, 2023
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To better understand the Greenland Ice Sheet’s firn layer and its ability to buffer sea level rise by storing meltwater, we analyze firn density observations and output from two firn models. We find that both models, one physics-based and one semi-empirical, simulate realistic density and firn air content when compared to observations. The models differ in their representation of firn air content, highlighting the uncertainty in physical processes and the paucity of deep-firn measurements.
Yubin Fan, Chang-Qing Ke, Xiaoyi Shen, Yao Xiao, Stephen J. Livingstone, and Andrew J. Sole
The Cryosphere, 17, 1775–1786, https://doi.org/10.5194/tc-17-1775-2023, https://doi.org/10.5194/tc-17-1775-2023, 2023
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We used the new-generation ICESat-2 altimeter to detect and monitor active subglacial lakes in unprecedented spatiotemporal detail. We created a new inventory of 18 active subglacial lakes as well as their elevation and volume changes during 2019–2020, which provides an improved understanding of how the Greenland subglacial water system operates and how these lakes are fed by water from the ice surface.
Romilly Harris Stuart, Anne-Katrine Faber, Sonja Wahl, Maria Hörhold, Sepp Kipfstuhl, Kristian Vasskog, Melanie Behrens, Alexandra M. Zuhr, and Hans Christian Steen-Larsen
The Cryosphere, 17, 1185–1204, https://doi.org/10.5194/tc-17-1185-2023, https://doi.org/10.5194/tc-17-1185-2023, 2023
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This empirical study uses continuous daily measurements from the Greenland Ice Sheet to document changes in surface snow properties. Consistent changes in snow isotopic composition are observed in the absence of deposition due to surface processes, indicating the isotopic signal of deposited precipitation is not always preserved. Our observations have potential implications for the interpretation of water isotopes in ice cores – historically assumed to reflect isotopic composition at deposition.
Adrien Wehrlé, Martin P. Lüthi, and Andreas Vieli
The Cryosphere, 17, 309–326, https://doi.org/10.5194/tc-17-309-2023, https://doi.org/10.5194/tc-17-309-2023, 2023
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We characterized short-lived episodes of ice mélange weakening (IMW) at the front of three major Greenland outlet glaciers. Through a continuous detection at the front of Kangerdlugssuaq Glacier during the June-to-September period from 2018 to 2021, we found that 87 % of the IMW episodes occurred prior to a large-scale calving event. Using a simple model for ice mélange motion, we further characterized the IMW process as self-sustained through the existence of an IMW–calving feedback.
Taryn E. Black and Ian Joughin
The Cryosphere, 17, 1–13, https://doi.org/10.5194/tc-17-1-2023, https://doi.org/10.5194/tc-17-1-2023, 2023
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The frontal positions of most ice-sheet-based glaciers in Greenland vary seasonally. On average, these glaciers begin retreating in May and begin advancing in October, and the difference between their most advanced and most retreated positions is 220 m. The timing may be related to the timing of melt on the ice sheet, and the seasonal length variation may be related to glacier speed. These seasonal variations can affect glacier behavior and, consequently, how much ice is lost from the ice sheet.
Trevor R. Hillebrand, Matthew J. Hoffman, Mauro Perego, Stephen F. Price, and Ian M. Howat
The Cryosphere, 16, 4679–4700, https://doi.org/10.5194/tc-16-4679-2022, https://doi.org/10.5194/tc-16-4679-2022, 2022
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We estimate that Humboldt Glacier, northern Greenland, will contribute 5.2–8.7 mm to global sea level in 2007–2100, using an ensemble of model simulations constrained by observations of glacier retreat and speedup. This is a significant fraction of the 40–140 mm from the whole Greenland Ice Sheet predicted by the recent ISMIP6 multi-model ensemble, suggesting that calibrating models against observed velocity changes could result in higher estimates of 21st century sea-level rise from Greenland.
Evan Carnahan, Ginny Catania, and Timothy C. Bartholomaus
The Cryosphere, 16, 4305–4317, https://doi.org/10.5194/tc-16-4305-2022, https://doi.org/10.5194/tc-16-4305-2022, 2022
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The Greenland Ice Sheet primarily loses mass through increased ice discharge. We find changes in discharge from outlet glaciers are initiated by ocean warming, which causes a change in the balance of forces resisting gravity and leads to acceleration. Vulnerable conditions for sustained retreat and acceleration are predetermined by the glacier-fjord geometry and exist around Greenland, suggesting increases in ice discharge may be sustained into the future despite a pause in ocean warming.
Raf M. Antwerpen, Marco Tedesco, Xavier Fettweis, Patrick Alexander, and Willem Jan van de Berg
The Cryosphere, 16, 4185–4199, https://doi.org/10.5194/tc-16-4185-2022, https://doi.org/10.5194/tc-16-4185-2022, 2022
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The ice on Greenland has been melting more rapidly over the last few years. Most of this melt comes from the exposure of ice when the overlying snow melts. This ice is darker than snow and absorbs more sunlight, leading to more melt. It remains challenging to accurately simulate the brightness of the ice. We show that the color of ice simulated by Modèle Atmosphérique Régional (MAR) is too bright. We then show that this means that MAR may underestimate how fast the Greenland ice is melting.
Jason P. Briner, Caleb K. Walcott, Joerg M. Schaefer, Nicolás E. Young, Joseph A. MacGregor, Kristin Poinar, Benjamin A. Keisling, Sridhar Anandakrishnan, Mary R. Albert, Tanner Kuhl, and Grant Boeckmann
The Cryosphere, 16, 3933–3948, https://doi.org/10.5194/tc-16-3933-2022, https://doi.org/10.5194/tc-16-3933-2022, 2022
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The 7.4 m of sea level equivalent stored as Greenland ice is getting smaller every year. The uncertain trajectory of ice loss could be better understood with knowledge of the ice sheet's response to past climate change. Within the bedrock below the present-day ice sheet is an archive of past ice-sheet history. We analyze all available data from Greenland to create maps showing where on the ice sheet scientists can drill, using currently available drills, to obtain sub-ice materials.
Ioanna Karagali, Magnus Barfod Suhr, Ruth Mottram, Pia Nielsen-Englyst, Gorm Dybkjær, Darren Ghent, and Jacob L. Høyer
The Cryosphere, 16, 3703–3721, https://doi.org/10.5194/tc-16-3703-2022, https://doi.org/10.5194/tc-16-3703-2022, 2022
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Ice surface temperature (IST) products were used to develop the first multi-sensor, gap-free Level 4 (L4) IST product of the Greenland Ice Sheet (GIS) for 2012, when a significant melt event occurred. For the melt season, mean IST was −15 to −1 °C, and almost the entire GIS experienced at least 1 to 5 melt days. Inclusion of the L4 IST to a surface mass budget (SMB) model improved simulated surface temperatures during the key onset of the melt season, where biases are typically large.
Michael Studinger, Serdar S. Manizade, Matthew A. Linkswiler, and James K. Yungel
The Cryosphere, 16, 3649–3668, https://doi.org/10.5194/tc-16-3649-2022, https://doi.org/10.5194/tc-16-3649-2022, 2022
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The footprint density and high-resolution imagery of airborne surveys reveal details in supraglacial hydrological features that are currently not obtainable from spaceborne data. The accuracy and resolution of airborne measurements complement spaceborne measurements, can support calibration and validation of spaceborne methods, and provide information necessary for process studies of the hydrological system on ice sheets that currently cannot be achieved from spaceborne observations alone.
Tiago Silva, Jakob Abermann, Brice Noël, Sonika Shahi, Willem Jan van de Berg, and Wolfgang Schöner
The Cryosphere, 16, 3375–3391, https://doi.org/10.5194/tc-16-3375-2022, https://doi.org/10.5194/tc-16-3375-2022, 2022
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To overcome internal climate variability, this study uses k-means clustering to combine NAO, GBI and IWV over the Greenland Ice Sheet (GrIS) and names the approach as the North Atlantic influence on Greenland (NAG). With the support of a polar-adapted RCM, spatio-temporal changes on SEB components within NAG phases are investigated. We report atmospheric warming and moistening across all NAG phases as well as large-scale and regional-scale contributions to GrIS mass loss and their interactions.
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.
Michael A. Cooper, Paulina Lewińska, William A. P. Smith, Edwin R. Hancock, Julian A. Dowdeswell, and David M. Rippin
The Cryosphere, 16, 2449–2470, https://doi.org/10.5194/tc-16-2449-2022, https://doi.org/10.5194/tc-16-2449-2022, 2022
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Here we use old photographs gathered several decades ago to expand the temporal record of glacier change in part of East Greenland. This is important because the longer the record of past glacier change, the better we are at predicting future glacier behaviour. Our work also shows that despite all these glaciers retreating, the rate at which they do this varies markedly. It is therefore important to consider outlet glaciers from Greenland individually to take account of this differing behaviour.
Joshua K. Cuzzone, Nicolás E. Young, Mathieu Morlighem, Jason P. Briner, and Nicole-Jeanne Schlegel
The Cryosphere, 16, 2355–2372, https://doi.org/10.5194/tc-16-2355-2022, https://doi.org/10.5194/tc-16-2355-2022, 2022
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We use an ice sheet model to determine what influenced the Greenland Ice Sheet to retreat across a portion of southwestern Greenland during the Holocene (about the last 12 000 years). Our simulations, constrained by observations from geologic markers, show that atmospheric warming and ice melt primarily caused the ice sheet to retreat rapidly across this domain. We find, however, that iceberg calving at the interface where the ice meets the ocean significantly influenced ice mass change.
Martin Rückamp, Thomas Kleiner, and Angelika Humbert
The Cryosphere, 16, 1675–1696, https://doi.org/10.5194/tc-16-1675-2022, https://doi.org/10.5194/tc-16-1675-2022, 2022
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We present a comparative modelling study between the full-Stokes (FS) and Blatter–Pattyn (BP) approximation applied to the Northeast Greenland Ice Stream. Both stress regimes are implemented in one single ice sheet code to eliminate numerical issues. The simulations unveil minor differences in the upper ice stream but become considerable at the grounding line of the 79° North Glacier. Model differences are stronger for a power-law friction than a linear friction law.
Daniel Clarkson, Emma Eastoe, and Amber Leeson
The Cryosphere, 16, 1597–1607, https://doi.org/10.5194/tc-16-1597-2022, https://doi.org/10.5194/tc-16-1597-2022, 2022
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The Greenland ice sheet has seen large amounts of melt in recent years, and accurately modelling temperatures is vital to understand how much of the ice sheet is melting. We estimate the probability of melt from ice surface temperature data to identify which areas of the ice sheet have experienced melt and estimate temperature quantiles. Our results suggest that for large areas of the ice sheet, melt has become more likely over the past 2 decades and high temperatures are also becoming warmer.
Benjamin Joseph Davison, Tom Cowton, Andrew Sole, Finlo Cottier, and Pete Nienow
The Cryosphere, 16, 1181–1196, https://doi.org/10.5194/tc-16-1181-2022, https://doi.org/10.5194/tc-16-1181-2022, 2022
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The ocean is an important driver of Greenland glacier retreat. Icebergs influence ocean temperature in the vicinity of glaciers, which will affect glacier retreat rates, but the effect of icebergs on water temperature is poorly understood. In this study, we use a model to show that icebergs cause large changes to water properties next to Greenland's glaciers, which could influence ocean-driven glacier retreat around Greenland.
Taryn E. Black and Ian Joughin
The Cryosphere, 16, 807–824, https://doi.org/10.5194/tc-16-807-2022, https://doi.org/10.5194/tc-16-807-2022, 2022
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We used satellite images to create a comprehensive record of annual glacier change in northwest Greenland from 1972 through 2021. We found that nearly all glaciers in our study area have retreated and glacier retreat accelerated from around 1996. Comparing these results with climate data, we found that glacier retreat is most sensitive to water runoff and moderately sensitive to ocean temperatures. These can affect glacier fronts in several ways, so no process clearly dominates glacier retreat.
Michael R. Gallagher, Matthew D. Shupe, Hélène Chepfer, and Tristan L'Ecuyer
The Cryosphere, 16, 435–450, https://doi.org/10.5194/tc-16-435-2022, https://doi.org/10.5194/tc-16-435-2022, 2022
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By using direct observations of snowfall and mass changes, the variability of daily snowfall mass input to the Greenland ice sheet is quantified for the first time. With new methods we conclude that cyclones west of Greenland in summer contribute the most snowfall, with 1.66 Gt per occurrence. These cyclones are contextualized in the broader Greenland climate, and snowfall is validated against mass changes to verify the results. Snowfall and mass change observations are shown to agree well.
Katharina M. Holube, Tobias Zolles, and Andreas Born
The Cryosphere, 16, 315–331, https://doi.org/10.5194/tc-16-315-2022, https://doi.org/10.5194/tc-16-315-2022, 2022
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We simulated the surface mass balance of the Greenland Ice Sheet in the 21st century by forcing a snow model with the output of many Earth system models and four greenhouse gas emission scenarios. We quantify the contribution to uncertainty in surface mass balance of these two factors and the choice of parameters of the snow model. The results show that the differences between Earth system models are the main source of uncertainty. This effect is localised mostly near the equilibrium line.
David W. Ashmore, Douglas W. F. Mair, Jonathan E. Higham, Stephen Brough, James M. Lea, and Isabel J. Nias
The Cryosphere, 16, 219–236, https://doi.org/10.5194/tc-16-219-2022, https://doi.org/10.5194/tc-16-219-2022, 2022
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In this paper we explore the use of a transferrable and flexible statistical technique to try and untangle the multiple influences on marine-terminating glacier dynamics, as measured from space. We decompose a satellite-derived ice velocity record into ranked sets of static maps and temporal coefficients. We present evidence that the approach can identify velocity variability mainly driven by changes in terminus position and velocity variation mainly driven by subglacial hydrological processes.
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.
Adrien Wehrlé, Martin P. Lüthi, Andrea Walter, Guillaume Jouvet, and Andreas Vieli
The Cryosphere, 15, 5659–5674, https://doi.org/10.5194/tc-15-5659-2021, https://doi.org/10.5194/tc-15-5659-2021, 2021
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We developed a novel automated method for the detection and the quantification of ocean waves generated by glacier calving. This method was applied to data recorded with a terrestrial radar interferometer at Eqip Sermia, Greenland. Results show a high calving activity at the glacier front sector ending in deep water linked with more frequent meltwater plumes. This suggests that rising subglacial meltwater plumes strongly affect glacier calving in deep water, but weakly in shallow water.
Joel Harper, Toby Meierbachtol, Neil Humphrey, Jun Saito, and Aidan Stansberry
The Cryosphere, 15, 5409–5421, https://doi.org/10.5194/tc-15-5409-2021, https://doi.org/10.5194/tc-15-5409-2021, 2021
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We use surface and borehole measurements to investigate the generation and fate of basal meltwater in the ablation zone of western Greenland. The rate of basal meltwater generation at borehole study sites increases by up to 20 % over the winter period. Accommodation of all basal meltwater by expansion of isolated subglacial cavities is implausible. Other sinks for water do not likely balance basal meltwater generation, implying water evacuation through a connected drainage system in winter.
Alexandra M. Zuhr, Thomas Münch, Hans Christian Steen-Larsen, Maria Hörhold, and Thomas Laepple
The Cryosphere, 15, 4873–4900, https://doi.org/10.5194/tc-15-4873-2021, https://doi.org/10.5194/tc-15-4873-2021, 2021
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Firn and ice cores are used to infer past temperatures. However, the imprint of the climatic signal in stable water isotopes is influenced by depositional modifications. We present and use a photogrammetry structure-from-motion approach and find variability in the amount, the timing, and the location of snowfall. Depositional modifications of the surface are observed, leading to mixing of snow from different snowfall events and spatial locations and thus creating noise in the proxy record.
Andreas Born and Alexander Robinson
The Cryosphere, 15, 4539–4556, https://doi.org/10.5194/tc-15-4539-2021, https://doi.org/10.5194/tc-15-4539-2021, 2021
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Ice penetrating radar reflections from the Greenland ice sheet are the best available record of past accumulation and how these layers have been deformed over time by the flow of ice. Direct simulations of this archive hold great promise for improving our models and for uncovering details of ice sheet dynamics that neither models nor data could achieve alone. We present the first three-dimensional ice sheet model that explicitly simulates individual layers of accumulation and how they deform.
Tamara Annina Gerber, Christine Schøtt Hvidberg, Sune Olander Rasmussen, Steven Franke, Giulia Sinnl, Aslak Grinsted, Daniela Jansen, and Dorthe Dahl-Jensen
The Cryosphere, 15, 3655–3679, https://doi.org/10.5194/tc-15-3655-2021, https://doi.org/10.5194/tc-15-3655-2021, 2021
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We simulate the ice flow in the onset region of the Northeast Greenland Ice Stream to determine the source area and past accumulation rates of ice found in the EastGRIP ice core. This information is required to correct for bias in ice-core records introduced by the upstream flow effects. Our results reveal that the increasing accumulation rate with increasing upstream distance is predominantly responsible for the constant annual layer thicknesses observed in the upper 900 m of the ice core.
Ole Zeising and Angelika Humbert
The Cryosphere, 15, 3119–3128, https://doi.org/10.5194/tc-15-3119-2021, https://doi.org/10.5194/tc-15-3119-2021, 2021
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Greenland’s largest ice stream – the Northeast Greenland Ice Stream (NEGIS) – extends far into the interior of the ice sheet. Basal meltwater acts as a lubricant for glaciers and sustains sliding. Hence, observations of basal melt rates are of high interest. We performed two time series of precise ground-based radar measurements in the upstream region of NEGIS and found high melt rates of 0.19 ± 0.04 m per year.
Xavier Fettweis, Stefan Hofer, Roland Séférian, Charles Amory, Alison Delhasse, Sébastien Doutreloup, Christoph Kittel, Charlotte Lang, Joris Van Bever, Florent Veillon, and Peter Irvine
The Cryosphere, 15, 3013–3019, https://doi.org/10.5194/tc-15-3013-2021, https://doi.org/10.5194/tc-15-3013-2021, 2021
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Without any reduction in our greenhouse gas emissions, the Greenland ice sheet surface mass loss can be brought in line with a medium-mitigation emissions scenario by reducing the solar downward flux at the top of the atmosphere by 1.5 %. In addition to reducing global warming, these solar geoengineering measures also dampen the well-known positive melt–albedo feedback over the ice sheet by 6 %. However, only stronger reductions in solar radiation could maintain a stable ice sheet in 2100.
Cited articles
Bevan, S. L., Luckman, A. J., and Murray, T.: Glacier dynamics over the last quarter of a century at Helheim, Kangerdlugssuaq and 14 other major Greenland outlet glaciers, The Cryosphere, 6, 923–937, https://doi.org/10.5194/tc-6-923-2012, 2012.
Fristrup, B.: Studies of four glaciers in Greenland, Danish J. Geogr., 59, 89–102, 1960.
Geodatastyrelsen: Den grønlandske Lods – Forklaringer til stednavne, Copenhagen, Denmark, 2013.
Hasholt, B.: Hydrology and transport of material in the Sermilik Area 1972, Danish J. Geogr., 75, 30–38, 1976.
Higgins, A. K.: Exploration history and place names of northern East Greenland, Geol. Surv. Denmark Greenl. Bull., 21, 368 pp., 2010.
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.
Jakobsson, M., Mayer, L., Coakley, B., Dowdeswell, J. A., Forbes, S., Fridman, B., Hodnesdal, H., Noormets, R., Pedersen, R., Rebesco, M., Schenke, H., Zarayskaya, Y., Accettella, D., Armstrong, A., Anderson, R., Bienhoff, P., Camerlenghi, A., Church, I., Edwards, M., Gardner, J., Hall, J., Hell, B., Hestvik, O., Kristoffersen, Y., Marcussen, C., Mohammad, R., Mosher, D., Nghiem, S., Pedrosa, M., Travaglini, P., and Weatherall, P.: The international bathymetric chart of the Arctic Ocean (IBCAO) version 3.0, Geophys. Res. Lett., 39, 1–6, 2012.
Joughin, I., Howat, I. M., Alley, R. B., Ekstrom, G., Fahnestock, M., Moon, T., Nettles, M., Truffer, M., and Tsai, V. C.: Ice-front variation and tidewater behavior on Helheim and Kangerdlugssuaq Glaciers, Greenland, J. Geophys. Res., 113, 1–11, https://doi.org/10.1029/2007JF000837, 2008.
Joughin, I., Smith, B. E., Shean, D. E., and Floricioiu, D.: Brief Communication: Further summer speedup of Jakobshavn Isbræ, The Cryosphere, 8, 209–214, https://doi.org/10.5194/tc-8-209-2014, 2014.
Khan, S., Kjeldsen, K. K., Kjær, K. H., Bevan, S. L., Luckman, A., Aschwanden, A., Bjørk, A. A., Korsgaard, N. J., Box, J. E., van den Broeke, M., van Dam, T. M., and Fitzner, A.: Glacier dynamics at Helheim and Kangerdlugssuaq glaciers, southeast Greenland, since the Little Ice Age, The Cryosphere, 8, 1497–1507, https://doi.org/10.5194/tc-8-1497-2014, 2014.
Kleivan, I.: Debate and linguistic usage in connection with double place-names in Greenland, in: Arctic Languages – An Awakening, edited by: Collins, D. R. F., UNESCO, Paris, 341–342, 1990.
Larsen, H. V.: Runoff studies from the Mitdluagkat Gletcher in SE-Greenland during the late summer 1958, Danish J. Geogr., 58, 54–65, 1959.
Laursen, D.: The Place Names of North Greenland, Meddelelser om Grønl., 180, 1–443, 1972.
Mernild, S. H., Knudsen, N. T., Lipscomb, W. H., Yde, J. C., Malmros, J. K., Hasholt, B., and Jakobsen, B. H.: Increasing mass loss from Greenland's Mittivakkat Gletscher, The Cryosphere, 5, 341–348, https://doi.org/10.5194/tc-5-341-2011, 2011.
Pfeffer, W. T., Arendt, A. A., Bliss, A., Bolch, T., Cogley, J. G., Gardner, A. S., Hagen, J.-O., Hock, R., Kaser, G., Kienholz, C., Miles, E. S., Moholdt, G., Mölg, N., Paul, F., Radić, V., Rastner, P., Raup, B., Rich, J., and Sharp, M. J.: The Randolph Glacier Inventory: a globally complete inventory of glaciers, J. Glaciol., 60, 537–552, https://doi.org/10.3189/2014JoG13J176, 2014.
Rasmussen, K.: Explorations in Southeastern Greenland: Preliminary Report of the Sixth and Seventh Thule Expeditions, Geogr. Rev., 23, 385–393, 1933.
Rastner, P., Bolch, T., Mölg, N., Machguth, H., Le Bris, R., and Paul, F.: The first complete inventory of the local glaciers and ice caps on Greenland, The Cryosphere, 6, 1483–1495, https://doi.org/10.5194/tc-6-1483-2012, 2012.
Rignot, E. and Mouginot, J.: Ice flow in Greenland for the International Polar Year 2008–2009, Geophys. Res. Lett., 39, L11501, https://doi.org/10.1029/2012GL051634, 2012.
Wager, L., Deer, W., Wager, H., and Manley, G.: The Kangerdlugssuak Region of East Greenland, Geogr. J., 90, 393–421, https://doi.org/10.2307/1787969, 1937.
Weidick, A.: Satellite Image Atlas of Glaciers of the World Greenland, US Geological Survey professional paper 1386-C, US. Geological Survey, Washington, US, 1995.
Short summary
During the last centuries hundreds of glaciers in Greenland have been mapped and named. Here we present the official database of all Greenlandic glacier names - consisting of 733 glacier names that have been approved by the Greenlandic authorities. This data set will help researchers working with Greenlandic glaciers in naming the glaciers properly in order to avoid future misunderstandings and will help the researcher who is looking for older glacier names found in the historic literature.
During the last centuries hundreds of glaciers in Greenland have been mapped and named. Here we...