Articles | Volume 13, issue 3
https://doi.org/10.5194/tc-13-911-2019
© Author(s) 2019. 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-13-911-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Large spatial variations in the flux balance along the front of a Greenland tidewater glacier
Department of Physics and Physical Oceanography, University of North Carolina Wilmington, NC 28403, USA
Fiamma Straneo
Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093, USA
Clark G. Richards
Bedford Institute of Oceanography, Fisheries and Oceans Canada, Dartmouth, NS B2Y 4A2, Canada
Donald A. Slater
Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA 92093, USA
Laura A. Stevens
Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, USA
Sarah B. Das
Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
Hanumant Singh
Department of Electrical & Computer Engineering, Northeastern University, Boston, MA 02115, USA
Related authors
Donald A. Slater and Till J. W. Wagner
EGUsphere, https://doi.org/10.5194/egusphere-2024-2927, https://doi.org/10.5194/egusphere-2024-2927, 2024
Short summary
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Calving is when icebergs break off glaciers and fall into the ocean. It is an important process determining how ice sheets will respond to change in climate, but it is currently poorly understood and hard to include in numerical models that are used for sea level projections. We revised an existing theory for how this process works, overcoming shortcomings of the existing theory and explaining observations showing that calving style depends on how thick the ice is.
Nicolas B. Sartore, Till J. W. Wagner, Matthew R. Siegfried, Nimish Pujara, and Lucas K. Zoet
EGUsphere, https://doi.org/10.5194/egusphere-2024-571, https://doi.org/10.5194/egusphere-2024-571, 2024
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We investigate how waves erode the front of Antarctica’s largest ice shelf, the Ross Ice Shelf, and how this erosion results in bending forces that can cause intermediate-scale calving (with icebergs of lengths ~100 m). We compare satellite observations to theoretical estimates of wave erosion and ice shelf bending to better understand the processes underlying this type of calving. We assess that these events may be responsible for roughly 25 % of the ice lost at the front of the Ross Ice Shelf.
Dominik Fahrner, Donald Slater, Aman KC, Claudia Cenedese, David A. Sutherland, Ellyn Enderlin, Femke de Jong, Kristian K. Kjeldsen, Michael Wood, Peter Nienow, Sophie Nowicki, and Till Wagner
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2023-411, https://doi.org/10.5194/essd-2023-411, 2023
Preprint withdrawn
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Marine-terminating glaciers can lose mass through frontal ablation, which comprises submarine and surface melting, and iceberg calving. We estimate frontal ablation for 49 marine-terminating glaciers in Greenland by combining existing, satellite derived data and calculating volume change near the glacier front over time. The dataset offers exciting opportunities to study the influence of climate forcings on marine-terminating glaciers in Greenland over multi-decadal timescales.
Benjamin Birner, Christo Buizert, Till J. W. Wagner, and Jeffrey P. Severinghaus
The Cryosphere, 12, 2021–2037, https://doi.org/10.5194/tc-12-2021-2018, https://doi.org/10.5194/tc-12-2021-2018, 2018
Short summary
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Ancient air enclosed in bubbles of the Antarctic ice sheet is a key source of information about the Earth's past climate. However, a range of physical processes in the snow layer atop an ice sheet may change the trapped air's chemical composition before it is occluded in the ice. We developed the first detailed 2-D computer simulation of these processes and found a new method to improve the reconstruction of past climate from air in ice cores bubbles.
Elizabeth Weidner, Grant Deane, Arnaud Le Boyer, Matthew H. Alford, Hari Vishnu, Mandar Chitre, M. Dale Stokes, Oskar Głowacki, Hayden Johnson, and Fiammetta Straneo
EGUsphere, https://doi.org/10.5194/egusphere-2024-3025, https://doi.org/10.5194/egusphere-2024-3025, 2024
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Tidewater glaciers play a central role in polar dynamics, but their study is limited by harsh and isolated conditions. Here, we introduce broadband echosounders as an tool for the study of high latitude fjords through the rapid collection of calibrated high resolution, near-synoptic observations. Using a data set collected in Hornsund fjord we illustrate the potential of broadband echosounders as a relatively low-cost, low-effort tool, well suited for field deployment in high-latitude fjords.
Donald A. Slater and Till J. W. Wagner
EGUsphere, https://doi.org/10.5194/egusphere-2024-2927, https://doi.org/10.5194/egusphere-2024-2927, 2024
Short summary
Short summary
Calving is when icebergs break off glaciers and fall into the ocean. It is an important process determining how ice sheets will respond to change in climate, but it is currently poorly understood and hard to include in numerical models that are used for sea level projections. We revised an existing theory for how this process works, overcoming shortcomings of the existing theory and explaining observations showing that calving style depends on how thick the ice is.
Hanwen Zhang, Richard F. Katz, and Laura A. Stevens
EGUsphere, https://doi.org/10.48550/arXiv.2311.01249, https://doi.org/10.48550/arXiv.2311.01249, 2024
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In Antarctica, supraglacial lakes are formed by melting near the grounding lines, where grounded ice sheets transition to floating ice shelves. We model the tidal flexure near the grounding lines and analyse its contribution to lake drainage through hydrofracturing. We show that tidal flexure and lake water pressure together control lake drainage in the Amery Ice Shelf, which indicates the importance of tidal stress to processes associated with hydrofracturing near the grounding lines.
Nicolas B. Sartore, Till J. W. Wagner, Matthew R. Siegfried, Nimish Pujara, and Lucas K. Zoet
EGUsphere, https://doi.org/10.5194/egusphere-2024-571, https://doi.org/10.5194/egusphere-2024-571, 2024
Short summary
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We investigate how waves erode the front of Antarctica’s largest ice shelf, the Ross Ice Shelf, and how this erosion results in bending forces that can cause intermediate-scale calving (with icebergs of lengths ~100 m). We compare satellite observations to theoretical estimates of wave erosion and ice shelf bending to better understand the processes underlying this type of calving. We assess that these events may be responsible for roughly 25 % of the ice lost at the front of the Ross Ice Shelf.
Alexander O. Hager, David A. Sutherland, and Donald A. Slater
The Cryosphere, 18, 911–932, https://doi.org/10.5194/tc-18-911-2024, https://doi.org/10.5194/tc-18-911-2024, 2024
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Warming ocean temperatures cause considerable ice loss from the Greenland Ice Sheet; however climate models are unable to resolve the complex ocean processes within fjords that influence near-glacier ocean temperatures. Here, we use a computer model to test the accuracy of assumptions that allow climate and ice sheet models to project near-glacier ocean temperatures, and thus glacier melt, into the future. We then develop new methods that improve accuracy by accounting for local ocean processes.
Dominik Fahrner, Donald Slater, Aman KC, Claudia Cenedese, David A. Sutherland, Ellyn Enderlin, Femke de Jong, Kristian K. Kjeldsen, Michael Wood, Peter Nienow, Sophie Nowicki, and Till Wagner
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2023-411, https://doi.org/10.5194/essd-2023-411, 2023
Preprint withdrawn
Short summary
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Marine-terminating glaciers can lose mass through frontal ablation, which comprises submarine and surface melting, and iceberg calving. We estimate frontal ablation for 49 marine-terminating glaciers in Greenland by combining existing, satellite derived data and calculating volume change near the glacier front over time. The dataset offers exciting opportunities to study the influence of climate forcings on marine-terminating glaciers in Greenland over multi-decadal timescales.
Hélène Seroussi, Vincent Verjans, Sophie Nowicki, Antony J. Payne, Heiko Goelzer, William H. Lipscomb, Ayako Abe-Ouchi, Cécile Agosta, Torsten Albrecht, Xylar Asay-Davis, Alice Barthel, Reinhard Calov, Richard Cullather, Christophe Dumas, Benjamin K. Galton-Fenzi, Rupert Gladstone, Nicholas R. Golledge, Jonathan M. Gregory, Ralf Greve, Tore Hattermann, Matthew J. Hoffman, Angelika Humbert, Philippe Huybrechts, Nicolas C. Jourdain, Thomas Kleiner, Eric Larour, Gunter R. Leguy, Daniel P. Lowry, Chistopher M. Little, Mathieu Morlighem, Frank Pattyn, Tyler Pelle, Stephen F. Price, Aurélien Quiquet, Ronja Reese, Nicole-Jeanne Schlegel, Andrew Shepherd, Erika Simon, Robin S. Smith, Fiammetta Straneo, Sainan Sun, Luke D. Trusel, Jonas Van Breedam, Peter Van Katwyk, Roderik S. W. van de Wal, Ricarda Winkelmann, Chen Zhao, Tong Zhang, and Thomas Zwinger
The Cryosphere, 17, 5197–5217, https://doi.org/10.5194/tc-17-5197-2023, https://doi.org/10.5194/tc-17-5197-2023, 2023
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Mass loss from Antarctica is a key contributor to sea level rise over the 21st century, and the associated uncertainty dominates sea level projections. We highlight here the Antarctic glaciers showing the largest changes and quantify the main sources of uncertainty in their future evolution using an ensemble of ice flow models. We show that on top of Pine Island and Thwaites glaciers, Totten and Moscow University glaciers show rapid changes and a strong sensitivity to warmer ocean conditions.
Michael J. Bentley, James A. Smith, Stewart S. R. Jamieson, Margaret R. Lindeman, Brice R. Rea, Angelika Humbert, Timothy P. Lane, Christopher M. Darvill, Jeremy M. Lloyd, Fiamma Straneo, Veit Helm, and David H. Roberts
The Cryosphere, 17, 1821–1837, https://doi.org/10.5194/tc-17-1821-2023, https://doi.org/10.5194/tc-17-1821-2023, 2023
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The Northeast Greenland Ice Stream is a major outlet of the Greenland Ice Sheet. Some of its outlet glaciers and ice shelves have been breaking up and retreating, with inflows of warm ocean water identified as the likely reason. Here we report direct measurements of warm ocean water in an unusual lake that is connected to the ocean beneath the ice shelf in front of the 79° N Glacier. This glacier has not yet shown much retreat, but the presence of warm water makes future retreat more likely.
Karina von Schuckmann, Audrey Minière, Flora Gues, Francisco José Cuesta-Valero, Gottfried Kirchengast, Susheel Adusumilli, Fiammetta Straneo, Michaël Ablain, Richard P. Allan, Paul M. Barker, Hugo Beltrami, Alejandro Blazquez, Tim Boyer, Lijing Cheng, John Church, Damien Desbruyeres, Han Dolman, Catia M. Domingues, Almudena García-García, Donata Giglio, John E. Gilson, Maximilian Gorfer, Leopold Haimberger, Maria Z. Hakuba, Stefan Hendricks, Shigeki Hosoda, Gregory C. Johnson, Rachel Killick, Brian King, Nicolas Kolodziejczyk, Anton Korosov, Gerhard Krinner, Mikael Kuusela, Felix W. Landerer, Moritz Langer, Thomas Lavergne, Isobel Lawrence, Yuehua Li, John Lyman, Florence Marti, Ben Marzeion, Michael Mayer, Andrew H. MacDougall, Trevor McDougall, Didier Paolo Monselesan, Jan Nitzbon, Inès Otosaka, Jian Peng, Sarah Purkey, Dean Roemmich, Kanako Sato, Katsunari Sato, Abhishek Savita, Axel Schweiger, Andrew Shepherd, Sonia I. Seneviratne, Leon Simons, Donald A. Slater, Thomas Slater, Andrea K. Steiner, Toshio Suga, Tanguy Szekely, Wim Thiery, Mary-Louise Timmermans, Inne Vanderkelen, Susan E. Wjiffels, Tonghua Wu, and Michael Zemp
Earth Syst. Sci. Data, 15, 1675–1709, https://doi.org/10.5194/essd-15-1675-2023, https://doi.org/10.5194/essd-15-1675-2023, 2023
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Earth's climate is out of energy balance, and this study quantifies how much heat has consequently accumulated over the past decades (ocean: 89 %, land: 6 %, cryosphere: 4 %, atmosphere: 1 %). Since 1971, this accumulated heat reached record values at an increasing pace. The Earth heat inventory provides a comprehensive view on the status and expectation of global warming, and we call for an implementation of this global climate indicator into the Paris Agreement’s Global Stocktake.
Karita Kajanto, Fiammetta Straneo, and Kerim Nisancioglu
The Cryosphere, 17, 371–390, https://doi.org/10.5194/tc-17-371-2023, https://doi.org/10.5194/tc-17-371-2023, 2023
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Many outlet glaciers in Greenland are connected to the ocean by narrow glacial fjords, where warm water melts the glacier from underneath. Ocean water is modified in these fjords through processes that are poorly understood, particularly iceberg melt. We use a model to show how iceberg melt cools down Ilulissat Icefjord and causes circulation to take place deeper in the fjord than if there were no icebergs. This causes the glacier to melt less and from a smaller area than without icebergs.
Alison F. Banwell, Rajashree Tri Datta, Rebecca L. Dell, Mahsa Moussavi, Ludovic Brucker, Ghislain Picard, Christopher A. Shuman, and Laura A. Stevens
The Cryosphere, 15, 909–925, https://doi.org/10.5194/tc-15-909-2021, https://doi.org/10.5194/tc-15-909-2021, 2021
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Ice shelves are thick floating layers of glacier ice extending from the glaciers on land that buttress much of the Antarctic Ice Sheet and help to protect it from losing ice to the ocean. However, the stability of ice shelves is vulnerable to meltwater lakes that form on their surfaces during the summer. This study focuses on the northern George VI Ice Shelf on the western side of the AP, which had an exceptionally long and extensive melt season in 2019/2020 compared to the previous 31 seasons.
Nicolas C. Jourdain, Xylar Asay-Davis, Tore Hattermann, Fiammetta Straneo, Hélène Seroussi, Christopher M. Little, and Sophie Nowicki
The Cryosphere, 14, 3111–3134, https://doi.org/10.5194/tc-14-3111-2020, https://doi.org/10.5194/tc-14-3111-2020, 2020
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To predict the future Antarctic contribution to sea level rise, we need to use ice sheet models. The Ice Sheet Model Intercomparison Project for AR6 (ISMIP6) builds an ensemble of ice sheet projections constrained by atmosphere and ocean projections from the 6th Coupled Model Intercomparison Project (CMIP6). In this work, we present and assess a method to derive ice shelf basal melting in ISMIP6 from the CMIP6 ocean outputs, and we give examples of projected melt rates.
Heiko Goelzer, Sophie Nowicki, Anthony Payne, Eric Larour, Helene Seroussi, William H. Lipscomb, Jonathan Gregory, Ayako Abe-Ouchi, Andrew Shepherd, Erika Simon, Cécile Agosta, Patrick Alexander, Andy Aschwanden, Alice Barthel, Reinhard Calov, Christopher Chambers, Youngmin Choi, Joshua Cuzzone, Christophe Dumas, Tamsin Edwards, Denis Felikson, Xavier Fettweis, Nicholas R. Golledge, Ralf Greve, Angelika Humbert, Philippe Huybrechts, Sebastien Le clec'h, Victoria Lee, Gunter Leguy, Chris Little, Daniel P. Lowry, Mathieu Morlighem, Isabel Nias, Aurelien Quiquet, Martin Rückamp, Nicole-Jeanne Schlegel, Donald A. Slater, Robin S. Smith, Fiamma Straneo, Lev Tarasov, Roderik van de Wal, and Michiel van den Broeke
The Cryosphere, 14, 3071–3096, https://doi.org/10.5194/tc-14-3071-2020, https://doi.org/10.5194/tc-14-3071-2020, 2020
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In this paper we use a large ensemble of Greenland ice sheet models forced by six different global climate models to project ice sheet changes and sea-level rise contributions over the 21st century.
The results for two different greenhouse gas concentration scenarios indicate that the Greenland ice sheet will continue to lose mass until 2100, with contributions to sea-level rise of 90 ± 50 mm and 32 ± 17 mm for the high (RCP8.5) and low (RCP2.6) scenario, respectively.
Hélène Seroussi, Sophie Nowicki, Antony J. Payne, Heiko Goelzer, William H. Lipscomb, Ayako Abe-Ouchi, Cécile Agosta, Torsten Albrecht, Xylar Asay-Davis, Alice Barthel, Reinhard Calov, Richard Cullather, Christophe Dumas, Benjamin K. Galton-Fenzi, Rupert Gladstone, Nicholas R. Golledge, Jonathan M. Gregory, Ralf Greve, Tore Hattermann, Matthew J. Hoffman, Angelika Humbert, Philippe Huybrechts, Nicolas C. Jourdain, Thomas Kleiner, Eric Larour, Gunter R. Leguy, Daniel P. Lowry, Chistopher M. Little, Mathieu Morlighem, Frank Pattyn, Tyler Pelle, Stephen F. Price, Aurélien Quiquet, Ronja Reese, Nicole-Jeanne Schlegel, Andrew Shepherd, Erika Simon, Robin S. Smith, Fiammetta Straneo, Sainan Sun, Luke D. Trusel, Jonas Van Breedam, Roderik S. W. van de Wal, Ricarda Winkelmann, Chen Zhao, Tong Zhang, and Thomas Zwinger
The Cryosphere, 14, 3033–3070, https://doi.org/10.5194/tc-14-3033-2020, https://doi.org/10.5194/tc-14-3033-2020, 2020
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The Antarctic ice sheet has been losing mass over at least the past 3 decades in response to changes in atmospheric and oceanic conditions. This study presents an ensemble of model simulations of the Antarctic evolution over the 2015–2100 period based on various ice sheet models, climate forcings and emission scenarios. Results suggest that the West Antarctic ice sheet will continue losing a large amount of ice, while the East Antarctic ice sheet could experience increased snow accumulation.
Karina von Schuckmann, Lijing Cheng, Matthew D. Palmer, James Hansen, Caterina Tassone, Valentin Aich, Susheel Adusumilli, Hugo Beltrami, Tim Boyer, Francisco José Cuesta-Valero, Damien Desbruyères, Catia Domingues, Almudena García-García, Pierre Gentine, John Gilson, Maximilian Gorfer, Leopold Haimberger, Masayoshi Ishii, Gregory C. Johnson, Rachel Killick, Brian A. King, Gottfried Kirchengast, Nicolas Kolodziejczyk, John Lyman, Ben Marzeion, Michael Mayer, Maeva Monier, Didier Paolo Monselesan, Sarah Purkey, Dean Roemmich, Axel Schweiger, Sonia I. Seneviratne, Andrew Shepherd, Donald A. Slater, Andrea K. Steiner, Fiammetta Straneo, Mary-Louise Timmermans, and Susan E. Wijffels
Earth Syst. Sci. Data, 12, 2013–2041, https://doi.org/10.5194/essd-12-2013-2020, https://doi.org/10.5194/essd-12-2013-2020, 2020
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Understanding how much and where the heat is distributed in the Earth system is fundamental to understanding how this affects warming oceans, atmosphere and land, rising temperatures and sea level, and loss of grounded and floating ice, which are fundamental concerns for society. This study is a Global Climate Observing System (GCOS) concerted international effort to obtain the Earth heat inventory over the period 1960–2018.
Christopher Gordon, Katja Fennel, Clark Richards, Lynn K. Shay, and Jodi K. Brewster
Biogeosciences, 17, 4119–4134, https://doi.org/10.5194/bg-17-4119-2020, https://doi.org/10.5194/bg-17-4119-2020, 2020
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We describe a method for correcting errors in oxygen optode measurements on autonomous platforms in the ocean. The errors result from the relatively slow response time of the sensor. The correction method includes an in situ determination of the effective response time and requires the time stamps of the individual measurements. It is highly relevant for the BGC-Argo program and also applicable to gliders. We also explore if diurnal changes in oxygen can be obtained from profiling floats.
Sophie Nowicki, Heiko Goelzer, Hélène Seroussi, Anthony J. Payne, William H. Lipscomb, Ayako Abe-Ouchi, Cécile Agosta, Patrick Alexander, Xylar S. Asay-Davis, Alice Barthel, Thomas J. Bracegirdle, Richard Cullather, Denis Felikson, Xavier Fettweis, Jonathan M. Gregory, Tore Hattermann, Nicolas C. Jourdain, Peter Kuipers Munneke, Eric Larour, Christopher M. Little, Mathieu Morlighem, Isabel Nias, Andrew Shepherd, Erika Simon, Donald Slater, Robin S. Smith, Fiammetta Straneo, Luke D. Trusel, Michiel R. van den Broeke, and Roderik van de Wal
The Cryosphere, 14, 2331–2368, https://doi.org/10.5194/tc-14-2331-2020, https://doi.org/10.5194/tc-14-2331-2020, 2020
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This paper describes the experimental protocol for ice sheet models taking part in the Ice Sheet Model Intercomparion Project for CMIP6 (ISMIP6) and presents an overview of the atmospheric and oceanic datasets to be used for the simulations. The ISMIP6 framework allows for exploring the uncertainty in 21st century sea level change from the Greenland and Antarctic ice sheets.
Eva De Andrés, Donald A. Slater, Fiamma Straneo, Jaime Otero, Sarah Das, and Francisco Navarro
The Cryosphere, 14, 1951–1969, https://doi.org/10.5194/tc-14-1951-2020, https://doi.org/10.5194/tc-14-1951-2020, 2020
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Buoyant plumes at tidewater glaciers result from localized subglacial discharges of surface melt. They promote glacier submarine melting and influence the delivery of nutrients to the fjord's surface waters. Combining plume theory with observations, we have found that increased fjord stratification, which is due to larger meltwater content, prevents the vertical growth of the plume and buffers submarine melting. We discuss the implications for nutrient fluxes, CO2 trapping and water export.
Donald A. Slater, Denis Felikson, Fiamma Straneo, Heiko Goelzer, Christopher M. Little, Mathieu Morlighem, Xavier Fettweis, and Sophie Nowicki
The Cryosphere, 14, 985–1008, https://doi.org/10.5194/tc-14-985-2020, https://doi.org/10.5194/tc-14-985-2020, 2020
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Changes in the ocean around Greenland play an important role in determining how much the ice sheet will contribute to global sea level over the coming century. However, capturing these links in models is very challenging. This paper presents a strategy enabling an ensemble of ice sheet models to feel the effect of the ocean for the first time and should therefore result in a significant improvement in projections of the Greenland ice sheet's contribution to future sea level change.
Samuel J. Cook, Poul Christoffersen, Joe Todd, Donald Slater, and Nolwenn Chauché
The Cryosphere, 14, 905–924, https://doi.org/10.5194/tc-14-905-2020, https://doi.org/10.5194/tc-14-905-2020, 2020
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This paper models how water flows beneath a large Greenlandic glacier and how the structure of the drainage system it flows in changes over time. We also look at how this affects melting driven by freshwater plumes at the glacier front, as well as the implications for glacier flow and sea-level rise. We find an active drainage system and plumes exist year round, contradicting previous assumptions and suggesting more melting may not slow the glacier down, unlike at other sites in Greenland.
Alice Barthel, Cécile Agosta, Christopher M. Little, Tore Hattermann, Nicolas C. Jourdain, Heiko Goelzer, Sophie Nowicki, Helene Seroussi, Fiammetta Straneo, and Thomas J. Bracegirdle
The Cryosphere, 14, 855–879, https://doi.org/10.5194/tc-14-855-2020, https://doi.org/10.5194/tc-14-855-2020, 2020
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We compare existing coupled climate models to select a total of six models to provide forcing to the Greenland and Antarctic ice sheet simulations of the Ice Sheet Model Intercomparison Project (ISMIP6). We select models based on (i) their representation of current climate near Antarctica and Greenland relative to observations and (ii) their ability to sample a diversity of projected atmosphere and ocean changes over the 21st century.
M. Jeffrey Mei, Ted Maksym, Blake Weissling, and Hanumant Singh
The Cryosphere, 13, 2915–2934, https://doi.org/10.5194/tc-13-2915-2019, https://doi.org/10.5194/tc-13-2915-2019, 2019
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Sea ice thickness is hard to measure directly, and current datasets are very limited to sporadically conducted drill lines. However, surface elevation is much easier to measure. Converting surface elevation to ice thickness requires making assumptions about snow depth and density, which leads to large errors (and may not generalize to new datasets). A deep learning method is presented that uses the surface morphology as a direct predictor of sea ice thickness, with testing errors of < 20 %.
Donald A. Slater, Fiamma Straneo, Denis Felikson, Christopher M. Little, Heiko Goelzer, Xavier Fettweis, and James Holte
The Cryosphere, 13, 2489–2509, https://doi.org/10.5194/tc-13-2489-2019, https://doi.org/10.5194/tc-13-2489-2019, 2019
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The ocean's influence on the retreat of Greenland's tidewater glaciers is a key factor determining future sea level. By considering observations of ~200 glaciers from 1960, we find a significant relationship between retreat and melting in the ocean. Projected forwards, this relationship estimates the future evolution of Greenland's tidewater glaciers and provides a practical and empirically validated way of representing ice–ocean interaction in large-scale models used to estimate sea level rise.
Philipp Anhaus, Lars H. Smedsrud, Marius Årthun, and Fiammetta Straneo
The Cryosphere Discuss., https://doi.org/10.5194/tc-2019-35, https://doi.org/10.5194/tc-2019-35, 2019
Revised manuscript not accepted
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Atlantic Water flows towards the Arctic and under floating glaciers on Greenland. Observations in a rift on the 79 North Glacier show presence of such water with temperature of 1 °C at 600 m. We simulate how this warm water melts the floating ice. Melt rates are largest where the glacier starts floating, are smaller where the water rises, and increase linearly with rising ocean temperature. Our results improve the understanding of ocean processes driving melting of floating glaciers.
Marilena Oltmanns, Fiammetta Straneo, and Marco Tedesco
The Cryosphere, 13, 815–825, https://doi.org/10.5194/tc-13-815-2019, https://doi.org/10.5194/tc-13-815-2019, 2019
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By combining reanalysis, weather station and satellite data, we show that increases in surface melt over Greenland are initiated by large-scale precipitation events year-round. Estimates from a regional climate model suggest that the initiated melting more than doubled between 1988 and 2012, amounting to ~28 % of the overall melt and revealing that, despite the involved mass gain, precipitation events are contributing to the ice sheet's decline.
Benjamin Birner, Christo Buizert, Till J. W. Wagner, and Jeffrey P. Severinghaus
The Cryosphere, 12, 2021–2037, https://doi.org/10.5194/tc-12-2021-2018, https://doi.org/10.5194/tc-12-2021-2018, 2018
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Ancient air enclosed in bubbles of the Antarctic ice sheet is a key source of information about the Earth's past climate. However, a range of physical processes in the snow layer atop an ice sheet may change the trapped air's chemical composition before it is occluded in the ice. We developed the first detailed 2-D computer simulation of these processes and found a new method to improve the reconstruction of past climate from air in ice cores bubbles.
Matthew Osman, Maria A. Zawadowicz, Sarah B. Das, and Daniel J. Cziczo
Atmos. Meas. Tech., 10, 4459–4477, https://doi.org/10.5194/amt-10-4459-2017, https://doi.org/10.5194/amt-10-4459-2017, 2017
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This study presents the first-time attempt at using time-of-flight single particle mass spectrometry (SPMS) as an emerging online technique for measuring insoluble particles in glacial snow and ice. Using samples from two Greenlandic ice cores, we show that SPMS can constrain the aerodynamic size, composition, and relative abundance of most particulate types on a per-particle basis, reducing the preparation time and resources required of conventional, filter-based particle retrieval methods.
Matthew Osman, Sarah B. Das, Olivier Marchal, and Matthew J. Evans
The Cryosphere, 11, 2439–2462, https://doi.org/10.5194/tc-11-2439-2017, https://doi.org/10.5194/tc-11-2439-2017, 2017
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We combine a synthesis of 22 ice core records and a model of soluble impurity transport to investigate the enigmatic, post-depositional migration of methanesulfonic acid in polar ice. Our findings suggest that migration may be universal across coastal regions of Greenland and Antarctica, though it is mitigated at sites with higher accumulation and (or) lower impurity content. Records exhibiting severe migration may still be useful for inferring decadal and lower-frequency climate variability.
Related subject area
Discipline: Glaciers | Subject: Ocean Interactions
Review article: How does glacier discharge affect marine biogeochemistry and primary production in the Arctic?
Spatiotemporal distributions of icebergs in a temperate fjord: Columbia Fjord, Alaska
Mark J. Hopwood, Dustin Carroll, Thorben Dunse, Andy Hodson, Johnna M. Holding, José L. Iriarte, Sofia Ribeiro, Eric P. Achterberg, Carolina Cantoni, Daniel F. Carlson, Melissa Chierici, Jennifer S. Clarke, Stefano Cozzi, Agneta Fransson, Thomas Juul-Pedersen, Mie H. S. Winding, and Lorenz Meire
The Cryosphere, 14, 1347–1383, https://doi.org/10.5194/tc-14-1347-2020, https://doi.org/10.5194/tc-14-1347-2020, 2020
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Here we compare and contrast results from five well-studied Arctic field sites in order to understand how glaciers affect marine biogeochemistry and marine primary production. The key questions are listed as follows. Where and when does glacial freshwater discharge promote or reduce marine primary production? How does spatio-temporal variability in glacial discharge affect marine primary production? And how far-reaching are the effects of glacial discharge on marine biogeochemistry?
Sarah U. Neuhaus, Slawek M. Tulaczyk, and Carolyn Branecky Begeman
The Cryosphere, 13, 1785–1799, https://doi.org/10.5194/tc-13-1785-2019, https://doi.org/10.5194/tc-13-1785-2019, 2019
Short summary
Short summary
Relatively few studies have been carried out on icebergs inside fjords, despite the fact that the majority of recent sea level rise has resulted from glaciers terminating in fjords. We examine the size and spatial distribution of icebergs in Columbia Fjord, Alaska, over a period of 8 months to determine their influence on fjord dynamics.
Cited articles
Åström, J. A., Vallot, D., Schäfer, M., Welty, E. Z., O'Neel, S., Bartholomaus, T. C., Liu, Y., Riikilä, T. I., Zwinger, T., Timonen, J., and Moore, J. C.: Termini of calving glaciers as self-organized critical
systems, Nat. Geosci., 7, 874–878, 2014. a
Benn, D. I., Warren, C. R., and Mottram, R. H.: Calving processes and the dynamics of calving glaciers, Earth-Sci. Rev., 82, 143–179, 2007. a
Bühler, O.: Impulsive fluid forcing and water strider locomotion, J. Fluid Mech., 573, 211–236, 2007. a
Carr, J. R., Stokes, C. R., and Vieli, A.: Threefold increase in marine-terminating outlet glacier retreat rates across the Atlantic Arctic: 1992–2010, Ann. Glaciol., 58, 72–91, 2017. a
Carroll, D., Sutherland, D. A., Shroyer, E. L., Nash, J. D., Catania, G. A., and Stearns, L. A.: Modeling turbulent subglacial meltwater plumes: implications for fjord-scale buoyancy-driven circulation, J. Phys. Oceanogr., 45, 2169–2185, 2015. a
Carroll, D., Sutherland, D. A., Hudson, B., Moon, T., Catania, G. A., Shroyer, E. L., Nash, J. D., Bartholomaus, T. C., Felikson, D., Stearns, L. A., Noel, B. P. Y., and van den Broeke, M. R.: The impact of glacier geometry on
meltwater plume structure and submarine melt in Greenland fjords, Geophys. Res. Lett., 43, 9739–9748, 2016. a
Cowton, T. R., Slater, D. A., Sole, A. J., Goldberg, D. N., and Nienow, P.: Modeling the impact of glacial runoff on fjord circulation and submarine melt
rate using a new subgrid-scale parameterization for glacial plumes, J. Geophys. Res.-Oceans, 120, 796–812, 2015. a
Ezhova, E., Cenedese, C., and Brandt, L.: Dynamics of Three-Dimensional
Turbulent Wall Plumes and Implications for Estimates of Submarine Glacier Melting, J. Phys. Oceanogr., 48, 1941–1950, 2018. a
Hill, E. A., Carr, J. R., and Stokes, C. R.: A review of recent changes in major marine-terminating outlet glaciers in northern greenland, Front. Earth Sci., 4, 111, https://doi.org/10.3389/feart.2016.00111, 2017. a
Holland, D. M., Thomas, R. H., De Young, B., Ribergaard, M. H., and Lyberth, B.: Acceleration of Jakobshavn Isbrae triggered by warm subsurface ocean
waters, Nat. Geosci., 1, 659–664, 2008. a
Howat, I. M., Joughin, I., and Scambos, T. A.: Rapid changes in ice discharge from Greenland outlet glaciers, Science, 315, 1559–1561, 2007. a
Howat, I. M., Joughin, I., Fahnestock, M., Smith, B. E., and Scambos, T. A.: Synchronous retreat and acceleration of southeast Greenland outlet glaciers 2000–06: ice dynamics and coupling to climate, J. Glaciol., 54, 646–660, 2008. a
Jackson, R. H. and Straneo, F.: Heat, salt, and freshwater budgets for a glacial fjord in Greenland, J. Phys. Oceanogr.,
46, 2735–2768, 2016. a
Jenkins, A.: Convection-Driven Melting near the Grounding Lines of Ice Shelves and Tidewater Glaciers, J. Phys. Oceanogr., 41, 2279–2294, 2011. a
Jenkins, A. and Nicholls, K.: Observation and parameterization of ablation at the base of Ronne Ice Shelf, Antarctica, J. Phys. Oceanogr., 40, 2298–2313, 2010. a
Jensen, T. S., Box, J. E., and Hvidberg, C. S.: A sensitivity study of annual area change for Greenland ice sheet marine terminating outlet glaciers: 1999–2013, J. Glaciol., 62, 72–81, 2016. a
Joughin, I., Smith, B., Howat, I., and Scambos, T.: MEaSUREs Greenland Ice Sheet Velocity Map from InSAR Data, Version 1, Boulder, Colorado USA, NASA National Snow and Ice Data Center Distributed Active Archive Center, https://doi.org/10.5067/MEASURES/CRYOSPHERE/nsidc-0478.001 (last access: 8 March 2019), 2010. a, b
Joughin, I., Alley, R. B., and Holland, D. M.: Ice-Sheet Response to Oceanic Forcing, Science, 338, 1172–1176, 2012. a
Kimball, P., Bailey, J., Das, S., Geyer, R., Harrison, T., Kunz, C.,
Manganini, K., Mankoff, K., Samuelson, K., Sayre-McCord, T., Straneo, F.,
Traykovski, P., and Singh, H.: The WHOI Jetyak: An autonomous surface
vehicle for oceanographic research in shallow or dangerous waters, in: 2014
IEEE/OES Autonomous Underwater Vehicles (AUV), Oxford, MS, USA, 6–9 October
2014, IEEE, 1–7, https://doi.org/10.1109/AUV.2014.7054430, 2014. a, b, c
Luckman, A., Benn, D. I., Cottier, F., Bevan, S., Nilsen, F., and Inall, M.: Calving rates at tidewater glaciers vary strongly with ocean temperature, Nat. Commun., 6, 8566, https://doi.org/10.1038/ncomms9566, 2015. a
Meier, M. F. and Post, A.: Fast tidewater glaciers, J. Geophys. Res., 92, 9051–9058, 1987. a
Moon, T., Joughin, I., Smith, B., and Howat, I.: 21st-Century Evolution of Greenland Outlet Glacier Velocities, Science, 336, 576–578, 2012. a
Morton, B. R., Sir Geoffrey Taylor, F. R. S., and Turner, J. S.: Turbulent gravitational convection from maintained and instantaneous sources, P. Roy. Soc. Lond. A Mat., 234, 1–23, 1956. a
Nick, F. M., Vieli, A., Howat, I. M., and Joughin, I.: Large-scale changes in Greenland outlet glacier dynamics triggered at the terminus, Nat. Geosci., 2, 110–114, 2009. a
Nick, F. M., Vieli, A., Andersen, M. L., Joughin, I., Payne, A., Edwards, T. L., Pattyn, F., and van de Wal, R. S. W.: Future sea-level rise from Greenland's main outlet glaciers in a warming climate, Nature, 497, 235–238, 2013. a
Rignot, E. and Thomas, R. H.: Mass balance of polar ice sheets, Science,
297, 1502–1506, 2002. a
Rignot, E., Xu, Y., Menemenlis, D., Mouginot, J., Scheuchl, B., Li, X.,
Morlighem, M., Seroussi, H., van den Broeke, M., Fenty, I., Cai, C., An, L.,
and de Fleurian, B.: Modeling of ocean-induced ice melt rates of five west
Greenland glaciers over the past two decades, Geophys. Res. Lett., 43,
6374–6382, 2016. a
Robertson, C. M., Benn, D. I., Brook, M. S., Fuller, I. C., and Holt, K. A.: Subaqueous calving margin morphology at Mueller, Hooker and Tasman glaciers
in Aoraki/Mount Cook National Park, New Zealand, J. Glaciol., 58, 1037–1046, 2012. a
Sciascia, R., Straneo, F., Cenedese, C., and Heimbach, P.: Seasonal variability of submarine melt rate and circulation in an East Greenland fjord, J. Geophys. Res.-Oceans, 118, 2492–2506, 2013. a
Silva, T. A. M., Bigg, G. R., and Nicholls, K. W.: Contribution of giant icebergs to the Southern Ocean freshwater flux, J. Geophys. Res., 111, C03004, https://doi.org/10.1029/2004JC002843, 2006. a
Slater, D. A., Goldberg, D. N., Nienow, P. W., and Cowton, T. R.: Scalings for submarine melting at tidewater glaciers from buoyant plume theory, J. Phys. Oceanogr., 46, 1839–1855, 2016. a
Slater, D. A., Nienow, P. W., Goldberg, D. N., Cowton, T. R., and Sole, A. J.: A model for tidewater glacier undercutting by submarine melting, Geophys. Res. Lett., 44, 2360–2368, 2017. a
Stevens, L. A., Straneo, F., Das, S. B., Plueddemann, A. J., Kukulya, A. L., and Morlighem, M.: Linking glacially modified waters to catchment-scale subglacial discharge using autonomous underwater vehicle observations, The Cryosphere, 10, 417–432, https://doi.org/10.5194/tc-10-417-2016, 2016. a, b, c, d, e, f
Straneo, F.: Temperature and salinity profiles adjacent to a tidewater glacier in Sarqardleq Fjord, West Greenland, collected during July 2013, Arctic Data Center, https://doi.org/10.18739/A2B853H78., 2019. a
Straneo, F. and Cenedese, C.: The Dynamics of Greenland's Glacial Fjords and
Their Role in Climate, Annu. Rev. Mar. Sci., 7, 89–112, 2015. a
Straneo, F. and Richards, C.: Detecting Glacier Calving Events from Ocean Waves and Underwater Acoustics, Saqardleq fjord, West Greenland 2013, Arctic Data Center, https://doi.org/10.18739/A24Q7QP6V, 2018. a
Straneo, F., Richards, C., and Holte, J.: Eastward and northward components of ocean current profiles from ADCP taken from small boat in Sarqardleq Fjord adjacent to a tidewater glacier, West Greenland from 2013-07-25 to 2013-07-27 (NCEI Accession 0177127), Version 1.1, NOAA National Centers for Environmental Information, dataset, last access: 8 March 2019, 2018. a
Sugiyama, S., Minowa, M., and Schaefer, M.: Underwater ice terrace observed
at the front of Glaciar Grey, a freshwater calving glacier in Patagonia,
Geophys. Res. Lett., 46, https://doi.org/10.1029/2018GL081441, online first, 2019. a
Veitch, S. A. and Nettles, M.: Spatial and temporal variations in Greenland
glacial-earthquake activity, 1993–2010, J. Geophys. Res., 117, F04007,
https://doi.org/10.1029/2012JF002412, 2012. a
Vieli, A. and Nick, F. M.: Understanding and Modelling Rapid Dynamic Changes
of Tidewater Outlet Glaciers: Issues and Implications, Surv. Geophys., 32,
437–458, 2011. a
Wilson, N., Straneo, F., and Heimbach, P.: Satellite-derived submarine melt
rates and mass balance (2011–2015) for Greenland's largest remaining ice
tongues, The Cryosphere, 11, 2773–2782, https://doi.org/10.5194/tc-11-2773-2017, 2017. a
Xu, Y., Rignot, E., Menemenlis, D., and Koppes, M.: Numerical experiments on
subaqueous melting of Greenland tidewater glaciers in response to ocean
warming and enhanced subglacial discharge, Ann. Glaciol., 53, 229–234, 2012. a
Short summary
This study shows how complex and varied the processes are that determine the frontal position of tidewater glaciers. Rather than uniform melt or calving rates, a single (medium-sized) glacier can feature regions that retreat almost exclusively due to melting and other regions that retreat only due to calving. This has far-reaching consequences for our understanding of how glaciers retreat or advance.
This study shows how complex and varied the processes are that determine the frontal position of...