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1. Antarctic Bedmap data: Findable, Accessible, Interoperable, and Reusable (FAIR) sharing of 60 years of ice bed, surface, and thickness data

Author

Frémand, Alice C., primary, Fretwell, Peter, additional, Bodart, Julien A., additional, Pritchard, Hamish D., additional, Aitken, Alan, additional, Bamber, Jonathan L., additional, Bell, Robin, additional, Bianchi, Cesidio, additional, Bingham, Robert G., additional, Blankenship, Donald D., additional, Casassa, Gino, additional, Catania, Ginny, additional, Christianson, Knut, additional, Conway, Howard, additional, Corr, Hugh F. J., additional, Cui, Xiangbin, additional, Damaske, Detlef, additional, Damm, Volkmar, additional, Drews, Reinhard, additional, Eagles, Graeme, additional, Eisen, Olaf, additional, Eisermann, Hannes, additional, Ferraccioli, Fausto, additional, Field, Elena, additional, Forsberg, René, additional, Franke, Steven, additional, Fujita, Shuji, additional, Gim, Yonggyu, additional, Goel, Vikram, additional, Gogineni, Siva Prasad, additional, Greenbaum, Jamin, additional, Hills, Benjamin, additional, Hindmarsh, Richard C. A., additional, Hoffman, Andrew O., additional, Holmlund, Per, additional, Holschuh, Nicholas, additional, Holt, John W., additional, Horlings, Annika N., additional, Humbert, Angelika, additional, Jacobel, Robert W., additional, Jansen, Daniela, additional, Jenkins, Adrian, additional, Jokat, Wilfried, additional, Jordan, Tom, additional, King, Edward, additional, Kohler, Jack, additional, Krabill, William, additional, Kusk Gillespie, Mette, additional, Langley, Kirsty, additional, Lee, Joohan, additional, Leitchenkov, German, additional, Leuschen, Carlton, additional, Luyendyk, Bruce, additional, MacGregor, Joseph, additional, MacKie, Emma, additional, Matsuoka, Kenichi, additional, Morlighem, Mathieu, additional, Mouginot, Jérémie, additional, Nitsche, Frank O., additional, Nogi, Yoshifumi, additional, Nost, Ole A., additional, Paden, John, additional, Pattyn, Frank, additional, Popov, Sergey V., additional, Rignot, Eric, additional, Rippin, David M., additional, Rivera, Andrés, additional, Roberts, Jason, additional, Ross, Neil, additional, Ruppel, Anotonia, additional, Schroeder, Dustin M., additional, Siegert, Martin J., additional, Smith, Andrew M., additional, Steinhage, Daniel, additional, Studinger, Michael, additional, Sun, Bo, additional, Tabacco, Ignazio, additional, Tinto, Kirsty, additional, Urbini, Stefano, additional, Vaughan, David, additional, Welch, Brian C., additional, Wilson, Douglas S., additional, Young, Duncan A., additional, and Zirizzotti, Achille, additional

Published
2023
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2. Antarctic Bedmap data: Findable, Accessible, Interoperable, and Reusable (FAIR) sharing of 60 years of ice bed, surface, and thickness data

Author

Frémand, Alice C., Fretwell, Peter, Bodart, Julien A., Pritchard, Hamish D., Aitken, Alan, Bamber, Jonathan L., Bell, Robin, Bianchi, Cesido, Bingham, Robert G., Blankenship, Donald D., Casassa, Gino, Catania, Ginny, Christianson, Knut, Conway, Howard, Corr, Hugh F.J., Cui, Xiangbin, Damaske, Detlef, Damm, Volkmar, Drews, Reinhard, Eagles, Graeme, Eisen, Olaf, Eisermann, Hannes, Ferraccioli, Fausto, Field, Elena, Forsberg, René, Franke, Steven, Fujita, Shuji, Gim, Yonggyu, Goel, Vikram, Gogineni, Siva Prasad, Greenbaum, Jamin, Hills, Benjamin, Hindmarsh, Richard C.A., Hoffman, Andrew O., Holmlund, Per, Holschuh, Nicholas, Holt, John W., Horlings, Anneka N., Humbert, Anglika, Jacobel, Robert W., Jansen, Daniela, Jenkins, Adrian, Jokat, Wilfried, Jordan, Tom, King, Edward, Kohler, Jack, Krabill, William, Langley, Kirsty, Lee, Joohan, Leitchenkov, German, Leuschen, Carlton, Luyendyk, Bruce, MacGregor, Joseph, MacKie, Emma, Matsuoka, Kenichi, Morlighem, Mathieu, Mouginot, Jérémie, Nitsche, Frank O., Nogi, Yoshifumi, Nost, Ole A., Paden, John, Pattyn, Frank, Popov, Sergey V., Rignot, Eric, Rippin, David M., Rivera, Andrés, Roberts, Jason, Ross, Neil, Ruppel, Anotonia, Schroeder, Dustin M., Siegert, Martin J., Smith, Andrew M., Steinhage, Daniel, Studinger, Michael, Sun, Bo, Tabacco, Ignazio, Tinto, Kirsty, Urbini, Stefano, Vaughan, David, Welch, Brian C., Wilson, Douglas S., Young, Duncan A., and Zirizzotti, Achille

Abstract

One of the key components of this research has been the mapping of Antarctic bed topography and ice thickness parameters that are crucial for modelling ice flow and hence for predicting future ice loss and the ensuing sea level rise. Supported by the Scientific Committee on Antarctic Research (SCAR), the Bedmap3 Action Group aims not only to produce new gridded maps of ice thickness and bed topography for the international scientific community, but also to standardize and make available all the geophysical survey data points used in producing the Bedmap gridded products. Here, we document the survey data used in the latest iteration, Bedmap3, incorporating and adding to all of the datasets previously used for Bedmap1 and Bedmap2, including ice bed, surface and thickness point data from all Antarctic geophysical campaigns since the 1950s. More specifically, we describe the processes used to standardize and make these and future surveys and gridded datasets accessible under the Findable, Accessible, Interoperable, and Reusable (FAIR) data principles. With the goals of making the gridding process reproducible and allowing scientists to re-use the data freely for their own analysis, we introduce the new SCAR Bedmap Data Portal (https://bedmap.scar.org, last access: 1 March 2023) created to provide unprecedented open access to these important datasets through a web-map interface. We believe that this data release will be a valuable asset to Antarctic research and will greatly extend the life cycle of the data held within it. Data are available from the UK Polar Data Centre: https://data.bas.ac.uk (last access: 5 May 2023​​​​​​​). See the Data availability section for the complete list of datasets.

Published
2023

3. Antarctic Bedmap data: FAIR sharing of 60 years of ice bed, surface and thickness data

Author

Frémand, Alice C., primary, Fretwell, Peter, additional, Bodart, Julien, additional, Pritchard, Hamish D., additional, Aitken, Alan, additional, Bamber, Jonathan L., additional, Bell, Robin, additional, Bianchi, Cesido, additional, Bingham, Robert G., additional, Blankenship, Donald D., additional, Casassa, Gino, additional, Catania, Ginny, additional, Christianson, Knut, additional, Conway, Howard, additional, Corr, Hugh F. J., additional, Cui, Xiangbin, additional, Damaske, Daniel, additional, Damm, Volkmar, additional, Drews, Reinhard, additional, Eagles, Graeme, additional, Eisen, Olaf, additional, Eisermann, Hannes, additional, Ferraccioli, Fausto, additional, Field, Elena, additional, Forsberg, René, additional, Franke, Steven, additional, Fujita, Shuji, additional, Gim, Yonggyu, additional, Goel, Vikram, additional, Gogineni, Siva Prasad, additional, Greenbaum, Jamin, additional, Hills, Benjamin, additional, Hindmarsh, Richard C. A., additional, Holmlund, Per, additional, Holschuh, Nicholas, additional, Holt, John W., additional, Humbert, Angelika, additional, Jacobel, Robert W., additional, Jansen, Daniela, additional, Jenkins, Adrian, additional, Jokat, Wilfried, additional, Jordan, Tom, additional, King, Edward, additional, Kohler, Jack, additional, Krabill, William, additional, Langley, Kirsty, additional, Lee, Joohan, additional, Leitchenkov, German, additional, Leuschen, Carlton, additional, Luyendyk, Bruce, additional, MacGregor, Joseph, additional, MacKie, Emma, additional, Matsuoka, Kenichi, additional, Morlinghem, Mathieu, additional, Mouginot, Jeremie, additional, Nitsche, Frank O., additional, Nogi, Yoshifumi, additional, Nost, Ole A., additional, Paden, John, additional, Pattyn, Frank, additional, Popov, Sergey V., additional, Riger-Kusk, Mette, additional, Rignot, Eric, additional, Rippin, David M., additional, Rivera, Andres, additional, Roberts, Jason, additional, Ross, Neil, additional, Ruppel, Antonia, additional, Schroeder, Dustin M., additional, Siegert, Martin J., additional, Smith, Andrew M., additional, Steinhage, Daniel, additional, Studinger, Michael, additional, Sun, Bo, additional, Tabacco, Ignazio, additional, Tinto, Kirsty, additional, Urbini, Stefano, additional, Vaughan, David, additional, Welch, Brian C., additional, Wilson, Douglas S., additional, Young, Duncan A., additional, and Zirizzotti, Achille, additional

Published
2022
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4. Supplementary material to "Antarctic Bedmap data: FAIR sharing of 60 years of ice bed, surface and thickness data"

Author

Frémand, Alice C., primary, Fretwell, Peter, additional, Bodart, Julien, additional, Pritchard, Hamish D., additional, Aitken, Alan, additional, Bamber, Jonathan L., additional, Bell, Robin, additional, Bianchi, Cesido, additional, Bingham, Robert G., additional, Blankenship, Donald D., additional, Casassa, Gino, additional, Catania, Ginny, additional, Christianson, Knut, additional, Conway, Howard, additional, Corr, Hugh F. J., additional, Cui, Xiangbin, additional, Damaske, Daniel, additional, Damm, Volkmar, additional, Drews, Reinhard, additional, Eagles, Graeme, additional, Eisen, Olaf, additional, Eisermann, Hannes, additional, Ferraccioli, Fausto, additional, Field, Elena, additional, Forsberg, René, additional, Franke, Steven, additional, Fujita, Shuji, additional, Gim, Yonggyu, additional, Goel, Vikram, additional, Gogineni, Siva Prasad, additional, Greenbaum, Jamin, additional, Hills, Benjamin, additional, Hindmarsh, Richard C. A., additional, Holmlund, Per, additional, Holschuh, Nicholas, additional, Holt, John W., additional, Humbert, Angelika, additional, Jacobel, Robert W., additional, Jansen, Daniela, additional, Jenkins, Adrian, additional, Jokat, Wilfried, additional, Jordan, Tom, additional, King, Edward, additional, Kohler, Jack, additional, Krabill, William, additional, Langley, Kirsty, additional, Lee, Joohan, additional, Leitchenkov, German, additional, Leuschen, Carlton, additional, Luyendyk, Bruce, additional, MacGregor, Joseph, additional, MacKie, Emma, additional, Matsuoka, Kenichi, additional, Morlinghem, Mathieu, additional, Mouginot, Jeremie, additional, Nitsche, Frank O., additional, Nogi, Yoshifumi, additional, Nost, Ole A., additional, Paden, John, additional, Pattyn, Frank, additional, Popov, Sergey V., additional, Riger-Kusk, Mette, additional, Rignot, Eric, additional, Rippin, David M., additional, Rivera, Andres, additional, Roberts, Jason, additional, Ross, Neil, additional, Ruppel, Antonia, additional, Schroeder, Dustin M., additional, Siegert, Martin J., additional, Smith, Andrew M., additional, Steinhage, Daniel, additional, Studinger, Michael, additional, Sun, Bo, additional, Tabacco, Ignazio, additional, Tinto, Kirsty, additional, Urbini, Stefano, additional, Vaughan, David, additional, Welch, Brian C., additional, Wilson, Douglas S., additional, Young, Duncan A., additional, and Zirizzotti, Achille, additional

Published
2022
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5. Radar attenuation demonstrates advective cooling in the Siple Coast ice streams.

Author

Hills, Benjamin H., Christianson, Knut, Jacobel, Robert W., Conway, Howard, and Pettersson, Rickard

Subjects
ICE streams, SHEAR strain, RADAR, COOLING, ANALYTICAL solutions, SUBGLACIAL lakes, ICE crystals
Abstract

Ice streams are warmed by shear strain, both vertical shear near the bed and lateral shear at the margins. Warm ice deforms more easily, establishing a positive feedback loop in an ice stream where fast flow leads to warm ice and then to even faster flow. Here, we use radar attenuation measurements to show that the Siple Coast ice streams are colder than previously thought, which we hypothesize is due to along-flow advection of cold ice from upstream. We interpret the attenuation results within the context of previous ice-temperature measurements from nearby sites where hot-water boreholes were drilled. These in-situ temperatures are notably colder than model predictions, both in the ice streams and in an ice-stream shear margin. We then model ice temperature using a 1.5-dimensional numerical model which includes a parameterization for along-flow advection. Compared to analytical solutions, we find depth-averaged temperatures that are colder by 0.7°C in the Bindschadler Ice Stream, 2.7°C in the Kamb Ice Stream and 6.2–8.2°C in the Dragon Shear Margin of Whillans Ice Stream, closer to the borehole measurements at all locations. Modelled cooling corresponds to shear-margin thermal strengthening by 3–3.5 times compared to the warm-ice case, which must be compensated by some other weakening mechanism such as material damage or ice-crystal fabric anisotropy. [ABSTRACT FROM AUTHOR]

Published
2023
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7. Fractures as the main pathways of water flow in temperate glaciers

Author

Fountain, Andrew G., Jacobel, Robert W., Schlichting, Robert, and Jansson, Peter

Subjects
Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Author(s): Andrew G. Fountain (corresponding author) [1]; Robert W. Jacobel [3]; Robert Schlichting [2]; Peter Jansson [4] Understanding the flow of water through the body of a glacier is important, [...]

Published
2005
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8. Radar studies of the West Antarctic ice streams

Author

Jacobel, Robert W

Subjects
Geophysics
Abstract

A collaboration has carried out measurements of ice thickness at the mouth of Ice Streams D and E, West Antarctica, using a surface-based impulse radar. These studies were undertaken as a part of the continuing effort to understand the state of the West Antarctic Ice Sheet and its response to climate change. Thickness measurements will be used in the mass balance calculation currently in progress and to better understand features in the surface topography seen at low-angle sun illumination in the satellite imagery. Results show that the discharge areas of Ice Streams D and E are thickening by approximately 1 meter per year, and thus that these ice streams are likely losing mass. Aperiodic wavelike features in the surface topography are described, which pose interesting questions about migration of the grounding line and ice-stream dynamics.

Published
1993

21. Spatial variation of radar-derived basal conditions on Kamb Ice Stream, West Antarctica

Author

Jacobel, Robert W., Welch, Brian C., Osterhouse, David, Pettersson, Rickard, MacGregor, Joseph A., Jacobel, Robert W., Welch, Brian C., Osterhouse, David, Pettersson, Rickard, and MacGregor, Joseph A.

Abstract

Radar profiles of bed echo intensity can survey conditions at the ice-bed interface and test for the presence or absence of water. However, extracting information about basal conditions from bed echo intensities requires an estimate of the attenuation loss through the ice. We used the relationship between bed echo intensities from constant-offset radar data and ice thickness to estimate depth-averaged attenuation rates at several locations on and near Kamb Ice Stream (KIS), West Antarctica. We found values varying from 29 dB km−1 at Siple Dome to 15 dB km−1 in the main trunk region of KIS, in agreement with a previous measurement and models. Using these attenuation-rate values, we calculated the relative bed reflectivity throughout our KIS surveys and found that most of the bed in the trunk has high basal reflectivities, similar to those obtained in the location of boreholes that found water at the bed. Areas of lower bed reflectivity are limited to the sticky spot, where a borehole found a dry bed, and along the margins of KIS. These results support previous hypotheses that the basal conditions at locations like the sticky spot on KIS control its stagnation and possible reactivation.

Published
2009
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22. Ice sheet grounding zone stabilization due to till compaction

Author

Christianson, Knut, primary, Parizek, Byron R., additional, Alley, Richard B., additional, Horgan, Huw J., additional, Jacobel, Robert W., additional, Anandakrishnan, Sridhar, additional, Keisling, Benjamin A., additional, Craig, Brian D., additional, and Muto, Atsuhiro, additional

Published
2013
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39. Radar observations of a relict ice-stream margin traversing Siple Dome, Antarctica.

Author

Jacobel, Robert W. and Gades, Anthony M.

Subjects
*ICE, *RADAR, *DOMES (Geology), *STRUCTURAL geology
Abstract

Characterizes the summit region ice dynamics and history of Simple Dome, Antarctica for a possible deep-core site and investigates a curvilinear scarlike feature traversing the northeast flank of the dome using the radar. Description of the radar system; Radar observations which prove that the scar is a dynamic boundary; Use of the continuous uppermost layers across the former ice-stream margin.

Published
1995

40. Internal layer folding patterns from radar studies of ice streams B and C.

Author

Jacobel, Robert W. and Grommes, Ben J.

Subjects
*ANTARCTIC ice, *FOLDS (Geology)
Abstract

Presents results of ground-based radar studies on ice fold patterns in Antarctica. Focus on three-dimensional nature of fold structures; Regions limiting pattern observations; Bed topography; Diagrams.

Published
1994

41. Radar studies of ice thickness and surface features at the mouths of ice streams D and E...

Author

Jacobel, Robert W. and Nelson, Kristen E.

Subjects
*RADAR in surveying, *ICE sheets, *SURVEYS
Abstract

Describes radar studies of ice thickness and surface features at the mouths of ice streams in Antarctica. Response of ice sheets to climate change; Determination of ice thickness for mass-balance calculations for the ice streams; Use of radar to investigate surface features in the surface topography observed in Landstat Thematic Mapper images.

Published
1992

45. Estuaries beneath ice sheets.

Author

Horgan, Huw J., Alley, Richard B., Christianson, Knut, Jacobel, Robert W., Anandakrishnan, Sridhar, Muto, Atsuhiro, Beem, Lucas H., and Siegfried, Matthew R.

Subjects
*ESTUARIES, *GEOPHYSICAL observations, *ICE sheets, *SUBGLACIAL lakes, *GLACIOLOGY
Abstract

Interactions between subglacial hydrology and the ocean make the existence of estuaries at the grounding zones of ice sheets likely. Here we present geophysical observations of an estuary at the downstream end of the hydrologic system that links the active subglacial lakes beneath Whillans Ice Stream to the ocean beneath the Ross Ice Shelf, Antarctica. This subglacial estuary consists of a hydropotential low upstream of the grounding zone, which is linked to the ocean by a hydropotential trough and a large subglacial channel. This subglacial channel, which is imaged using active source seismic methods, has an apparent width of 1 km and a maximum depth of 7 m. The hydropotential trough continues upstream of the grounding zone and results from an along-flow depression in surface elevations. Pressure differences along the trough axis are within a range that can be overcome by tidally induced processes, making the interaction of subglacial and ocean water likely. [ABSTRACT FROM AUTHOR]

Published
2013
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