Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation
Ice deformation and basal motion characterize the dynamical behavior of the Greenland ice sheet (GrIS). We evaluate the contribution of basal motion from ice deformation measurements in boreholes drilled to the bed at two sites in the western marginal zone of the GrIS. We find a sustained high amoun...
Published in: | Journal of Glaciology |
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Main Authors: | , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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2014
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Online Access: | https://orbit.dtu.dk/en/publications/04bfbd46-8f21-4795-a223-25f3493176ac https://doi.org/10.3189/2014JoG13J196 |
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ftdtupubl:oai:pure.atira.dk:publications/04bfbd46-8f21-4795-a223-25f3493176ac 2024-05-19T07:41:12+00:00 Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation Ryser, Claudia Luethi, Martin P. Andrews, Lauren C. Hoffman, Matthew J. Catania, Ginny A. Hawley, Robert L. Neumann, Thomas A. Kristensen, Steen Savstrup 2014 https://orbit.dtu.dk/en/publications/04bfbd46-8f21-4795-a223-25f3493176ac https://doi.org/10.3189/2014JoG13J196 eng eng https://orbit.dtu.dk/en/publications/04bfbd46-8f21-4795-a223-25f3493176ac info:eu-repo/semantics/restrictedAccess Ryser , C , Luethi , M P , Andrews , L C , Hoffman , M J , Catania , G A , Hawley , R L , Neumann , T A & Kristensen , S S 2014 , ' Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation ' , Journal of Glaciology , vol. 60 , no. 222 , pp. 647-660 . https://doi.org/10.3189/2014JoG13J196 article 2014 ftdtupubl https://doi.org/10.3189/2014JoG13J196 2024-04-24T00:35:24Z Ice deformation and basal motion characterize the dynamical behavior of the Greenland ice sheet (GrIS). We evaluate the contribution of basal motion from ice deformation measurements in boreholes drilled to the bed at two sites in the western marginal zone of the GrIS. We find a sustained high amount of basal motion contribution to surface velocity of 44-73% in winter, and up to 90% in summer. Measured ice deformation rates show an unexpected variation with depth that can be explained with the help of an ice-flow model as a consequence of stress transfer from slippery to sticky areas. This effect necessitates the use of high-order ice-flow models, not only in regions of fast-flowing ice streams but in all temperate-based areas of the GrIS. The agreement between modeled and measured deformation rates confirms that the recommended values of the temperature-dependent flow rate factor A are a good choice for ice-sheet models. Article in Journal/Newspaper Greenland Ice Sheet Journal of Glaciology Technical University of Denmark: DTU Orbit Journal of Glaciology 60 222 647 660 |
institution |
Open Polar |
collection |
Technical University of Denmark: DTU Orbit |
op_collection_id |
ftdtupubl |
language |
English |
description |
Ice deformation and basal motion characterize the dynamical behavior of the Greenland ice sheet (GrIS). We evaluate the contribution of basal motion from ice deformation measurements in boreholes drilled to the bed at two sites in the western marginal zone of the GrIS. We find a sustained high amount of basal motion contribution to surface velocity of 44-73% in winter, and up to 90% in summer. Measured ice deformation rates show an unexpected variation with depth that can be explained with the help of an ice-flow model as a consequence of stress transfer from slippery to sticky areas. This effect necessitates the use of high-order ice-flow models, not only in regions of fast-flowing ice streams but in all temperate-based areas of the GrIS. The agreement between modeled and measured deformation rates confirms that the recommended values of the temperature-dependent flow rate factor A are a good choice for ice-sheet models. |
format |
Article in Journal/Newspaper |
author |
Ryser, Claudia Luethi, Martin P. Andrews, Lauren C. Hoffman, Matthew J. Catania, Ginny A. Hawley, Robert L. Neumann, Thomas A. Kristensen, Steen Savstrup |
spellingShingle |
Ryser, Claudia Luethi, Martin P. Andrews, Lauren C. Hoffman, Matthew J. Catania, Ginny A. Hawley, Robert L. Neumann, Thomas A. Kristensen, Steen Savstrup Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation |
author_facet |
Ryser, Claudia Luethi, Martin P. Andrews, Lauren C. Hoffman, Matthew J. Catania, Ginny A. Hawley, Robert L. Neumann, Thomas A. Kristensen, Steen Savstrup |
author_sort |
Ryser, Claudia |
title |
Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation |
title_short |
Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation |
title_full |
Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation |
title_fullStr |
Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation |
title_full_unstemmed |
Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation |
title_sort |
sustained high basal motion of the greenland ice sheet revealed by borehole deformation |
publishDate |
2014 |
url |
https://orbit.dtu.dk/en/publications/04bfbd46-8f21-4795-a223-25f3493176ac https://doi.org/10.3189/2014JoG13J196 |
genre |
Greenland Ice Sheet Journal of Glaciology |
genre_facet |
Greenland Ice Sheet Journal of Glaciology |
op_source |
Ryser , C , Luethi , M P , Andrews , L C , Hoffman , M J , Catania , G A , Hawley , R L , Neumann , T A & Kristensen , S S 2014 , ' Sustained high basal motion of the Greenland ice sheet revealed by borehole deformation ' , Journal of Glaciology , vol. 60 , no. 222 , pp. 647-660 . https://doi.org/10.3189/2014JoG13J196 |
op_relation |
https://orbit.dtu.dk/en/publications/04bfbd46-8f21-4795-a223-25f3493176ac |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.3189/2014JoG13J196 |
container_title |
Journal of Glaciology |
container_volume |
60 |
container_issue |
222 |
container_start_page |
647 |
op_container_end_page |
660 |
_version_ |
1799480804734140416 |