Ice flow modelling to constrain the surface mass balance and ice discharge of San Rafael Glacier, Northern Patagonia Icefield
ABSTRACT We simulate the ice dynamics of the San Rafael Glacier (SRG) in the Northern Patagonia Icefield (46.7°S, 73.5°W), using glacier geometry obtained by airborne gravity measurements. The full-Stokes ice flow model (Elmer/Ice) is initialized using an inverse method to infer the basal friction c...
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Language: | English |
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Cambridge University Press (CUP)
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Online Access: | http://dx.doi.org/10.1017/jog.2018.46 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000461 |
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crcambridgeupr:10.1017/jog.2018.46 2024-06-23T07:54:14+00:00 Ice flow modelling to constrain the surface mass balance and ice discharge of San Rafael Glacier, Northern Patagonia Icefield COLLAO-BARRIOS, GABRIELA GILLET-CHAULET, FABIEN FAVIER, VINCENT CASASSA, GINO BERTHIER, ETIENNE DUSSAILLANT, INÉS MOUGINOT, JÉRÉMIE RIGNOT, ERIC 2018 http://dx.doi.org/10.1017/jog.2018.46 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000461 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 64, issue 246, page 568-582 ISSN 0022-1430 1727-5652 journal-article 2018 crcambridgeupr https://doi.org/10.1017/jog.2018.46 2024-05-29T08:10:00Z ABSTRACT We simulate the ice dynamics of the San Rafael Glacier (SRG) in the Northern Patagonia Icefield (46.7°S, 73.5°W), using glacier geometry obtained by airborne gravity measurements. The full-Stokes ice flow model (Elmer/Ice) is initialized using an inverse method to infer the basal friction coefficient from a satellite-derived surface velocity mosaic. The high surface velocities (7.6 km a −1 ) near the glacier front are explained by low basal shear stresses (<25 kPa). The modelling results suggest that 98% of the surface velocities are due to basal sliding in the fast-flowing glacier tongue (>1 km a −1 ). We force the model using different surface mass-balance scenarios taken or adapted from previous studies and geodetic elevation changes between 2000 and 2012. Our results suggest that previous estimates of average surface mass balance over the entire glacier ( Ḃ ) were likely too high, mainly due to an overestimation in the accumulation area. We propose that most of SRG imbalance is due to the large ice discharge (−0.83 ± 0.08 Gt a −1 ) and a slightly positive Ḃ (0.08 ± 0.06 Gt a −1 ). The committed mass-loss estimate over the next century is −0.34 ± 0.03 Gt a −1 . This study demonstrates that surface mass-balance estimates and glacier wastage projections can be improved using a physically based ice flow model. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Patagonia Journal of Glaciology 64 246 568 582 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
ABSTRACT We simulate the ice dynamics of the San Rafael Glacier (SRG) in the Northern Patagonia Icefield (46.7°S, 73.5°W), using glacier geometry obtained by airborne gravity measurements. The full-Stokes ice flow model (Elmer/Ice) is initialized using an inverse method to infer the basal friction coefficient from a satellite-derived surface velocity mosaic. The high surface velocities (7.6 km a −1 ) near the glacier front are explained by low basal shear stresses (<25 kPa). The modelling results suggest that 98% of the surface velocities are due to basal sliding in the fast-flowing glacier tongue (>1 km a −1 ). We force the model using different surface mass-balance scenarios taken or adapted from previous studies and geodetic elevation changes between 2000 and 2012. Our results suggest that previous estimates of average surface mass balance over the entire glacier ( Ḃ ) were likely too high, mainly due to an overestimation in the accumulation area. We propose that most of SRG imbalance is due to the large ice discharge (−0.83 ± 0.08 Gt a −1 ) and a slightly positive Ḃ (0.08 ± 0.06 Gt a −1 ). The committed mass-loss estimate over the next century is −0.34 ± 0.03 Gt a −1 . This study demonstrates that surface mass-balance estimates and glacier wastage projections can be improved using a physically based ice flow model. |
format |
Article in Journal/Newspaper |
author |
COLLAO-BARRIOS, GABRIELA GILLET-CHAULET, FABIEN FAVIER, VINCENT CASASSA, GINO BERTHIER, ETIENNE DUSSAILLANT, INÉS MOUGINOT, JÉRÉMIE RIGNOT, ERIC |
spellingShingle |
COLLAO-BARRIOS, GABRIELA GILLET-CHAULET, FABIEN FAVIER, VINCENT CASASSA, GINO BERTHIER, ETIENNE DUSSAILLANT, INÉS MOUGINOT, JÉRÉMIE RIGNOT, ERIC Ice flow modelling to constrain the surface mass balance and ice discharge of San Rafael Glacier, Northern Patagonia Icefield |
author_facet |
COLLAO-BARRIOS, GABRIELA GILLET-CHAULET, FABIEN FAVIER, VINCENT CASASSA, GINO BERTHIER, ETIENNE DUSSAILLANT, INÉS MOUGINOT, JÉRÉMIE RIGNOT, ERIC |
author_sort |
COLLAO-BARRIOS, GABRIELA |
title |
Ice flow modelling to constrain the surface mass balance and ice discharge of San Rafael Glacier, Northern Patagonia Icefield |
title_short |
Ice flow modelling to constrain the surface mass balance and ice discharge of San Rafael Glacier, Northern Patagonia Icefield |
title_full |
Ice flow modelling to constrain the surface mass balance and ice discharge of San Rafael Glacier, Northern Patagonia Icefield |
title_fullStr |
Ice flow modelling to constrain the surface mass balance and ice discharge of San Rafael Glacier, Northern Patagonia Icefield |
title_full_unstemmed |
Ice flow modelling to constrain the surface mass balance and ice discharge of San Rafael Glacier, Northern Patagonia Icefield |
title_sort |
ice flow modelling to constrain the surface mass balance and ice discharge of san rafael glacier, northern patagonia icefield |
publisher |
Cambridge University Press (CUP) |
publishDate |
2018 |
url |
http://dx.doi.org/10.1017/jog.2018.46 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000461 |
geographic |
Patagonia |
geographic_facet |
Patagonia |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 64, issue 246, page 568-582 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2018.46 |
container_title |
Journal of Glaciology |
container_volume |
64 |
container_issue |
246 |
container_start_page |
568 |
op_container_end_page |
582 |
_version_ |
1802646326793469952 |