A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream
Subglacial hydrology plays an important role in ice sheet dynamics as it determines the sliding velocity. It also drives freshwater into the ocean, leading to undercutting of calving fronts by plumes. Modeling subglacial water has been a challenge for decades. Only recently have new approaches been...
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00003676 2023-05-15T16:27:52+02:00 A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream Beyer, Sebastian Kleiner, Thomas Aizinger, Vadym Rückamp, Martin Humbert, Angelika 2018-12 electronic https://doi.org/10.5194/tc-12-3931-2018 https://noa.gwlb.de/receive/cop_mods_00003676 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00003634/tc-12-3931-2018.pdf https://tc.copernicus.org/articles/12/3931/2018/tc-12-3931-2018.pdf eng eng Copernicus Publications The Cryosphere -- ˜Theœ Cryosphere -- http://www.bibliothek.uni-regensburg.de/ezeit/?2393169 -- http://www.the-cryosphere.net/ -- 1994-0424 https://doi.org/10.5194/tc-12-3931-2018 https://noa.gwlb.de/receive/cop_mods_00003676 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00003634/tc-12-3931-2018.pdf https://tc.copernicus.org/articles/12/3931/2018/tc-12-3931-2018.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2018 ftnonlinearchiv https://doi.org/10.5194/tc-12-3931-2018 2022-02-08T23:00:30Z Subglacial hydrology plays an important role in ice sheet dynamics as it determines the sliding velocity. It also drives freshwater into the ocean, leading to undercutting of calving fronts by plumes. Modeling subglacial water has been a challenge for decades. Only recently have new approaches been developed such as representing subglacial channels and thin water sheets by separate layers of variable hydraulic conductivity. We extend this concept by modeling a confined–unconfined aquifer system (CUAS) in a single layer of an equivalent porous medium (EPM). The advantage of this formulation is that it prevents unphysical values of pressure at reasonable computational cost. We performed sensitivity tests to investigate the effect of different model parameters. The strongest influence of model parameters was detected in terms of governing the opening and closure of the system. Furthermore, we applied the model to the Northeast Greenland Ice Stream, where an efficient system independent of seasonal input was identified about 500 km downstream from the ice divide. Using the effective pressure from the hydrology model, the Ice Sheet System Model (ISSM) showed considerable improvements in modeled velocities in the coastal region. Article in Journal/Newspaper Greenland Ice Sheet The Cryosphere Niedersächsisches Online-Archiv NOA Greenland The Cryosphere 12 12 3931 3947 |
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English |
topic |
article Verlagsveröffentlichung |
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article Verlagsveröffentlichung Beyer, Sebastian Kleiner, Thomas Aizinger, Vadym Rückamp, Martin Humbert, Angelika A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream |
topic_facet |
article Verlagsveröffentlichung |
description |
Subglacial hydrology plays an important role in ice sheet dynamics as it determines the sliding velocity. It also drives freshwater into the ocean, leading to undercutting of calving fronts by plumes. Modeling subglacial water has been a challenge for decades. Only recently have new approaches been developed such as representing subglacial channels and thin water sheets by separate layers of variable hydraulic conductivity. We extend this concept by modeling a confined–unconfined aquifer system (CUAS) in a single layer of an equivalent porous medium (EPM). The advantage of this formulation is that it prevents unphysical values of pressure at reasonable computational cost. We performed sensitivity tests to investigate the effect of different model parameters. The strongest influence of model parameters was detected in terms of governing the opening and closure of the system. Furthermore, we applied the model to the Northeast Greenland Ice Stream, where an efficient system independent of seasonal input was identified about 500 km downstream from the ice divide. Using the effective pressure from the hydrology model, the Ice Sheet System Model (ISSM) showed considerable improvements in modeled velocities in the coastal region. |
format |
Article in Journal/Newspaper |
author |
Beyer, Sebastian Kleiner, Thomas Aizinger, Vadym Rückamp, Martin Humbert, Angelika |
author_facet |
Beyer, Sebastian Kleiner, Thomas Aizinger, Vadym Rückamp, Martin Humbert, Angelika |
author_sort |
Beyer, Sebastian |
title |
A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream |
title_short |
A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream |
title_full |
A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream |
title_fullStr |
A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream |
title_full_unstemmed |
A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream |
title_sort |
confined–unconfined aquifer model for subglacial hydrology and its application to the northeast greenland ice stream |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-12-3931-2018 https://noa.gwlb.de/receive/cop_mods_00003676 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00003634/tc-12-3931-2018.pdf https://tc.copernicus.org/articles/12/3931/2018/tc-12-3931-2018.pdf |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet The Cryosphere |
genre_facet |
Greenland Ice Sheet The Cryosphere |
op_relation |
The Cryosphere -- ˜Theœ Cryosphere -- http://www.bibliothek.uni-regensburg.de/ezeit/?2393169 -- http://www.the-cryosphere.net/ -- 1994-0424 https://doi.org/10.5194/tc-12-3931-2018 https://noa.gwlb.de/receive/cop_mods_00003676 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00003634/tc-12-3931-2018.pdf https://tc.copernicus.org/articles/12/3931/2018/tc-12-3931-2018.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/tc-12-3931-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
12 |
container_start_page |
3931 |
op_container_end_page |
3947 |
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1766017429513699328 |