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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COPERNICUS GESELLSCHAFT MBH
2018
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Online Access: | https://epic.awi.de/id/eprint/48794/ https://epic.awi.de/id/eprint/48794/1/tc-12-3931-2018.pdf https://hdl.handle.net/10013/epic.00772f69-0d29-4583-bee1-5b0acfa223c1 |
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ftawi:oai:epic.awi.de:48794 2024-09-15T18:09:24+00:00 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 application/pdf https://epic.awi.de/id/eprint/48794/ https://epic.awi.de/id/eprint/48794/1/tc-12-3931-2018.pdf https://hdl.handle.net/10013/epic.00772f69-0d29-4583-bee1-5b0acfa223c1 unknown COPERNICUS GESELLSCHAFT MBH https://epic.awi.de/id/eprint/48794/1/tc-12-3931-2018.pdf Beyer, S. orcid:0000-0002-3731-0278 , Kleiner, T. orcid:0000-0001-7825-5765 , Aizinger, V. orcid:0000-0002-1061-3084 , Rückamp, M. orcid:0000-0003-2512-7238 and Humbert, A. (2018) A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream , The Cryosphere, 12 (12), pp. 3931-3947 . doi:10.5194/tc-12-3931-2018 <https://doi.org/10.5194/tc-12-3931-2018> , hdl:10013/epic.00772f69-0d29-4583-bee1-5b0acfa223c1 EPIC3The Cryosphere, COPERNICUS GESELLSCHAFT MBH, 12(12), pp. 3931-3947, ISSN: 1994-0424 Article isiRev 2018 ftawi https://doi.org/10.5194/tc-12-3931-2018 2024-06-24T04:21:00Z 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 500km 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 Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) The Cryosphere 12 12 3931 3947 |
institution |
Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
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 500km 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 |
spellingShingle |
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 |
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 GESELLSCHAFT MBH |
publishDate |
2018 |
url |
https://epic.awi.de/id/eprint/48794/ https://epic.awi.de/id/eprint/48794/1/tc-12-3931-2018.pdf https://hdl.handle.net/10013/epic.00772f69-0d29-4583-bee1-5b0acfa223c1 |
genre |
Greenland Ice Sheet The Cryosphere |
genre_facet |
Greenland Ice Sheet The Cryosphere |
op_source |
EPIC3The Cryosphere, COPERNICUS GESELLSCHAFT MBH, 12(12), pp. 3931-3947, ISSN: 1994-0424 |
op_relation |
https://epic.awi.de/id/eprint/48794/1/tc-12-3931-2018.pdf Beyer, S. orcid:0000-0002-3731-0278 , Kleiner, T. orcid:0000-0001-7825-5765 , Aizinger, V. orcid:0000-0002-1061-3084 , Rückamp, M. orcid:0000-0003-2512-7238 and Humbert, A. (2018) A confined–unconfined aquifer model for subglacial hydrology and its application to the Northeast Greenland Ice Stream , The Cryosphere, 12 (12), pp. 3931-3947 . doi:10.5194/tc-12-3931-2018 <https://doi.org/10.5194/tc-12-3931-2018> , hdl:10013/epic.00772f69-0d29-4583-bee1-5b0acfa223c1 |
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 |
_version_ |
1810446941986750464 |