The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier
In cold and arid climates, small glaciers with cold accumulation zones are often thought to be entirely cold based. However, scattering in ground-penetrating radar (GPR) measurements on the Rikha Samba Glacier in the Nepal Himalayas suggests a large amount of temperate ice that seems to be influence...
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Copernicus Publications under license by EGU – European Geosciences Union GmbH
2021
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ftoslouniv:oai:www.duo.uio.no:10852/85751 2023-05-15T18:32:12+02:00 The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier Gilbert, Adrien Sinisalo, Anna Gurung, Tika R. Fujita, Koji Maharjan, Sudan B. Sherpa, Tenzing C. Fukuda, Takehiro 2021-03-19T18:46:22Z http://hdl.handle.net/10852/85751 http://urn.nb.no/URN:NBN:no-88420 https://doi.org/10.5194/tc-14-1273-2020 EN eng Copernicus Publications under license by EGU – European Geosciences Union GmbH http://urn.nb.no/URN:NBN:no-88420 Gilbert, Adrien Sinisalo, Anna Gurung, Tika R. Fujita, Koji Maharjan, Sudan B. Sherpa, Tenzing C. Fukuda, Takehiro . The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier. The Cryosphere. 2020, 14(4), 1273-1288 http://hdl.handle.net/10852/85751 1899544 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=The Cryosphere&rft.volume=14&rft.spage=1273&rft.date=2020 The Cryosphere 14 4 1273 1288 https://doi.org/10.5194/tc-14-1273-2020 URN:NBN:no-88420 Fulltext https://www.duo.uio.no/bitstream/handle/10852/85751/2/tc-14-1273-2020.pdf Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/ CC-BY 1994-0416 Journal article Tidsskriftartikkel Peer reviewed PublishedVersion 2021 ftoslouniv https://doi.org/10.5194/tc-14-1273-2020 2021-05-05T22:31:00Z In cold and arid climates, small glaciers with cold accumulation zones are often thought to be entirely cold based. However, scattering in ground-penetrating radar (GPR) measurements on the Rikha Samba Glacier in the Nepal Himalayas suggests a large amount of temperate ice that seems to be influenced by the presence of crevassed areas. We used a coupled thermo-mechanical model forced by a firn model accounting for firn heating to interpret the observed thermal regime. Using a simple energy conservation approach, we show that the addition of water percolation and refreezing in crevassed areas explains these observations. Model experiments show that both steady and transient thermal regimes are significantly affected by latent heat release in crevassed areas. This makes half of the glacier base temperate, resulting in an ice dynamic mainly controlled by basal friction instead of ice deformation. The timescale of thermal regime change, in response to atmospheric warming, is also greatly diminished, with a potential switch from cold to temperate basal ice in 50–60 years in the upper part of the glacier instead of the 100–150 years that it would take without the effect of the crevasses. This study highlights the crucial role of water percolation through the crevasses on the thermal regime of glaciers and validates a simple method to account for it in glacier thermo-mechanical models. Article in Journal/Newspaper The Cryosphere Universitet i Oslo: Digitale utgivelser ved UiO (DUO) The Cryosphere 14 4 1273 1288 |
institution |
Open Polar |
collection |
Universitet i Oslo: Digitale utgivelser ved UiO (DUO) |
op_collection_id |
ftoslouniv |
language |
English |
description |
In cold and arid climates, small glaciers with cold accumulation zones are often thought to be entirely cold based. However, scattering in ground-penetrating radar (GPR) measurements on the Rikha Samba Glacier in the Nepal Himalayas suggests a large amount of temperate ice that seems to be influenced by the presence of crevassed areas. We used a coupled thermo-mechanical model forced by a firn model accounting for firn heating to interpret the observed thermal regime. Using a simple energy conservation approach, we show that the addition of water percolation and refreezing in crevassed areas explains these observations. Model experiments show that both steady and transient thermal regimes are significantly affected by latent heat release in crevassed areas. This makes half of the glacier base temperate, resulting in an ice dynamic mainly controlled by basal friction instead of ice deformation. The timescale of thermal regime change, in response to atmospheric warming, is also greatly diminished, with a potential switch from cold to temperate basal ice in 50–60 years in the upper part of the glacier instead of the 100–150 years that it would take without the effect of the crevasses. This study highlights the crucial role of water percolation through the crevasses on the thermal regime of glaciers and validates a simple method to account for it in glacier thermo-mechanical models. |
format |
Article in Journal/Newspaper |
author |
Gilbert, Adrien Sinisalo, Anna Gurung, Tika R. Fujita, Koji Maharjan, Sudan B. Sherpa, Tenzing C. Fukuda, Takehiro |
spellingShingle |
Gilbert, Adrien Sinisalo, Anna Gurung, Tika R. Fujita, Koji Maharjan, Sudan B. Sherpa, Tenzing C. Fukuda, Takehiro The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier |
author_facet |
Gilbert, Adrien Sinisalo, Anna Gurung, Tika R. Fujita, Koji Maharjan, Sudan B. Sherpa, Tenzing C. Fukuda, Takehiro |
author_sort |
Gilbert, Adrien |
title |
The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier |
title_short |
The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier |
title_full |
The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier |
title_fullStr |
The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier |
title_full_unstemmed |
The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier |
title_sort |
influence of water percolation through crevasses on the thermal regime of a himalayan mountain glacier |
publisher |
Copernicus Publications under license by EGU – European Geosciences Union GmbH |
publishDate |
2021 |
url |
http://hdl.handle.net/10852/85751 http://urn.nb.no/URN:NBN:no-88420 https://doi.org/10.5194/tc-14-1273-2020 |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
1994-0416 |
op_relation |
http://urn.nb.no/URN:NBN:no-88420 Gilbert, Adrien Sinisalo, Anna Gurung, Tika R. Fujita, Koji Maharjan, Sudan B. Sherpa, Tenzing C. Fukuda, Takehiro . The influence of water percolation through crevasses on the thermal regime of a Himalayan mountain glacier. The Cryosphere. 2020, 14(4), 1273-1288 http://hdl.handle.net/10852/85751 1899544 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=The Cryosphere&rft.volume=14&rft.spage=1273&rft.date=2020 The Cryosphere 14 4 1273 1288 https://doi.org/10.5194/tc-14-1273-2020 URN:NBN:no-88420 Fulltext https://www.duo.uio.no/bitstream/handle/10852/85751/2/tc-14-1273-2020.pdf |
op_rights |
Attribution 4.0 International https://creativecommons.org/licenses/by/4.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/tc-14-1273-2020 |
container_title |
The Cryosphere |
container_volume |
14 |
container_issue |
4 |
container_start_page |
1273 |
op_container_end_page |
1288 |
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1766216275181174784 |