A general theory of glacier surges
Abstract We present the first general theory of glacier surging that includes both temperate and polythermal glacier surges, based on coupled mass and enthalpy budgets. Enthalpy (in the form of thermal energy and water) is gained at the glacier bed from geothermal heating plus frictional heating (ex...
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Cambridge University Press (CUP)
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Online Access: | http://dx.doi.org/10.1017/jog.2019.62 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143019000625 |
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crcambridgeupr:10.1017/jog.2019.62 2024-09-30T14:37:51+00:00 A general theory of glacier surges Benn, D. I. Fowler, A. C. Hewitt, I. Sevestre, H. 2019 http://dx.doi.org/10.1017/jog.2019.62 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143019000625 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 65, issue 253, page 701-716 ISSN 0022-1430 1727-5652 journal-article 2019 crcambridgeupr https://doi.org/10.1017/jog.2019.62 2024-09-11T04:04:31Z Abstract We present the first general theory of glacier surging that includes both temperate and polythermal glacier surges, based on coupled mass and enthalpy budgets. Enthalpy (in the form of thermal energy and water) is gained at the glacier bed from geothermal heating plus frictional heating (expenditure of potential energy) as a consequence of ice flow. Enthalpy losses occur by conduction and loss of meltwater from the system. Because enthalpy directly impacts flow speeds, mass and enthalpy budgets must simultaneously balance if a glacier is to maintain a steady flow. If not, glaciers undergo out-of-phase mass and enthalpy cycles, manifest as quiescent and surge phases. We illustrate the theory using a lumped element model, which parameterizes key thermodynamic and hydrological processes, including surface-to-bed drainage and distributed and channelized drainage systems. Model output exhibits many of the observed characteristics of polythermal and temperate glacier surges, including the association of surging behaviour with particular combinations of climate (precipitation, temperature), geometry (length, slope) and bed properties (hydraulic conductivity). Enthalpy balance theory explains a broad spectrum of observed surging behaviour in a single framework, and offers an answer to the wider question of why the majority of glaciers do not surge. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Journal of Glaciology 65 253 701 716 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract We present the first general theory of glacier surging that includes both temperate and polythermal glacier surges, based on coupled mass and enthalpy budgets. Enthalpy (in the form of thermal energy and water) is gained at the glacier bed from geothermal heating plus frictional heating (expenditure of potential energy) as a consequence of ice flow. Enthalpy losses occur by conduction and loss of meltwater from the system. Because enthalpy directly impacts flow speeds, mass and enthalpy budgets must simultaneously balance if a glacier is to maintain a steady flow. If not, glaciers undergo out-of-phase mass and enthalpy cycles, manifest as quiescent and surge phases. We illustrate the theory using a lumped element model, which parameterizes key thermodynamic and hydrological processes, including surface-to-bed drainage and distributed and channelized drainage systems. Model output exhibits many of the observed characteristics of polythermal and temperate glacier surges, including the association of surging behaviour with particular combinations of climate (precipitation, temperature), geometry (length, slope) and bed properties (hydraulic conductivity). Enthalpy balance theory explains a broad spectrum of observed surging behaviour in a single framework, and offers an answer to the wider question of why the majority of glaciers do not surge. |
format |
Article in Journal/Newspaper |
author |
Benn, D. I. Fowler, A. C. Hewitt, I. Sevestre, H. |
spellingShingle |
Benn, D. I. Fowler, A. C. Hewitt, I. Sevestre, H. A general theory of glacier surges |
author_facet |
Benn, D. I. Fowler, A. C. Hewitt, I. Sevestre, H. |
author_sort |
Benn, D. I. |
title |
A general theory of glacier surges |
title_short |
A general theory of glacier surges |
title_full |
A general theory of glacier surges |
title_fullStr |
A general theory of glacier surges |
title_full_unstemmed |
A general theory of glacier surges |
title_sort |
general theory of glacier surges |
publisher |
Cambridge University Press (CUP) |
publishDate |
2019 |
url |
http://dx.doi.org/10.1017/jog.2019.62 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143019000625 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 65, issue 253, page 701-716 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2019.62 |
container_title |
Journal of Glaciology |
container_volume |
65 |
container_issue |
253 |
container_start_page |
701 |
op_container_end_page |
716 |
_version_ |
1811640623016443904 |