Variations in the surface velocity of an alpine cirque glacier
ABSTRACT Following pioneering work in Norway, cirque glaciers have widely been viewed as rigidly rotating bodies. This model is incorrect for basin-filling cirque glaciers, as we have demonstrated at West Washmawapta Glacier, a small glacier in the Canadian Rocky Mountains. Here we report observatio...
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Online Access: | http://dx.doi.org/10.1017/jog.2018.85 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000850 |
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crcambridgeupr:10.1017/jog.2018.85 2024-05-19T07:40:46+00:00 Variations in the surface velocity of an alpine cirque glacier SANDERS, J. W. CUFFEY, K. M. MACGREGOR, K. R. KAVANAUGH, J. L. DOW, C. F. 2018 http://dx.doi.org/10.1017/jog.2018.85 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000850 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 64, issue 248, page 969-976 ISSN 0022-1430 1727-5652 journal-article 2018 crcambridgeupr https://doi.org/10.1017/jog.2018.85 2024-05-02T06:50:55Z ABSTRACT Following pioneering work in Norway, cirque glaciers have widely been viewed as rigidly rotating bodies. This model is incorrect for basin-filling cirque glaciers, as we have demonstrated at West Washmawapta Glacier, a small glacier in the Canadian Rocky Mountains. Here we report observations at the same glacier that assess whether complex temporal variations of flow also occur. For parts of three summers, we measured daily displacements of the glacier surface. In one year, four short-duration speed-up events were recorded. Three of the events occurred during the intervals of warmest weather, when melt was most rapid; the fourth event occurred immediately following heavy rain. We interpret the speed-up events as manifestations of enhanced water inputs to the glacier bed and associated slip lubrication by increased water volumes and pressures. No further speed-ups occurred in the final month of the melt season, despite warm temperatures and several rainstorms; the dominant subglacial water system likely transformed from one of poorly connected cavities to one with an efficient channel network. The seasonal evolution of hydrology and flow resembles behaviors documented at other, larger temperate glaciers and indicates that analyses of cirque erosion cannot rely on simple assumptions about ice dynamics. Article in Journal/Newspaper glacier Journal of Glaciology Cambridge University Press Journal of Glaciology 64 248 969 976 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
ABSTRACT Following pioneering work in Norway, cirque glaciers have widely been viewed as rigidly rotating bodies. This model is incorrect for basin-filling cirque glaciers, as we have demonstrated at West Washmawapta Glacier, a small glacier in the Canadian Rocky Mountains. Here we report observations at the same glacier that assess whether complex temporal variations of flow also occur. For parts of three summers, we measured daily displacements of the glacier surface. In one year, four short-duration speed-up events were recorded. Three of the events occurred during the intervals of warmest weather, when melt was most rapid; the fourth event occurred immediately following heavy rain. We interpret the speed-up events as manifestations of enhanced water inputs to the glacier bed and associated slip lubrication by increased water volumes and pressures. No further speed-ups occurred in the final month of the melt season, despite warm temperatures and several rainstorms; the dominant subglacial water system likely transformed from one of poorly connected cavities to one with an efficient channel network. The seasonal evolution of hydrology and flow resembles behaviors documented at other, larger temperate glaciers and indicates that analyses of cirque erosion cannot rely on simple assumptions about ice dynamics. |
format |
Article in Journal/Newspaper |
author |
SANDERS, J. W. CUFFEY, K. M. MACGREGOR, K. R. KAVANAUGH, J. L. DOW, C. F. |
spellingShingle |
SANDERS, J. W. CUFFEY, K. M. MACGREGOR, K. R. KAVANAUGH, J. L. DOW, C. F. Variations in the surface velocity of an alpine cirque glacier |
author_facet |
SANDERS, J. W. CUFFEY, K. M. MACGREGOR, K. R. KAVANAUGH, J. L. DOW, C. F. |
author_sort |
SANDERS, J. W. |
title |
Variations in the surface velocity of an alpine cirque glacier |
title_short |
Variations in the surface velocity of an alpine cirque glacier |
title_full |
Variations in the surface velocity of an alpine cirque glacier |
title_fullStr |
Variations in the surface velocity of an alpine cirque glacier |
title_full_unstemmed |
Variations in the surface velocity of an alpine cirque glacier |
title_sort |
variations in the surface velocity of an alpine cirque glacier |
publisher |
Cambridge University Press (CUP) |
publishDate |
2018 |
url |
http://dx.doi.org/10.1017/jog.2018.85 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000850 |
genre |
glacier Journal of Glaciology |
genre_facet |
glacier Journal of Glaciology |
op_source |
Journal of Glaciology volume 64, issue 248, page 969-976 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2018.85 |
container_title |
Journal of Glaciology |
container_volume |
64 |
container_issue |
248 |
container_start_page |
969 |
op_container_end_page |
976 |
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1799480348892987392 |