Jakobshavns Isbræ, West Greenland: Seasonal Variations in Velocity - or Lack Thereof
Abstract The lower 80 km of the fast-moving Jakobshavns Isbræ, West Greenland, is subject to significant melting during the summer season. The melt water drains into large supraglacial rivers which pour into moulins or feed into beautiful supraglacial lakes, some of which are observed to drain perio...
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Language: | English |
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Cambridge University Press (CUP)
1990
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Online Access: | http://dx.doi.org/10.1017/s0022143000005591 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000005591 |
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crcambridgeupr:10.1017/s0022143000005591 2024-09-15T18:07:40+00:00 Jakobshavns Isbræ, West Greenland: Seasonal Variations in Velocity - or Lack Thereof Echelmeyer, Keith Harrison, William D. 1990 http://dx.doi.org/10.1017/s0022143000005591 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000005591 en eng Cambridge University Press (CUP) Journal of Glaciology volume 36, issue 122, page 82-88 ISSN 0022-1430 1727-5652 journal-article 1990 crcambridgeupr https://doi.org/10.1017/s0022143000005591 2024-07-24T04:03:07Z Abstract The lower 80 km of the fast-moving Jakobshavns Isbræ, West Greenland, is subject to significant melting during the summer season. The melt water drains into large supraglacial rivers which pour into moulins or feed into beautiful supraglacial lakes, some of which are observed to drain periodically. Except for a few streams that drain directly off the margins of the ice sheet within the drainage basin of this glacier, the fate of this melt water is unknown. However, a localized upwelling of highly turbid water is often observed during the melt season in the fjord adjacent Io the terminal cliff of the glacier, indicating that water from some source does move along the glacier bed. As part of an investigation on the mechanisms of rapid flow on Jakobshavns Isbræ, measurements of surface velocity at several (∼25) locations along the ice stream at and below the equilibrium line were made in order to investigate the effects of this seasonally varying input of melt water on the speed of the glacier. No significant seasonal variation in speed was found at any location. This indicates that, unlike many other sub-polar and temperate glaciers, surface melt-water production does not affect the motion of this glacier on a seasonal basis, and, thus, does not cause a significant temporal variation in basal sliding. This finding has important ramifications on the mechanisms of flow for this ice stream. Article in Journal/Newspaper glacier Greenland Ice Sheet Journal of Glaciology Cambridge University Press Journal of Glaciology 36 122 82 88 |
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Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
Abstract The lower 80 km of the fast-moving Jakobshavns Isbræ, West Greenland, is subject to significant melting during the summer season. The melt water drains into large supraglacial rivers which pour into moulins or feed into beautiful supraglacial lakes, some of which are observed to drain periodically. Except for a few streams that drain directly off the margins of the ice sheet within the drainage basin of this glacier, the fate of this melt water is unknown. However, a localized upwelling of highly turbid water is often observed during the melt season in the fjord adjacent Io the terminal cliff of the glacier, indicating that water from some source does move along the glacier bed. As part of an investigation on the mechanisms of rapid flow on Jakobshavns Isbræ, measurements of surface velocity at several (∼25) locations along the ice stream at and below the equilibrium line were made in order to investigate the effects of this seasonally varying input of melt water on the speed of the glacier. No significant seasonal variation in speed was found at any location. This indicates that, unlike many other sub-polar and temperate glaciers, surface melt-water production does not affect the motion of this glacier on a seasonal basis, and, thus, does not cause a significant temporal variation in basal sliding. This finding has important ramifications on the mechanisms of flow for this ice stream. |
format |
Article in Journal/Newspaper |
author |
Echelmeyer, Keith Harrison, William D. |
spellingShingle |
Echelmeyer, Keith Harrison, William D. Jakobshavns Isbræ, West Greenland: Seasonal Variations in Velocity - or Lack Thereof |
author_facet |
Echelmeyer, Keith Harrison, William D. |
author_sort |
Echelmeyer, Keith |
title |
Jakobshavns Isbræ, West Greenland: Seasonal Variations in Velocity - or Lack Thereof |
title_short |
Jakobshavns Isbræ, West Greenland: Seasonal Variations in Velocity - or Lack Thereof |
title_full |
Jakobshavns Isbræ, West Greenland: Seasonal Variations in Velocity - or Lack Thereof |
title_fullStr |
Jakobshavns Isbræ, West Greenland: Seasonal Variations in Velocity - or Lack Thereof |
title_full_unstemmed |
Jakobshavns Isbræ, West Greenland: Seasonal Variations in Velocity - or Lack Thereof |
title_sort |
jakobshavns isbræ, west greenland: seasonal variations in velocity - or lack thereof |
publisher |
Cambridge University Press (CUP) |
publishDate |
1990 |
url |
http://dx.doi.org/10.1017/s0022143000005591 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000005591 |
genre |
glacier Greenland Ice Sheet Journal of Glaciology |
genre_facet |
glacier Greenland Ice Sheet Journal of Glaciology |
op_source |
Journal of Glaciology volume 36, issue 122, page 82-88 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000005591 |
container_title |
Journal of Glaciology |
container_volume |
36 |
container_issue |
122 |
container_start_page |
82 |
op_container_end_page |
88 |
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1810445041389273088 |