Glacier Sliding at Subfreezing Temperatures
Abstract Nye’s theory of glacier sliding, when modified to incorporate Gilpin’s model of the liquid layer adjacent to foreign solids in ice, predicts non-zero sliding speeds at subfreezing temperatures. Although the predicted speeds are too small to affect glacier motion or even to be observed readi...
Published in: | Journal of Glaciology |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1984
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0022143000006195 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006195 |
id |
crcambridgeupr:10.1017/s0022143000006195 |
---|---|
record_format |
openpolar |
spelling |
crcambridgeupr:10.1017/s0022143000006195 2023-06-11T04:13:30+02:00 Glacier Sliding at Subfreezing Temperatures Shreve, R. L. 1984 http://dx.doi.org/10.1017/s0022143000006195 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006195 en eng Cambridge University Press (CUP) Journal of Glaciology volume 30, issue 106, page 341-347 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1984 crcambridgeupr https://doi.org/10.1017/s0022143000006195 2023-05-01T18:20:09Z Abstract Nye’s theory of glacier sliding, when modified to incorporate Gilpin’s model of the liquid layer adjacent to foreign solids in ice, predicts non-zero sliding speeds at subfreezing temperatures. Although the predicted speeds are too small to affect glacier motion or even to be observed readily, the total distance of sliding of large glaciers should be adequate to produce bedrock striations. Dissolved solutes in the liquid layer increase the sliding speeds slightly. At temperatures below about – 1° C, 90% of the drag comes from the part of the bed-roughness spectrum at wavelengths between 0.2 and 20 mm regardless of solute concentration. If no more basal ice melts than refreezes (as in a cold glacier), the average liquid-layer thickness and, concomitantly, the sliding speed for given drag and roughness are governed by the ambient temperature. With net melting (as in a temperate glacier), on the other hand, they are governed by the rate of escape of the excess water and no conflict arises between the thickness requirement for run-off water flow and that for regelation water flow. Thus, the proper distinction is not between temperate and cold, but between net melting and no net melting. The theory applies to both cases. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press (via Crossref) Journal of Glaciology 30 106 341 347 |
institution |
Open Polar |
collection |
Cambridge University Press (via Crossref) |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Shreve, R. L. Glacier Sliding at Subfreezing Temperatures |
topic_facet |
Earth-Surface Processes |
description |
Abstract Nye’s theory of glacier sliding, when modified to incorporate Gilpin’s model of the liquid layer adjacent to foreign solids in ice, predicts non-zero sliding speeds at subfreezing temperatures. Although the predicted speeds are too small to affect glacier motion or even to be observed readily, the total distance of sliding of large glaciers should be adequate to produce bedrock striations. Dissolved solutes in the liquid layer increase the sliding speeds slightly. At temperatures below about – 1° C, 90% of the drag comes from the part of the bed-roughness spectrum at wavelengths between 0.2 and 20 mm regardless of solute concentration. If no more basal ice melts than refreezes (as in a cold glacier), the average liquid-layer thickness and, concomitantly, the sliding speed for given drag and roughness are governed by the ambient temperature. With net melting (as in a temperate glacier), on the other hand, they are governed by the rate of escape of the excess water and no conflict arises between the thickness requirement for run-off water flow and that for regelation water flow. Thus, the proper distinction is not between temperate and cold, but between net melting and no net melting. The theory applies to both cases. |
format |
Article in Journal/Newspaper |
author |
Shreve, R. L. |
author_facet |
Shreve, R. L. |
author_sort |
Shreve, R. L. |
title |
Glacier Sliding at Subfreezing Temperatures |
title_short |
Glacier Sliding at Subfreezing Temperatures |
title_full |
Glacier Sliding at Subfreezing Temperatures |
title_fullStr |
Glacier Sliding at Subfreezing Temperatures |
title_full_unstemmed |
Glacier Sliding at Subfreezing Temperatures |
title_sort |
glacier sliding at subfreezing temperatures |
publisher |
Cambridge University Press (CUP) |
publishDate |
1984 |
url |
http://dx.doi.org/10.1017/s0022143000006195 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000006195 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 30, issue 106, page 341-347 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000006195 |
container_title |
Journal of Glaciology |
container_volume |
30 |
container_issue |
106 |
container_start_page |
341 |
op_container_end_page |
347 |
_version_ |
1768390627561570304 |