Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology
Abstract Jakobshavns Isbræ is a large, fast-moving ice stream/outlet glacier in West Greenland which ends at a floating, calving front. It drains about 6.5% of the area of the Greenland ice sheet. Studies of its surface morphology are described in this paper. The surface is relatively steep (0.01–0....
Published in: | Journal of Glaciology |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1991
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0022143000005803 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000005803 |
id |
crcambridgeupr:10.1017/s0022143000005803 |
---|---|
record_format |
openpolar |
spelling |
crcambridgeupr:10.1017/s0022143000005803 2024-04-28T08:02:44+00:00 Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology Echelmeyer, K. Clarke, T. S. Harrison, W.D. 1991 http://dx.doi.org/10.1017/s0022143000005803 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000005803 en eng Cambridge University Press (CUP) Journal of Glaciology volume 37, issue 127, page 368-382 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1991 crcambridgeupr https://doi.org/10.1017/s0022143000005803 2024-04-09T06:55:39Z Abstract Jakobshavns Isbræ is a large, fast-moving ice stream/outlet glacier in West Greenland which ends at a floating, calving front. It drains about 6.5% of the area of the Greenland ice sheet. Studies of its surface morphology are described in this paper. The surface is relatively steep (0.01–0.03) and the thickness is large (up to 2600 m along the center line (Clarke and Echelmeyer, 1989)), indicating very high driving stresses (200–300 kPa). The ice stream is about 6 km wide and 85–90 km long, all of which is in an area of surface melting. The base of the ice stream, and of much of the drainage area, is below sea level. Marginal crevasse zones have a width on the order of the width of the ice stream itself. Unique surficial features are ice blisters and lakes; the latter have a sequence of ogive-like features on their floating ice cover which can be used to determine velocity. There is a pinning point near the terminus which may act as a stabilizing influence, possibly playing a role in halting, at least temporarily, a recent retreat of the terminus. Ice-thickness estimates at the terminus lead to a flux which is less than previously assumed by others (e.g. Bindschadler, 1984; Pelto and others, 1989) when estimating Jakobshavns Isbræ’s drainage basin to be nearly in balance. The driving stresses on Jakobshavns Isbræ are an order of magnitude higher than those of the ice streams of West Antarctica. Its crevasse patterns are much less localized. Its relatively unconfined terminus is more comparable to that of relatively unbuttressed ice streams such as Pine Island and Thwaites Glaciers than it is to other West Antarctic ice streams which terminate in large, confined ice shelves. Article in Journal/Newspaper Antarc* Antarctic Antarctica glacier Greenland Ice Sheet Ice Shelves Journal of Glaciology Pine Island West Antarctica Cambridge University Press Journal of Glaciology 37 127 368 382 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Echelmeyer, K. Clarke, T. S. Harrison, W.D. Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology |
topic_facet |
Earth-Surface Processes |
description |
Abstract Jakobshavns Isbræ is a large, fast-moving ice stream/outlet glacier in West Greenland which ends at a floating, calving front. It drains about 6.5% of the area of the Greenland ice sheet. Studies of its surface morphology are described in this paper. The surface is relatively steep (0.01–0.03) and the thickness is large (up to 2600 m along the center line (Clarke and Echelmeyer, 1989)), indicating very high driving stresses (200–300 kPa). The ice stream is about 6 km wide and 85–90 km long, all of which is in an area of surface melting. The base of the ice stream, and of much of the drainage area, is below sea level. Marginal crevasse zones have a width on the order of the width of the ice stream itself. Unique surficial features are ice blisters and lakes; the latter have a sequence of ogive-like features on their floating ice cover which can be used to determine velocity. There is a pinning point near the terminus which may act as a stabilizing influence, possibly playing a role in halting, at least temporarily, a recent retreat of the terminus. Ice-thickness estimates at the terminus lead to a flux which is less than previously assumed by others (e.g. Bindschadler, 1984; Pelto and others, 1989) when estimating Jakobshavns Isbræ’s drainage basin to be nearly in balance. The driving stresses on Jakobshavns Isbræ are an order of magnitude higher than those of the ice streams of West Antarctica. Its crevasse patterns are much less localized. Its relatively unconfined terminus is more comparable to that of relatively unbuttressed ice streams such as Pine Island and Thwaites Glaciers than it is to other West Antarctic ice streams which terminate in large, confined ice shelves. |
format |
Article in Journal/Newspaper |
author |
Echelmeyer, K. Clarke, T. S. Harrison, W.D. |
author_facet |
Echelmeyer, K. Clarke, T. S. Harrison, W.D. |
author_sort |
Echelmeyer, K. |
title |
Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology |
title_short |
Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology |
title_full |
Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology |
title_fullStr |
Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology |
title_full_unstemmed |
Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology |
title_sort |
surficial glaciology of jakobshavns isbræ, west greenland: part i. surface morphology |
publisher |
Cambridge University Press (CUP) |
publishDate |
1991 |
url |
http://dx.doi.org/10.1017/s0022143000005803 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000005803 |
genre |
Antarc* Antarctic Antarctica glacier Greenland Ice Sheet Ice Shelves Journal of Glaciology Pine Island West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica glacier Greenland Ice Sheet Ice Shelves Journal of Glaciology Pine Island West Antarctica |
op_source |
Journal of Glaciology volume 37, issue 127, page 368-382 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000005803 |
container_title |
Journal of Glaciology |
container_volume |
37 |
container_issue |
127 |
container_start_page |
368 |
op_container_end_page |
382 |
_version_ |
1797574019215523840 |