Theoretical calving rates from glaciers along ice walls grounded in water of variable depths
Abstract Calving has been studied for glaciers ranging from slow polar glaciers that calve on dry land, such as on Deception Island (63.0° S, 60.6° W) in Antarctica, through temperate Alaskan tide-water glaciers, to fast outlet glaciers that float in fiords and calve in deep water, such as Jakobshav...
Published in: | Journal of Glaciology |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1992
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0022143000003695 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000003695 |
id |
crcambridgeupr:10.1017/s0022143000003695 |
---|---|
record_format |
openpolar |
spelling |
crcambridgeupr:10.1017/s0022143000003695 2024-03-03T08:38:07+00:00 Theoretical calving rates from glaciers along ice walls grounded in water of variable depths Hughes, T. 1992 http://dx.doi.org/10.1017/s0022143000003695 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000003695 en eng Cambridge University Press (CUP) Journal of Glaciology volume 38, issue 129, page 282-294 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1992 crcambridgeupr https://doi.org/10.1017/s0022143000003695 2024-02-08T08:37:11Z Abstract Calving has been studied for glaciers ranging from slow polar glaciers that calve on dry land, such as on Deception Island (63.0° S, 60.6° W) in Antarctica, through temperate Alaskan tide-water glaciers, to fast outlet glaciers that float in fiords and calve in deep water, such as Jakobshavns Isbræ (69.2° N, 49.9° W) in Greenland. Calving from grounded ice walls and floating ice shelves is the main ablation mechanism for the Antarctic and Greenland ice sheets, as it was along marine and lacustrine margins of former Pleistocene ice sheets, and is for tide-water and polar glaciers. Yet, the theory of ice calving is underdeveloped because of inherent dangers in obtaining field data to test and constrain calving models. An attempt is made to develop a calving theory for ice walls grounded in water of variable depth, and to relate slab calving from ice walls to tabular calving from ice shelves. A calving law is derived in which calving rates from ice walls are controled by bending creep behind the ice wall, and depend on wall height h , forward bending angle θ crevasse distance c behind the ice wall and depth d of water in front of the ice wall. Reasonable agreement with calving rates reported by Brown and others (1982) for Alaskan tide-water glaciers is obtained when c depends on wall height, wall height above water and water depth. More data are needed to determine which of these dependencies is correct. A calving ratio c/h is introduced to understand the transition from slab calving to tabular calving as water deepens and the calving glacier becomes afloat. Article in Journal/Newspaper Antarc* Antarctic Antarctica Deception Island glacier Greenland Ice Shelves Journal of Glaciology Cambridge University Press Antarctic The Antarctic Greenland Deception Island ENVELOPE(-60.633,-60.633,-62.950,-62.950) Journal of Glaciology 38 129 282 294 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Hughes, T. Theoretical calving rates from glaciers along ice walls grounded in water of variable depths |
topic_facet |
Earth-Surface Processes |
description |
Abstract Calving has been studied for glaciers ranging from slow polar glaciers that calve on dry land, such as on Deception Island (63.0° S, 60.6° W) in Antarctica, through temperate Alaskan tide-water glaciers, to fast outlet glaciers that float in fiords and calve in deep water, such as Jakobshavns Isbræ (69.2° N, 49.9° W) in Greenland. Calving from grounded ice walls and floating ice shelves is the main ablation mechanism for the Antarctic and Greenland ice sheets, as it was along marine and lacustrine margins of former Pleistocene ice sheets, and is for tide-water and polar glaciers. Yet, the theory of ice calving is underdeveloped because of inherent dangers in obtaining field data to test and constrain calving models. An attempt is made to develop a calving theory for ice walls grounded in water of variable depth, and to relate slab calving from ice walls to tabular calving from ice shelves. A calving law is derived in which calving rates from ice walls are controled by bending creep behind the ice wall, and depend on wall height h , forward bending angle θ crevasse distance c behind the ice wall and depth d of water in front of the ice wall. Reasonable agreement with calving rates reported by Brown and others (1982) for Alaskan tide-water glaciers is obtained when c depends on wall height, wall height above water and water depth. More data are needed to determine which of these dependencies is correct. A calving ratio c/h is introduced to understand the transition from slab calving to tabular calving as water deepens and the calving glacier becomes afloat. |
format |
Article in Journal/Newspaper |
author |
Hughes, T. |
author_facet |
Hughes, T. |
author_sort |
Hughes, T. |
title |
Theoretical calving rates from glaciers along ice walls grounded in water of variable depths |
title_short |
Theoretical calving rates from glaciers along ice walls grounded in water of variable depths |
title_full |
Theoretical calving rates from glaciers along ice walls grounded in water of variable depths |
title_fullStr |
Theoretical calving rates from glaciers along ice walls grounded in water of variable depths |
title_full_unstemmed |
Theoretical calving rates from glaciers along ice walls grounded in water of variable depths |
title_sort |
theoretical calving rates from glaciers along ice walls grounded in water of variable depths |
publisher |
Cambridge University Press (CUP) |
publishDate |
1992 |
url |
http://dx.doi.org/10.1017/s0022143000003695 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000003695 |
long_lat |
ENVELOPE(-60.633,-60.633,-62.950,-62.950) |
geographic |
Antarctic The Antarctic Greenland Deception Island |
geographic_facet |
Antarctic The Antarctic Greenland Deception Island |
genre |
Antarc* Antarctic Antarctica Deception Island glacier Greenland Ice Shelves Journal of Glaciology |
genre_facet |
Antarc* Antarctic Antarctica Deception Island glacier Greenland Ice Shelves Journal of Glaciology |
op_source |
Journal of Glaciology volume 38, issue 129, page 282-294 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000003695 |
container_title |
Journal of Glaciology |
container_volume |
38 |
container_issue |
129 |
container_start_page |
282 |
op_container_end_page |
294 |
_version_ |
1792504658882723840 |