A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams
Abstract In Part 1, we have considered the dynamics of topographically confined glaciers, which may undergo surge cycles when the bed becomes temperate. In this Part 2, we consider the ice discharge over a flatbed, which would self-organize into alternating stream/ridge pairs of wet/frozen beds. The...
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crcambridgeupr:10.1017/jog.2021.110 2024-03-03T08:45:58+00:00 A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams Ou, Hsien-Wang 2021 http://dx.doi.org/10.1017/jog.2021.110 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021001106 en eng Cambridge University Press (CUP) https://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 68, issue 267, page 13-24 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 2021 crcambridgeupr https://doi.org/10.1017/jog.2021.110 2024-02-08T08:45:12Z Abstract In Part 1, we have considered the dynamics of topographically confined glaciers, which may undergo surge cycles when the bed becomes temperate. In this Part 2, we consider the ice discharge over a flatbed, which would self-organize into alternating stream/ridge pairs of wet/frozen beds. The meltwater drainage, no longer curbed by the bed trough, would counter the conductive cooling to render a minimum bed strength at some intermediate width, toward which the stream would evolve over centennial timescale. At this stationary state, the stream width is roughly twice the geometric mean of the stream height and length, which is commensurate with its observed width. Over a flatbed, streams invariably interact, and we deduce that the neighboring ones would exhibit compensating cycles of maximum velocity and stagnation over the centennial timescale. This deduction is consistent with observed time variation of Ross ice streams B and C (ISB/C), which is thus a manifestation of the natural cycle. Moreover, the model uncovers an overlooked mechanism of the ISC stagnation: as ISB widens following its reactivation, it narrows ISC to augment the loss of the meltwater, leading to its stagnation. This stagnation is preceded by ice thickening hence opposite to the thinning-induced surge termination. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Journal of Glaciology 1 12 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
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Earth-Surface Processes Ou, Hsien-Wang A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams |
topic_facet |
Earth-Surface Processes |
description |
Abstract In Part 1, we have considered the dynamics of topographically confined glaciers, which may undergo surge cycles when the bed becomes temperate. In this Part 2, we consider the ice discharge over a flatbed, which would self-organize into alternating stream/ridge pairs of wet/frozen beds. The meltwater drainage, no longer curbed by the bed trough, would counter the conductive cooling to render a minimum bed strength at some intermediate width, toward which the stream would evolve over centennial timescale. At this stationary state, the stream width is roughly twice the geometric mean of the stream height and length, which is commensurate with its observed width. Over a flatbed, streams invariably interact, and we deduce that the neighboring ones would exhibit compensating cycles of maximum velocity and stagnation over the centennial timescale. This deduction is consistent with observed time variation of Ross ice streams B and C (ISB/C), which is thus a manifestation of the natural cycle. Moreover, the model uncovers an overlooked mechanism of the ISC stagnation: as ISB widens following its reactivation, it narrows ISC to augment the loss of the meltwater, leading to its stagnation. This stagnation is preceded by ice thickening hence opposite to the thinning-induced surge termination. |
format |
Article in Journal/Newspaper |
author |
Ou, Hsien-Wang |
author_facet |
Ou, Hsien-Wang |
author_sort |
Ou, Hsien-Wang |
title |
A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams |
title_short |
A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams |
title_full |
A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams |
title_fullStr |
A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams |
title_full_unstemmed |
A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams |
title_sort |
theory of glacier dynamics and instabilities part 2: flatbed ice streams |
publisher |
Cambridge University Press (CUP) |
publishDate |
2021 |
url |
http://dx.doi.org/10.1017/jog.2021.110 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021001106 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 68, issue 267, page 13-24 ISSN 0022-1430 1727-5652 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2021.110 |
container_title |
Journal of Glaciology |
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1 |
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12 |
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