A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams
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 meltwate...
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2022
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ftdoajarticles:oai:doaj.org/article:4ec6361e9e9d45f3a2172154af1435e5 2023-05-15T16:57:34+02:00 A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams Hsien-Wang Ou 2022-02-01T00:00:00Z https://doi.org/10.1017/jog.2021.110 https://doaj.org/article/4ec6361e9e9d45f3a2172154af1435e5 EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143021001106/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2021.110 0022-1430 1727-5652 https://doaj.org/article/4ec6361e9e9d45f3a2172154af1435e5 Journal of Glaciology, Vol 68, Pp 13-24 (2022) Ice ridge ice streams self-organization stream stagnation subglacial hydrology Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2022 ftdoajarticles https://doi.org/10.1017/jog.2021.110 2023-03-12T01:30:57Z 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 Directory of Open Access Journals: DOAJ Articles Journal of Glaciology 68 267 13 24 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Ice ridge ice streams self-organization stream stagnation subglacial hydrology Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
Ice ridge ice streams self-organization stream stagnation subglacial hydrology Environmental sciences GE1-350 Meteorology. Climatology QC851-999 Hsien-Wang Ou A theory of glacier dynamics and instabilities Part 2: Flatbed ice streams |
topic_facet |
Ice ridge ice streams self-organization stream stagnation subglacial hydrology Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
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 |
Hsien-Wang Ou |
author_facet |
Hsien-Wang Ou |
author_sort |
Hsien-Wang Ou |
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 |
publishDate |
2022 |
url |
https://doi.org/10.1017/jog.2021.110 https://doaj.org/article/4ec6361e9e9d45f3a2172154af1435e5 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology, Vol 68, Pp 13-24 (2022) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143021001106/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2021.110 0022-1430 1727-5652 https://doaj.org/article/4ec6361e9e9d45f3a2172154af1435e5 |
op_doi |
https://doi.org/10.1017/jog.2021.110 |
container_title |
Journal of Glaciology |
container_volume |
68 |
container_issue |
267 |
container_start_page |
13 |
op_container_end_page |
24 |
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1766049134303772672 |