Explosive Growth of Shear-Heating Instabilities in the Down-Slope Creep of Ice Sheets
Abstract The time-scale for the onset of the explosive growth of a finite-amplitude shear-heating instability in the down-slope creep of a thick ice sheet is determined by integrating the equation for the temporal evolution of the temperature-depth profile subsequent to a sudden change in ice thickn...
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Cambridge University Press (CUP)
1986
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Online Access: | http://dx.doi.org/10.1017/s0022143000011977 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000011977 |
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crcambridgeupr:10.1017/s0022143000011977 2024-03-03T08:45:25+00:00 Explosive Growth of Shear-Heating Instabilities in the Down-Slope Creep of Ice Sheets Yuen, David A. Saari, Marc R. Schubert, Gerald 1986 http://dx.doi.org/10.1017/s0022143000011977 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000011977 en eng Cambridge University Press (CUP) Journal of Glaciology volume 32, issue 112, page 314-320 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 1986 crcambridgeupr https://doi.org/10.1017/s0022143000011977 2024-02-08T08:32:56Z Abstract The time-scale for the onset of the explosive growth of a finite-amplitude shear-heating instability in the down-slope creep of a thick ice sheet is determined by integrating the equation for the temporal evolution of the temperature-depth profile subsequent to a sudden change in ice thickness. All instabilities eventually grow explosively after a prolonged period of simmering or relatively slow monotonic growth. Though times for explosive growth depend on initial and final ice thicknesses, surface temperature, accumulation rate, basal heat flux, and ice rheological parameters, the explosion times are extremely sensitive to the activation energy and the pre-exponential constant of the ice-creep law. Sudden increases in ice-sheet thickness of 1–2 km due to a rapid climatic deterioration can lead to explosive instability and melting of the basal shear layer in only thousands of years if ice-creep activation energies are lower than about 60 kJ mol -1 . Article in Journal/Newspaper Ice Sheet Journal of Glaciology Cambridge University Press Journal of Glaciology 32 112 314 320 |
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Open Polar |
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Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Yuen, David A. Saari, Marc R. Schubert, Gerald Explosive Growth of Shear-Heating Instabilities in the Down-Slope Creep of Ice Sheets |
topic_facet |
Earth-Surface Processes |
description |
Abstract The time-scale for the onset of the explosive growth of a finite-amplitude shear-heating instability in the down-slope creep of a thick ice sheet is determined by integrating the equation for the temporal evolution of the temperature-depth profile subsequent to a sudden change in ice thickness. All instabilities eventually grow explosively after a prolonged period of simmering or relatively slow monotonic growth. Though times for explosive growth depend on initial and final ice thicknesses, surface temperature, accumulation rate, basal heat flux, and ice rheological parameters, the explosion times are extremely sensitive to the activation energy and the pre-exponential constant of the ice-creep law. Sudden increases in ice-sheet thickness of 1–2 km due to a rapid climatic deterioration can lead to explosive instability and melting of the basal shear layer in only thousands of years if ice-creep activation energies are lower than about 60 kJ mol -1 . |
format |
Article in Journal/Newspaper |
author |
Yuen, David A. Saari, Marc R. Schubert, Gerald |
author_facet |
Yuen, David A. Saari, Marc R. Schubert, Gerald |
author_sort |
Yuen, David A. |
title |
Explosive Growth of Shear-Heating Instabilities in the Down-Slope Creep of Ice Sheets |
title_short |
Explosive Growth of Shear-Heating Instabilities in the Down-Slope Creep of Ice Sheets |
title_full |
Explosive Growth of Shear-Heating Instabilities in the Down-Slope Creep of Ice Sheets |
title_fullStr |
Explosive Growth of Shear-Heating Instabilities in the Down-Slope Creep of Ice Sheets |
title_full_unstemmed |
Explosive Growth of Shear-Heating Instabilities in the Down-Slope Creep of Ice Sheets |
title_sort |
explosive growth of shear-heating instabilities in the down-slope creep of ice sheets |
publisher |
Cambridge University Press (CUP) |
publishDate |
1986 |
url |
http://dx.doi.org/10.1017/s0022143000011977 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000011977 |
genre |
Ice Sheet Journal of Glaciology |
genre_facet |
Ice Sheet Journal of Glaciology |
op_source |
Journal of Glaciology volume 32, issue 112, page 314-320 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000011977 |
container_title |
Journal of Glaciology |
container_volume |
32 |
container_issue |
112 |
container_start_page |
314 |
op_container_end_page |
320 |
_version_ |
1792500965889277952 |