Modelling dynamics of glaciers in volcanic craters
General equations of ice dynamics are re-examined, using scale analysis, in order to derive a simplified thermomechanically coupled model for ice flow and heat transfer in ice caps filling volcanic craters. Relatively large aspect ratios between crater depths and diameters, low surface temperatures...
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ftneicon:oai:rour.neicon.ru:rour/129091 2023-05-15T16:22:03+02:00 Modelling dynamics of glaciers in volcanic craters Salamatin A. Murav'yev Y. Shiraiwa T. Matsuoka K. 2000 https://openrepository.ru/article?id=129091 unknown Journal of Glaciology 153 177 46 0022-1430 https://openrepository.ru/article?id=129091 SCOPUS00221430-2000-46-153-SID0033764022 Article 2000 ftneicon 2020-07-21T11:47:06Z General equations of ice dynamics are re-examined, using scale analysis, in order to derive a simplified thermomechanically coupled model for ice flow and heat transfer in ice caps filling volcanic craters. Relatively large aspect ratios between crater depths and diameters, low surface temperatures and intense volcanic heating are the principal characteristics of such craters. The conventional boundary-layer (shallow-ice) approximation is revised to account for these conditions and, in addition, the variable density of the snow, firn and bubbly ice. Large crater depths and intense bottom melting result in longitudinal balance velocities, controlled by both shear and longitudinal stresses, and hence small surface slopes. In such situations ice can be assumed to be linearly viscous. A flowline model of the glacier dynamics is developed using this assumption. Explicit predictive formulas for ice-particle trajectories and age-depth relations, thus obtained, suggest that the age of ice at the bottom of glaciers in volcanic craters on Kamchatka Peninsula, Russia, may reach hundreds or thousands of years. Ice cores from these glaciers represent unique climatic and volcanic archives. Article in Journal/Newspaper glacier Journal of Glaciology Kamchatka Kamchatka Peninsula NORA (National aggregator of open repositories of Russian universities) Kamchatka Peninsula ENVELOPE(160.000,160.000,56.000,56.000) |
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Open Polar |
collection |
NORA (National aggregator of open repositories of Russian universities) |
op_collection_id |
ftneicon |
language |
unknown |
description |
General equations of ice dynamics are re-examined, using scale analysis, in order to derive a simplified thermomechanically coupled model for ice flow and heat transfer in ice caps filling volcanic craters. Relatively large aspect ratios between crater depths and diameters, low surface temperatures and intense volcanic heating are the principal characteristics of such craters. The conventional boundary-layer (shallow-ice) approximation is revised to account for these conditions and, in addition, the variable density of the snow, firn and bubbly ice. Large crater depths and intense bottom melting result in longitudinal balance velocities, controlled by both shear and longitudinal stresses, and hence small surface slopes. In such situations ice can be assumed to be linearly viscous. A flowline model of the glacier dynamics is developed using this assumption. Explicit predictive formulas for ice-particle trajectories and age-depth relations, thus obtained, suggest that the age of ice at the bottom of glaciers in volcanic craters on Kamchatka Peninsula, Russia, may reach hundreds or thousands of years. Ice cores from these glaciers represent unique climatic and volcanic archives. |
format |
Article in Journal/Newspaper |
author |
Salamatin A. Murav'yev Y. Shiraiwa T. Matsuoka K. |
spellingShingle |
Salamatin A. Murav'yev Y. Shiraiwa T. Matsuoka K. Modelling dynamics of glaciers in volcanic craters |
author_facet |
Salamatin A. Murav'yev Y. Shiraiwa T. Matsuoka K. |
author_sort |
Salamatin A. |
title |
Modelling dynamics of glaciers in volcanic craters |
title_short |
Modelling dynamics of glaciers in volcanic craters |
title_full |
Modelling dynamics of glaciers in volcanic craters |
title_fullStr |
Modelling dynamics of glaciers in volcanic craters |
title_full_unstemmed |
Modelling dynamics of glaciers in volcanic craters |
title_sort |
modelling dynamics of glaciers in volcanic craters |
publishDate |
2000 |
url |
https://openrepository.ru/article?id=129091 |
long_lat |
ENVELOPE(160.000,160.000,56.000,56.000) |
geographic |
Kamchatka Peninsula |
geographic_facet |
Kamchatka Peninsula |
genre |
glacier Journal of Glaciology Kamchatka Kamchatka Peninsula |
genre_facet |
glacier Journal of Glaciology Kamchatka Kamchatka Peninsula |
op_source |
SCOPUS00221430-2000-46-153-SID0033764022 |
op_relation |
Journal of Glaciology 153 177 46 0022-1430 https://openrepository.ru/article?id=129091 |
_version_ |
1766010020949917696 |