'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica
Locations of subglacial lakes discovered under fast-moving West Antarctic ice streams tend to be associated with topographic features of the subglacial bed or with areas that have strong variations in basal conditions. Inversion of ice-stream surface velocity indicates that basal conditions under ic...
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ftportlandstate:oai:pdxscholar.library.pdx.edu:geology_fac-1027 2023-05-15T13:58:46+02:00 'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica Sergienko, Olga V. Hulbe, Christina L. 2011-01-01T08:00:00Z application/pdf https://pdxscholar.library.pdx.edu/geology_fac/28 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1027&context=geology_fac unknown PDXScholar https://pdxscholar.library.pdx.edu/geology_fac/28 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1027&context=geology_fac Geology Faculty Publications and Presentations Subglacial lakes -- Antarctica Aquatic ecology -- Antarctica Ice sheets -- Antarctica Geology text 2011 ftportlandstate 2022-01-09T19:24:25Z Locations of subglacial lakes discovered under fast-moving West Antarctic ice streams tend to be associated with topographic features of the subglacial bed or with areas that have strong variations in basal conditions. Inversion of ice-stream surface velocity indicates that basal conditions under ice streams can be highly variable and that there can be widespread regions where basal traction is high. To seek an explanation for why lakes appear to be sited near areas with high basal traction, we use numerical models to simulate ice-stream dynamics, thermodynamics and subglacial water flow. We demonstrate that the ice flow over high basal traction areas produces favourable conditions for the ponding of meltwater. Energy dissipation associated with ice sliding over a region with high basal traction constitutes a water source supplying a lake, and ice-thickness perturbations induced by ice flow over variable traction create local minima in hydraulic potential. Variations in thermodynamic processes caused by such ice flow could be responsible for limiting the horizontal extent of the subglacial lakes. Text Antarc* Antarctic Antarctica Portland State University: PDXScholar Antarctic Siple ENVELOPE(-83.917,-83.917,-75.917,-75.917) Siple Coast ENVELOPE(-155.000,-155.000,-82.000,-82.000) |
institution |
Open Polar |
collection |
Portland State University: PDXScholar |
op_collection_id |
ftportlandstate |
language |
unknown |
topic |
Subglacial lakes -- Antarctica Aquatic ecology -- Antarctica Ice sheets -- Antarctica Geology |
spellingShingle |
Subglacial lakes -- Antarctica Aquatic ecology -- Antarctica Ice sheets -- Antarctica Geology Sergienko, Olga V. Hulbe, Christina L. 'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica |
topic_facet |
Subglacial lakes -- Antarctica Aquatic ecology -- Antarctica Ice sheets -- Antarctica Geology |
description |
Locations of subglacial lakes discovered under fast-moving West Antarctic ice streams tend to be associated with topographic features of the subglacial bed or with areas that have strong variations in basal conditions. Inversion of ice-stream surface velocity indicates that basal conditions under ice streams can be highly variable and that there can be widespread regions where basal traction is high. To seek an explanation for why lakes appear to be sited near areas with high basal traction, we use numerical models to simulate ice-stream dynamics, thermodynamics and subglacial water flow. We demonstrate that the ice flow over high basal traction areas produces favourable conditions for the ponding of meltwater. Energy dissipation associated with ice sliding over a region with high basal traction constitutes a water source supplying a lake, and ice-thickness perturbations induced by ice flow over variable traction create local minima in hydraulic potential. Variations in thermodynamic processes caused by such ice flow could be responsible for limiting the horizontal extent of the subglacial lakes. |
format |
Text |
author |
Sergienko, Olga V. Hulbe, Christina L. |
author_facet |
Sergienko, Olga V. Hulbe, Christina L. |
author_sort |
Sergienko, Olga V. |
title |
'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica |
title_short |
'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica |
title_full |
'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica |
title_fullStr |
'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica |
title_full_unstemmed |
'Sticky spots' and subglacial lakes under ice streams of the Siple Coast, Antarctica |
title_sort |
'sticky spots' and subglacial lakes under ice streams of the siple coast, antarctica |
publisher |
PDXScholar |
publishDate |
2011 |
url |
https://pdxscholar.library.pdx.edu/geology_fac/28 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1027&context=geology_fac |
long_lat |
ENVELOPE(-83.917,-83.917,-75.917,-75.917) ENVELOPE(-155.000,-155.000,-82.000,-82.000) |
geographic |
Antarctic Siple Siple Coast |
geographic_facet |
Antarctic Siple Siple Coast |
genre |
Antarc* Antarctic Antarctica |
genre_facet |
Antarc* Antarctic Antarctica |
op_source |
Geology Faculty Publications and Presentations |
op_relation |
https://pdxscholar.library.pdx.edu/geology_fac/28 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=1027&context=geology_fac |
_version_ |
1766267100197814272 |