Effect of subglacial volcanism on changes in the West Antarctic Ice Sheet
Rapid changes in the West Antarctic Ice Sheet (WAIS) may affect future global sea-level changes. Alley and Whillans note that 'the water responsible for separating the glacier from its bed is produced by frictional dissipation and geothermal heat,' but assume that changes in geothermal flu...
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ftnasantrs:oai:casi.ntrs.nasa.gov:19930022712 2023-05-15T14:04:19+02:00 Effect of subglacial volcanism on changes in the West Antarctic Ice Sheet Behrendt, John C. Unclassified, Unlimited, Publicly available Jul 1, 1993 http://ntrs.nasa.gov/search.jsp?R=19930022712 unknown http://ntrs.nasa.gov/search.jsp?R=19930022712 Accession ID: 93N31901 No Copyright Other Sources 46 NASA. Goddard Space Flight Center, The First Annual West Antarctic Ice Sheet (WAIS) Science Workshop; p 42 1993 ftnasantrs 2012-02-15T19:56:21Z Rapid changes in the West Antarctic Ice Sheet (WAIS) may affect future global sea-level changes. Alley and Whillans note that 'the water responsible for separating the glacier from its bed is produced by frictional dissipation and geothermal heat,' but assume that changes in geothermal flux would ordinarily be expected to have slower effects than glaciological parameters. I suggest that episodic subglacial volcanism and geothermal heating may have significantly greater effects on the WAIS than is generally appreciated. The WAIS flows through the active, largely asiesmic West Antarctic rift system (WS), which defines the sub-sea-level bed of the glacier. Various lines of evidence summarized in Behrendt et al. (1991) indicate high heat flow and shallow asthenosphere beneath the extended, weak lithosphere underlying the WS and the WAIS. Behrendt and Cooper suggest a possible synergistic relation between Cenozoic tectonism, episodic mountain uplift and volcanism in the West Antarctic rift system, and the waxing and waning of the Antarctic ice sheet beginning about earliest Oligocene time. A few active volcanoes and late-Cenozoic volcanic rocks are exposed throughout the WS along both flanks, and geophysical data suggest their presence beneath the WAIS. No part of the rift system can be considered inactive. I propose that subglacial volcanic eruptions and ice flow across areas of locally (episodically?) high heat flow--including volcanically active areas--should be considered possibly to have a forcing effect on the thermal regime resulting in increased melting at the base of the ice streams. Other/Unknown Material Antarc* Antarctic Ice Sheet NASA Technical Reports Server (NTRS) Antarctic The Antarctic West Antarctic Ice Sheet Whillans ENVELOPE(-64.250,-64.250,-84.450,-84.450) |
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46 Behrendt, John C. Effect of subglacial volcanism on changes in the West Antarctic Ice Sheet |
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description |
Rapid changes in the West Antarctic Ice Sheet (WAIS) may affect future global sea-level changes. Alley and Whillans note that 'the water responsible for separating the glacier from its bed is produced by frictional dissipation and geothermal heat,' but assume that changes in geothermal flux would ordinarily be expected to have slower effects than glaciological parameters. I suggest that episodic subglacial volcanism and geothermal heating may have significantly greater effects on the WAIS than is generally appreciated. The WAIS flows through the active, largely asiesmic West Antarctic rift system (WS), which defines the sub-sea-level bed of the glacier. Various lines of evidence summarized in Behrendt et al. (1991) indicate high heat flow and shallow asthenosphere beneath the extended, weak lithosphere underlying the WS and the WAIS. Behrendt and Cooper suggest a possible synergistic relation between Cenozoic tectonism, episodic mountain uplift and volcanism in the West Antarctic rift system, and the waxing and waning of the Antarctic ice sheet beginning about earliest Oligocene time. A few active volcanoes and late-Cenozoic volcanic rocks are exposed throughout the WS along both flanks, and geophysical data suggest their presence beneath the WAIS. No part of the rift system can be considered inactive. I propose that subglacial volcanic eruptions and ice flow across areas of locally (episodically?) high heat flow--including volcanically active areas--should be considered possibly to have a forcing effect on the thermal regime resulting in increased melting at the base of the ice streams. |
format |
Other/Unknown Material |
author |
Behrendt, John C. |
author_facet |
Behrendt, John C. |
author_sort |
Behrendt, John C. |
title |
Effect of subglacial volcanism on changes in the West Antarctic Ice Sheet |
title_short |
Effect of subglacial volcanism on changes in the West Antarctic Ice Sheet |
title_full |
Effect of subglacial volcanism on changes in the West Antarctic Ice Sheet |
title_fullStr |
Effect of subglacial volcanism on changes in the West Antarctic Ice Sheet |
title_full_unstemmed |
Effect of subglacial volcanism on changes in the West Antarctic Ice Sheet |
title_sort |
effect of subglacial volcanism on changes in the west antarctic ice sheet |
publishDate |
1993 |
url |
http://ntrs.nasa.gov/search.jsp?R=19930022712 |
op_coverage |
Unclassified, Unlimited, Publicly available |
long_lat |
ENVELOPE(-64.250,-64.250,-84.450,-84.450) |
geographic |
Antarctic The Antarctic West Antarctic Ice Sheet Whillans |
geographic_facet |
Antarctic The Antarctic West Antarctic Ice Sheet Whillans |
genre |
Antarc* Antarctic Ice Sheet |
genre_facet |
Antarc* Antarctic Ice Sheet |
op_source |
Other Sources |
op_relation |
http://ntrs.nasa.gov/search.jsp?R=19930022712 Accession ID: 93N31901 |
op_rights |
No Copyright |
_version_ |
1766275352539168768 |