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| Titel |
Potential subglacial lake locations and meltwater drainage pathways beneath the Antarctic and Greenland ice sheets |
| VerfasserIn |
S. J. Livingstone, C. D. Clark, J. Woodward, J. Kingslake |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1994-0416
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| Digitales Dokument |
URL |
| Erschienen |
In: The Cryosphere ; 7, no. 6 ; Nr. 7, no. 6 (2013-11-11), S.1721-1740 |
| Datensatznummer |
250085179
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| Publikation (Nr.) |
 copernicus.org/tc-7-1721-2013.pdf |
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| Zusammenfassung |
| We use the Shreve hydraulic potential equation as a simplified approach to
investigate potential subglacial lake locations and meltwater drainage
pathways beneath the Antarctic and Greenland ice sheets. We validate the
method by demonstrating its ability to recall the locations of >60% of
the known subglacial lakes beneath the Antarctic Ice Sheet. This is despite
uncertainty in the ice-sheet bed elevation and our simplified modelling
approach. However, we predict many more lakes than are observed. Hence we
suggest that thousands of subglacial lakes remain to be found. Applying our
technique to the Greenland Ice Sheet, where very few subglacial lakes have so
far been observed, recalls 1607 potential lake locations, covering 1.2%
of the bed. Our results will therefore provide suitable targets for
geophysical surveys aimed at identifying lakes beneath Greenland. We also
apply the technique to modelled past ice-sheet configurations and find that
during deglaciation both ice sheets likely had more subglacial lakes at their
beds. These lakes, inherited from past ice-sheet configurations, would not
form under current surface conditions, but are able to persist, suggesting a
retreating ice-sheet will have many more subglacial lakes than advancing
ones. We also investigate subglacial drainage pathways of the present-day and
former Greenland and Antarctic ice sheets. Key sectors of the ice sheets,
such as the Siple Coast (Antarctica) and NE Greenland Ice Stream system, are
suggested to have been susceptible to subglacial drainage switching. We
discuss how our results impact our understanding of meltwater drainage, basal
lubrication and ice-stream formation. |
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