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| Titel |
Tipping temperatures within Subglacial Lake Ellsworth, West Antarctica |
| VerfasserIn |
Malte Thoma, Klaus Grosfeld, Christoph Mayer, Andrew Smith, John Woodward |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250035281
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| Zusammenfassung |
| One of the most remote and undiscovered regions on Earth are subglacial
lakes. More than 275 of these lakes have been identified so far. However,
from most lakes little more is known but the location or the lateral extent.
Their inaccessibility increases the importance of numerical models to
investigate the physical conditions in these environments. During the
Southern Summer 2008/09, the British Antarctic Survey (BAS) performed field
measurements in the Ellsworth Mountains, West Antarctica to survey Subglacial
Lake Ellsworth. We apply a three-dimensional fluid-dynamics lake model on
the geometry of this lake. We present results, indicating that Subglacial
Lake Ellsworth has a unique temperature profile, constituted by the pressure
induced by the ice thickness above as well as the slope of the ice-lake
interface and compare this with the previously modelled Subglacial Lakes
Vostok and Concordia. While Lake Vostok and Lake Concordia show a clear
convective regime, driven by geothermal heating from the lakes bottom for
the overall lake, the ice load on Lake Concordia constitutes a regime where
the line of maximum water density crosses through the lake. This divides
the lake into branches with completely different convective regimes
Sensitivity studies for glacial and probable future scenarios,
where the ice coverage might thin, are discussed. |
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