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Titel |
A double continuum hydrological model for glacier applications |
VerfasserIn |
B. Fleurian, O. Gagliardini, T. Zwinger, G. Durand, E. Meur, D. Mair, P. Råback |
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 ; 8, no. 1 ; Nr. 8, no. 1 (2014-01-24), S.137-153 |
Datensatznummer |
250116012
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Publikation (Nr.) |
copernicus.org/tc-8-137-2014.pdf |
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Zusammenfassung |
The flow of glaciers and ice streams is strongly influenced by the
presence of water at the interface between ice and bed. In this
paper, a hydrological model evaluating the subglacial water pressure
is developed with the final aim of estimating the sliding velocities
of glaciers. The global model fully couples the subglacial hydrology
and the ice dynamics through a water-dependent friction law. The
hydrological part of the model follows a double continuum approach
which relies on the use of porous layers to compute water heads in
inefficient and efficient drainage systems. This method has the
advantage of a relatively low computational cost that would allow its
application to large ice bodies such as Greenland or Antarctica
ice streams. The hydrological model has been implemented in the finite
element code Elmer/Ice, which simultaneously computes the ice
flow. Herein, we present an application to the Haut Glacier d'Arolla
for which we have a large number of observations, making it well
suited to the purpose of validating both the hydrology and ice flow
model components. The selection of hydrological, under-determined
parameters from a wide range of values is guided by comparison of the
model results with available glacier observations. Once this selection
has been performed, the coupling between subglacial hydrology and ice
dynamics is undertaken throughout a melt season. Results indicate that
this new modelling approach for subglacial hydrology is able to
reproduce the broad temporal and spatial patterns of the observed
subglacial hydrological system. Furthermore, the coupling with the ice
dynamics shows good agreement with the observed spring speed-up. |
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