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| Titel |
A confined-unconfined aquifer model for subglacial hydrology |
| VerfasserIn |
Sebastian Beyer, Thomas Kleiner, Angelika Humbert |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250151616
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| Publikation (Nr.) |
 EGU/EGU2017-16353.pdf |
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| Zusammenfassung |
| Modeling the evolution of subglacial channels underneath ice sheets is
an urgent need for ice sheet modellers, as channels affect sliding
velocities and hence ice discharge. Owing to very limited observations
of the subglacial hydraulic system, the development of physical models
is quite restricted. Subglacial hydrology models are currently taking
two different approaches: either modeling the development of a network
of individual channels or modeling an equivalent porous layer where the
channels are not resolved individually but modeled as a diffusive
process, adjusted to reproduce the characteristic of an
efficient system.
Here, we use the latter approach, improving it by using a
confined-unconfined aquifer model (CUAS), that allows the system to run
dry in absence of sufficient water input. This ensures physical values
for the water pressure. Channels are represented by adjusting the permeability and storage of
the system according to projected locations of channels. The evolution
of channel positions is governed by a reduced complexity model that
computes channel growths according to simple rules (weighted
random walks descending the hydraulic potential). As a proof of concept we present the results of the evolution of the hydrological system over time for a simple artificial glacier geometry. |
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