HR: 0800h
AN: C51A-0096 [Abstracts]
TI: A Least Squares Collocation Method for Modeling Ice, Water and Sediment Transport
AU: * Egholm, D L
EM: david@geo.au.dk
AF: Department of Earth Sciences
University of Aarhus, Høegh-Guldbergs Gade 2, Aarhus, DK8000, Denmark
AU: Nielsen, S B
EM: sbn@geo.au.dk
AF: Department of Earth Sciences
University of Aarhus, Høegh-Guldbergs Gade 2, Aarhus, DK8000, Denmark
AU: Pedersen, V K
EM: vivi.pedersen@geo.au.dk
AF: Department of Earth Sciences
University of Aarhus, Høegh-Guldbergs Gade 2, Aarhus, DK8000, Denmark
AB:
We present a new least squares collocation method for computational simulation of ice related flow processes
on a three dimensional topographic surface. The collocation approach is predicated on 1) irregular, cell-based
discretization of the topographic surface, 2) local second-order polynomial approximation of the bed topography
and ice surface, and 3) Runge-Kutta time marching. The ice flow is simulated in 2D planform using a second-
order shallow-ice approximation (SOSIA). Hence, higher order asymptotics, including contributions from
longitudinal stress gradients and ice surface curvatures, are addressed.
The collocation approach leads to a general and highly parallel algorithm based on discrete cell interactions,
which is well suited for simulating also other types of surface flow processes, such as fluvial and hillslope related
sediment transport. The inherent benefit of the method thus relates primarily to the ease with which several types
of earth surface processes may be simulated simultaneously.
Using this new integrated modeling platform, it is our objective to study landform generation by simulating glacial
and fluvio-glacial erosion, sediment transport, and deposition. The dynamics of the ice and of the processes
acting under glaciers must to some degree be manifested by the landforms produced by glaciers, and we wish to
test quantitatively the potential of established sub-glacial dynamical relations for explaining well known large
scale glacial landforms such as U-shaped valleys and cirques.
DE: 0560 Numerical solutions (4255)
DE: 0720 Glaciers
DE: 0726 Ice sheets
SC: Cryosphere [C]
MN: 2007 Fall Meeting