Restoring mass conservation to shallow ice flow models over complex terrain

Numerical simulation of glacier dynamics in mountainous regions using zero-order, shallow ice models is desirable for computational efficiency so as to allow broad coverage. However, these models present several difficulties when applied to complex terrain. One such problem arises where steep terrai...

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Bibliographic Details
Published in:The Cryosphere
Main Authors: A. H. Jarosch, C. G. Schoof, F. S. Anslow
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2013
Subjects:
geo
Online Access:https://doi.org/10.5194/tc-7-229-2013
http://www.the-cryosphere.net/7/229/2013/tc-7-229-2013.pdf
https://doaj.org/article/7239137d86bf40db938cac5a022c5872
Description
Summary:Numerical simulation of glacier dynamics in mountainous regions using zero-order, shallow ice models is desirable for computational efficiency so as to allow broad coverage. However, these models present several difficulties when applied to complex terrain. One such problem arises where steep terrain can spuriously lead to large ice fluxes that remove more mass from a grid cell than it originally contains, leading to mass conservation being violated. This paper describes a vertically integrated, shallow ice model using a second-order flux-limiting spatial discretization scheme that enforces mass conservation. An exact solution to ice flow over a bedrock step is derived for a given mass balance forcing as a benchmark to evaluate the model performance in such a difficult setting. This benchmark should serve as a useful test for modellers interested in simulating glaciers over complex terrain.