A stabilized finite element method for calculating balance velocities in ice sheets

We present a numerical method for calculating vertically averaged velocity fields using a mass conservation approach, commonly known as balance velocities. This allows for an unstructured grid, is not dependent on a heuristic flow routing algorithm, and is both parallelizable and efficient. We apply...

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Bibliographic Details
Published in:Geoscientific Model Development
Main Authors: Brinkerhoff, D., Johnson, J.
Format: Text
Language:English
Published: 2018
Subjects:
Online Access:https://doi.org/10.5194/gmd-8-1275-2015
https://gmd.copernicus.org/articles/8/1275/2015/
Description
Summary:We present a numerical method for calculating vertically averaged velocity fields using a mass conservation approach, commonly known as balance velocities. This allows for an unstructured grid, is not dependent on a heuristic flow routing algorithm, and is both parallelizable and efficient. We apply the method to calculate depth-averaged velocities of the Greenland Ice Sheet, and find that the method produces grid-independent velocity fields for a sufficient parameterization of horizontal plane stresses on flow directions. We show that balance velocity can be used as the forward model for a constrained optimization problem that can be used to fill gaps and smooth strong gradients in InSAR velocity fields.