On mass conservation for ice sheets

Evan M. Cummings

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arXiv · 1805.11175

On mass conservation for ice sheets

Evan M. Cummings

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Abstract

A new continuum-mechanical formulation is proposed which encompasses all material processes within and surrounding an ice sheet. Using this formulation, the balance of mass and free-surface relations for ice sheets are derived and elaborated upon. The resulting three-dimensional mass-balance relation is then integrated vertically to produce an ice-sheet quasi-mass-balance relation in the horizontal plane, and is demonstrated to reduce velocity errors in regions with high magnitude surface gradients. An analytic velocity satisfying the corrected mass-balance relation is formulated as a means to verify future numerical ice-sheet models.

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Evan M. Cummings. 2018-05-28. On mass conservation for ice sheets. https://arxiv.org/abs/1805.11175

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