Models for polythermal ice sheets and glaciers
Polythermal ice sheets and glaciers contain both cold ice and temperate ice. We present two new models to describe the temperature and water-content of such ice masses, accounting for the possibility of gravity- and pressure-driven water drainage according to Darcy's law. Both models are based...
Main Authors: | , |
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Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
European Geosciences Union
2017
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Subjects: | |
Online Access: | https://doi.org/10.5194/tc-2016-240 https://ora.ox.ac.uk/objects/uuid:9ffeb79d-18c6-472d-b1d9-c1325e6d42a4 |
Summary: | Polythermal ice sheets and glaciers contain both cold ice and temperate ice. We present two new models to describe the temperature and water-content of such ice masses, accounting for the possibility of gravity- and pressure-driven water drainage according to Darcy's law. Both models are based on the principle of energy conservation; one additionally invokes the theory of viscous compaction to calculate pore water pressure, and the other involves a modification of existing enthalpy gradient methods to include gravity-driven drainage. The models consistently predict the evolution of temperature in cold ice, and of water content in temperate ice. Numerical solutions are described, and a number of illustrative test problems are presented, allowing comparison with existing methods. The suggested models are simple enough to be incorporated in existing ice-sheet models with little modification. |
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