Journal cover Journal topic
The Cryosphere An interactive open-access journal of the European Geosciences Union
The Cryosphere, 11, 541-551, 2017
http://www.the-cryosphere.net/11/541/2017/
doi:10.5194/tc-11-541-2017
© Author(s) 2017. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
15 Feb 2017
Models for polythermal ice sheets and glaciers
Ian J. Hewitt1 and Christian Schoof2 1University of Oxford, Oxford, UK
2University of British Columbia, BC, Canada
Abstract. 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 self-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.

Citation: Hewitt, I. J. and Schoof, C.: Models for polythermal ice sheets and glaciers, The Cryosphere, 11, 541-551, doi:10.5194/tc-11-541-2017, 2017.
Publications Copernicus
Download
Short summary
Many glaciers contain ice both below and at the melting temperature. Predicting the evolution of temperature and water content in such ice masses is important because they exert a strong control on the flow of the ice. We present two new models to calculate these quantities, demonstrate a number of example numerical calculations, and compare the results with existing methods. The novelty of the new methods is the inclusion of gravity-driven water transport within the ice.
Many glaciers contain ice both below and at the melting temperature. Predicting the evolution...
Share