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Glaicer and Ice Sheet Modeling - governing equations and numerical methods Ìý

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Date and time:Ìý

Tuesday, March 4, 2014 - 10:30am

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Grandview Conference Room, 1320 Grandview Avenue

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I will present an overview of the governing equations of mass, momentum and energy conservation for glacier and ice sheets.Ìý The momentum equation takes the form of a nonlinear Stokes flow problem due to the non-Newtonian ice rheology, and two common approximate forms will also be discussed.Ìý Ice viscosity depends strongly on temperature, necessitating thermo-mechanically coupled models that implement coupled solutions of mass momentum and energy balance equations.Ìý I will also present results from implementation and initial testing of an enthalpy-based thermodynamic module in the Community Ice Sheet Model (within the Community Earth System Model) being developed at Los Alamos National Laboratory and NCAR.Ìý The advantage of the enthalpy-based formulation lies in its ability to handle both cold and temperate ice efficiently by exploiting semi-implicit time-stepping to retain linearity, which is justified by the slow rate of variation of thermal properties.