Towards a physical model of Antarctic sea ice microstructure including biogeochemical processes using the extended Theory of Porous Media

Abstract

AbstractPredictive numerical climate models include an ocean modeling system as an important module, which comprises the components of ocean and sea ice physics as well as the coupled biogeochemical processes occuring in the ocean and sea ice, respectively. Whereas large‐scale, physical sea ice models are well represented, a new thrust for climate modeling is to include the sea ice biogeochemistry (BGC) as a strong influencing factor. For that reason, a demanding challenge is to develop a numerical model for the sea ice microstructure, which considers all relevant physical parts, like the evolution of salinity, thermodynamic properties and mechanical deformation, as well as the biological and chemical conversion processes. The model should be able to quantify phytoplankton biomass, nutrient sources and utilization as well as carbon content and export in connection to the underlying physical and biogeochemical driven mechanisms. A thermodynamically consistent derived continuum mechanical model is developed and prepared by means of a standard GALERKIN procedure to be implemented and solved with the finite element method (FEM). The governing equations and constitutive relations are set up in the framework of the homogenization approach of the extended Theory of Porous Media (eTPM).