A nonsmooth Newton multigrid method for a hybrid, shallow model of marine ice sheets

Abstract

The time evolution of ice sheets and ice shelves is model by combining a shallow lubrication approximation for shear deformation with the shallow shelf approximation for basal sliding, along with the mass conservation principle. At each time step two p-Laplace problems and one transport problem are solved. Both p-Laplace problems are formulated as minimisation problems. They are approximated by a finite element truncated nonsmooth Newton multigrid method. As an illustration, we compute the steady state shape of an idealized ice sheet/shelf system.