ON AN EFFICIENT NUMERICAL-METHOD FOR MODELING SEA-ICE DYNAMICS

A computationally efficient numerical method for the solution of nonli near sea ice dynamics models employing viscous-plastic rheologies is p resented. The method is based on a semi-implicit decoupling of the x a nd y ice momentum equations into a form having better convergence prop erties than the coupled equations. While this decoupled form also spee ds up solutions employing point relaxation methods, a line successive overrelaxation technique combined with a tridiagonal matrix solver pro cedure was found to converge particularly rapidly. The procedure is al so applicable to the ice dynamics equations in orthogonal curvilinear coordinates which are given in explicit form for the special case of s pherical coordinates.