A balanced semi-implicit discretization on icosahedral C-grids for the linear shallow water equations on the sphere
نویسنده
چکیده
The linear shallow water equations on the sphere are discretized on a quasi-uniform, geodesic, icosahedral Voronoi-Delaunay grid with a C-grid variable arrangement and semi-implicit time discretization. A finite volume discretization is employed for the continuity equation in conservation law form, using as control volumes either the hexagonal/pentagonal or the dual triangular cells. A geostrophically balanced state is computed as an intermediate step. Results obtained for standard shallow water test cases show that possible spurious geostrophic modes do not affect the quality of the solution and display good inertial gravity wave propagation properties for the linear shallow water equations.
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