The joint project of Max Planck Institut for Meteorology Hamburg and Deutscher Wetterdienst to develop a new dynamical core for climate and weather forecasting simulation is presented and outlined. The project has started in the spring of 2002 at MPI Hamburg and is expected to produce a new dynamical core by the end of 2005.

A dynamical kernel based on the discretization of the fully compressible, non-hydrostatic equations is under development. The numerical model will use a icosahedral grid for the horizontal discretization and employ a height based vertical coordinate. Cell centered finite volume discretizations of the continuity equation on either the hexagonal cells or the dual triangular cells are going to be employed.

As a first step towards the full model, conservative, semi-implicit numerical schemes to discretize the shallow water equations the sphere are being developed. Accuracy and benefits of various possible formulations will be analyzed by comparing results obtained on standard test cases.

Preliminary results of numerical simulations will be presented.