Implementation of a Numerical Scheme Based on the Dual Time Stepping in COSMO LM: Idealized Test Cases

This paper is part of research on the development and testing of a modified version of COSMO LM, that is aimed to assess the feasibility of a time integration technique called Dual Time Stepping (DTS). In a previous paper it was described the implementation of the proposed time integration core with an application for a steady mountain ideal flow. In the present work the DTS scheme has been applied to an unsteady idealized test case, the non-hydrostatic inertia-gravity wave, that involves the evolution of a potential temperature perturbation in a channel. This study on idealized cases will be followed, in future research, by an assessment of the proposed numerical scheme on a realistic test case for Meteorology and Climatology.