Three-dimensional ray-tracing simulations of convective gravity waves

Due to their importance for large-scale circulations and their contribution to the energy and momentum budget of the middle atmosphere, gravity waves have been subject of investigation for many in-situ and satellite measurements. These observations show that the horizontal wavelength of a gravity wave can be as short as a few kilometers, hence, they cannot be directly resolved by General Circulation Models (GCM)s. For this reason, their propagation and interaction with the background atmosphere have to be parametrized. These gravity wave parametrizations play an important role in state-of-the-art GCMs as they contribute to the energy and momentum budget of the middle atmosphere and directly influence the model dynamics. For technical reasons, most gravity wave parametrizations restrict the propagation of gravity waves to the vertical direction. Consequently, modeled distributions of momentum flux and gravity wave drag show remarkable deviations from the three-dimensional propagation as shown in this thesis. The most obvious differences found in the three-dimensional case are the poleward directed meridional drag and the shift of the zonal drag maximum towards higher latitudes in the winter hemisphere. Another simplification of gravity wave parametrizations is the homogeneous and isotropic non-orographic launch distribution, which is unable to resolve single gravity wave sources.