The Icosahedral non-hydrostatic (ICON) general circulation model developed jointly by the Max Planck Institute for Meteorology (MPI-M) and the German Weather Service (DWD) is being extended upwards up to the lower thermosphere. The model development at the MPI-M focuses on implementing physical processes of importance to the upper atmosphere, while the DWD pursues the extension of the dynamical core involving, among other things, relaxing the shallow water approximation. One of the goals of the development is to study gravity wave processes in the upper atmosphere, including, e.g., gravity wave breaking and energy deposition and diffusion induc ed thereby.

Here, as a first step, we analyze the results of a 10-year AMIP simulation at gravity wave-permitting resolution (R2B6, ~40 km) using the standard ICON with the model top at 83 km and 47 vertical levels, from 50 km upwards being a numerical absorbing layer. In this simulation, both orographic and non-orographic gravity wave parameterizations are used. Gravity wave momentum flux is going to be computed and compared with existing observational studies as well as low and high resolution model simulations with and without gravity wave parameterizations. Comparisons regarding gravity wave momentum flux, in terms of zonal mean distributions, vertical profiles, global winter and summer patterns, and interannual variability are planned. Such analysis is expected to not only shed light on the performance of gravity wave simulation with ICON, but also offer additional insights on potential ways to improve the parameterizations on gravity wave-permitting resolutions.

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*email: guidi.zhou@mpimet.mpg.de
*Preference: Poster