Mesoscale wave dynamics throughout the whole atmosphere: Weak and moderately strong stratification

Ulrich Achatz*(1) and Bruno Ribstein(1), Fabian Senf(2), Rupert Klein(3)

(1)Institut fuer Atmosphaere und Umwelt, Goethe-Universitaet Frankfurt, Germany; (2)Leibniz Institute for Tropospheric Research, Leipzig, Germany; (3)Mathematics and Informatics, Freie Universitaet Berlin, Germany

The interaction between mesoscale waves and a synoptic-scale flow is analyzed by multi-scale asymptotic analysis, both in the tropospheric regime of weak stratification and in the stratospheric regime of moderately strong stratification. Classic results for synoptic-scale-flow balances and inertia-gravity wave dynamics are recovered. These are supplemented by explicit expressions for the interaction between mesoscale geostrophic modes, a possibly somewhat overlooked agent of horizontal coupling in the atmosphere, and the synoptic-scale flow. Elastic dynamics plays a significant role in the stratospheric stratification regime, putting corresponding analyses using either Boussinesq or anelastic dynamics on unsafe grounds. Modifications to gravity-wave parameterizations taking these effects into account will be described. Work in progress on the interaction between mesoscale flow and submesoscale waves shall be reported as well.


*Email: achatz@iau.uni-frankfurt.de
*Preference: Invited