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Abstract

Unresolved processes in climate models present a major source of uncertainties in future climate projections. In this talk we will show the first results and introduce a newly founded five year project that aims to re-examine the climate impacts of atmospheric internal gravity waves (GWs) using GW resolving simulations, and to translate this knowledge to the development of modified GW parameterizations in climate models. Within the project, we employ state-of-the-science high-resolution atmospheric datasets and theoretical methods for GW detection and wave-mean flow interaction to revisit and advance our understanding of GW effects on middle atmospheric dynamics, composition and coupling across atmospheric layers. GWs exist on a variety of scales, but typically a significant portion of the GW spectrum remains unresolved in global weather prediction or climate models and the GW impacts need to be parameterized. Our knowledge on GW impacts ranging from regionality of precipitation to the evolution of the ozone layer has been so-far based on their predominantly parameterized effects. Analyzing the resolved GW effects will improve our understanding on the forcing of selected atmospheric phenomena like Sudden Stratospheric Warmings or Brewer-Dobson circulation, but will also put additional constraints on the current GW parameterizations by showing to what extent their effects (and our current understanding) are artificial. This will help us to modify GW parameterization schemes with an ultimate goal of alleviating the uncertainty in future climate projections.