Turbulence and Diffusion

The impact of micro-scale turbulence on the dynamics can be described in the statistical mean as an effective diffusivity. The statistical behavior of large-scale waves can be described as macro-turbulence. Both concepts need to be considered for a correct treatment of resolved and unresolved scales in numerical simulations.

Methods

For the topic, circulation models with parameterized turbulence were used (KMCM), partly coupled with a chemistry model (CTM-IAP). Theoretical contributions on this subject were devoted to the problem of wave-induced mixing and turbulent closure at different scales.

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• Strelnikov, B., M. Eberhart, M. Friedrich, J. Hedin, M. Khaplanov, G. Baumgarten, B. P. Williams, T. Staszak, H. Asmus, I. Strelnikova, R. Latteck, M. Grygalashvyly, F.-J. Lübken, J. Höffner, R. Wörl, J. Gumbel, S. Löhle, S. Fasoulas, M. Rapp, A. Barjatya, M. J. Taylor & P.-D. Pautet, 2019: Simultaneous in situ measurements of small-scale structures in neutral, plasma, and atomic oxygen densities during the WADIS sounding rocket project. Atmos. Chem. Phys. 19,  17: 11443-11460, doi:10.5194/acp-19-11443-2019.
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