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, UA-ICON), 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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• Avsarkisov, V. & J. F. Conte, 2023: The Role of Stratified Turbulence in the Cold Summer Mesopause Region. J. Geophys. Res. Atmos. 128,  19: 038322, doi:10.1029/2022jd038322.
• Ghosh, P., M. He, R. Latteck, T. Renkwitz, V. Avsarkisov, M. Zecha & J. L. Chau, 2022: Characteristics of Frequency-Power Spectra in the Troposphere and Lower Stratosphere Over Andøya (Norway) Revealed by MAARSY. J. Geophys. Res. Atmos. 127,  13, doi:10.1029/2021jd036343.
• Heilig, B., C. Stolle, G. Kervalishvili, J. Rauberg, Y. Miyoshi, F. Tsuchiya, A. Kumamoto, Y. Kasahara, M. Shoji, S. Nakamura, M. Kitahara & I. Shinohara, 2022: Relation of the Plasmapause to the Midlatitude Ionospheric Trough, the Sub‐Auroral Temperature Enhancement and the Distribution of Small‐Scale Field Aligned Currents as Observed in the Magnetosphere by THEMIS, RBSP, and Arase, and in the Topside Ionosphere by Swarm. J. Geophys. Res. Space Physics 127,  3, doi:10.1029/2021ja029646.
• Poblet, F. L., J. L. Chau, J. F. Conte, V. Avsarkisov, J. Vierinen & H. Charuvil Asokan, 2022: Horizontal Wavenumber Spectra of Vertical Vorticity and Horizontal Divergence of Mesoscale Dynamics in the Mesosphere and Lower Thermosphere Using Multistatic Specular Meteor Radar Observations. Earth Space Sci. 9,  9: 002201, doi:10.1029/2021ea002201.
• Poblet, F. L., J. Vierinen, V. Avsarkisov, J. F. Conte, H. Charuvil Asokan, C. Jacobi & J. L. Chau, 2023: Horizontal Correlation Functions of Wind Fluctuations in the Mesosphere and Lower Thermosphere. J. Geophys. Res. Atmos. 128,  6, doi:10.1029/2022jd038092.
• Schaefer-Rolffs, U., 2023: A Dynamic Mixed Model for General Circulation Models. Meteorol. Z. 32,  5: 413-429, doi:10.1127/metz/2023/1160.
• Stolle, C., T. A. Siddiqui, L. Schreiter, S. K. Das, I. Rusch, M. Rother & E. Doornbos, 2024: An Empirical Model of the Occurrence Rate of Low Latitude Post-Sunset Plasma Irregularities Derived From CHAMP and Swarm Magnetic Observations. Space Wea. 22,  6: 003809, doi:10.1029/2023sw003809.
• Vierinen, J., F. L. Poblet, J. L. Chau, V. Avsarkisov, H. L. Pécseli, M. Tsutsumi, S. Nozawa, M. G. Johnsen, R. Latteck & N. Gulbrandsen, 2024: Dissipation Rates of Mesospheric Stratified Turbulence From Multistatic Meteor-Radar Observations. Geophys. Res. Lett. 51,  11, doi:10.1029/2023gl105751.