4-9 September 2022, Bonn, Germany
EMS Annual Meeting Abstracts
Vol. 19, EMS2022-441, 2022, updated on 18 Apr 2023
EMS Annual Meeting 2022
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

What controls the strength of convective circulations in real-case Large-Eddy Simulations during FESSTVaL?

Mirjana Sakradzija1, Noviana Dewani2, Frank Beyrich3, Daniel Klocke4, Ivan Bastak Duran2, Juerg Schmidli2, and Linda Schlemmer5
Mirjana Sakradzija et al.
  • 1Hans-Ertel-Zentrum für Wetterforschung, and Deutscher Wetterdienst, Offenbach, Germany
  • 2Hans-Ertel-Zentrum für Wetterforschung, and Goethe-Universität-Frankfurt, Frankfurt, Germany
  • 3Deutscher Wetterdienst, Meteorologisches Observatorium Lindenberg, Germany
  • 4Max-Planck-Institut für Meteorologie, Hamburg, Germany
  • 5Deutscher Wetterdienst, Offenbach, Germany

Large-Eddy Simulations (LES) are set up to complement the FESSTVaL Field Experiment on sub-mesoscale spatio-temporal variability in Lindenberg using the Icosahedral Nonhydrostatic (ICON) model in a limited-area mode. The LES represent realistic conditions in the area around the observational site and are forced by the ICON-D2 analysis and forecasts. Four nested domains are used of which the innermost one has a horizontal grid resolution of about 75 m. This presentation will focus on the sensitivity of surface turbulent heat fluxes and their spatial variability on soil moisture to explain the discrepancies between the modeled and observed sensible heat flux. In-situ measurements provide the surface heat flux representative of different land cover conditions, crops and forests, while the area-averaged flux is measured along a scintillometer path of several kilometers. Next, a series of experiments will test the sensitivity of the strength of convective circulations on soil moisture. In these experiments, the initial soil moisture is increased, decreased or perturbed in different ways to find what role the variability of soil moisture plays in setting the strength of the convective circulations. The variance of vertical velocity is then compared to the FESSTVaL measurements derived from Doppler Lidar in vertical stare mode to find how realistic the circulations in LES are. This analysis focuses on several "golden days" that include a clear-sky day, three shallow-convective days of which one developed boundary-layer rolls and two precipitating days in June 2021. The complete set of the LES covers the intensive observational period of FESSTVaL from the 7. June to 4. July 2021.

How to cite: Sakradzija, M., Dewani, N., Beyrich, F., Klocke, D., Bastak Duran, I., Schmidli, J., and Schlemmer, L.: What controls the strength of convective circulations in real-case Large-Eddy Simulations during FESSTVaL?, EMS Annual Meeting 2022, Bonn, Germany, 5–9 Sep 2022, EMS2022-441, https://doi.org/10.5194/ems2022-441, 2022.

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