EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

First results of applying the updated two-energies turbulence scheme over complex terrain

Juerg Schmidli1,2, Ivan Bastak Duran3, Julian Quimbayo-Duarte1,2, Mirjana Sakradzija2,4, and Shweta Singh1,2
Juerg Schmidli et al.
  • 1Goethe University, Institut for Atmospheric and Environmental Sciences, Frankfurt am Main, Germany
  • 2Hans Ertel Centre for Weather Research, Offenbach, Germany
  • 3ECMWF, Bonn, Germany
  • 4Deutscher Wetterdienst, Offenbach, Germany

The unified parameterization of turbulence and clouds in the atmospheric boundary layer is one of the challenges in current weather and climate models. The updated two-energy turbulence scheme is able to successfully model both stratocumulus cases and shallow convection without the need of an additional parameterization for non-local fluxes. The update includes the introduction of the entropy potential temperature to distinguish between a shallow convection and a stratocumulus regime. In addition, the two-energy scheme is coupled to a simplified assumed PDF method in order to achieve a more universal representation of the cloudy regimes. The updated turbulence scheme has been tuned based on several idealized cases and is now evaluated for several real cases in the ICON modeling framework. These cases include cloud streets over relatively flat terrain and stable boundary layers including fog over complex terrain. The performance of the updated scheme is comparable to or better than the operational setup, and can be thus used instead of the operational turbulence and shallow convection scheme in ICON.

How to cite: Schmidli, J., Bastak Duran, I., Quimbayo-Duarte, J., Sakradzija, M., and Singh, S.: First results of applying the updated two-energies turbulence scheme over complex terrain, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-8867,, 2023.