LES of atmospheric boundary layer turbulence - contributions to the improvement of turbulence parameterisation schemes by means of systematic studies of higher order statistical moments and their budgets
Responsible: Rieke Heinze
Project type: Research project funded by the German Weather Service (​DWD-Extramurale Forschung)
Duration: 1/11/2009-31/10/2012

Even in high resolution weather and climate models the turbulence of the atmospheric boundary layer can not be resolved because the underlying processes are on scales much smaller than the grid resolution used in these models. Accordingly, the whole turbulence spectrum has to be parameterised. A lot of these parameterisations are based on the budgets of the second order statistical moments. The budgets are required for example for the estimation of the relative importance of the respective budget terms as well as for the general applicability of the used parameterisation schemes.

In this project all the budgets of the second order moments shall be determined with aid of LES. The focus is on the study of convective boundary layers with clouds to examine the influence of various cloud regimes on the budgets. Therefore, it is planned to simulate a boundary layer with trade-wind cumulus as well as with stratocumulus and under a situation of a cold air outbreak. Further, the influence of inhomogeneities on the various budget equations will be studied.