Parameterization of Orography-Induced Turbulence in a Mesobeta--Scale Model

Abstract

The possibility of extending existing techniques for turbulence parameterization in the planetary boundary layer to attitude, orography-induced turbulence events is examined. Starting from a well-tested scheme, we show that it is possible to generalize the specification method of the length scales, with no deterioration of the scheme performance in the boundary layer. The new scheme is implemented in a two-dimensional version of a limited-area, numerical model used for the simulation of mesobeta-scale atmospheric flows. Three well-known cases of orographically induced turbulence are studied. The comparison with observations and former studies shows a satisfactory behavior of the new scheme.