Inclusion of a TKE Boundary Layer Parameterization in the Canadian Regional Finite-Element Model

Abstract

The formulation of the regional model recently implemented by the Atmospheric Environment Service of Canada for its operational 48 h NWP forecasts is presented. The emphasis is put on the parameterization of the physical processes, especially those affecting the atmospheric boundary layer. The originality of this model, in addition to the use of 3-D finite elements, of variable meshes in both the horizontal and vertical, and of being non-nested (as previously described by Staniforth and Daley), consists in the treatment of the time-dependent turbulent Kinetic energy (TKE) and the inclusion of the full diurnal cycle. The overall organization of the model calculations it also presented in order to convey a more accurate description of this integrated system. Sample results from the well-known case of the Presidents' Day Cyclone of 1979 and general performance are covered in the last section.