Multi-scale modeling of the urban meteorology: Integration of a new canopy model in the WRF model

Urban parametrizations have been recently developed and integrated in mesoscale meteorological models for a better reproduction of urban heat islands and to compute building energy consumption. The objective of the present study is to evaluate the value of the use of a module able to produce highly resolved vertical profiles of these variables. For this purpose, the Canopy Interface Model (CIM) was integrated as an additional urban physics option in the Weather Research and Forecasting model. The coupling method is here detailed and its evaluation is done using a reference run based on a fine resolution WRF simulation. In order to keep both the CIM and the mesoscale model coherent, an additional term is added to the calculation of the CIM. Finally, the BUBBLE dataset is used to validate the simulation of the profiles from CIM. It is demonstrated that the proposed coupling improves the simulations of the variables in an urban grid and that the WRF + CIM + BEP-BEM system can provide highly resolved vertical profiles while at the same time improving significantly computational time. The data from these preliminary results are very promising as it provides the foundation for the CIM to act as an interface between mesoscale and microscale models.