ensitivity analysis to physical parameterizations using a Regional Model.

N. L. PESSACG; S. A. SOLMAN

Buenos Aires

Workshop; Final CLARIS Meeting; 2007

CLARIS-LPB PROJECT

The general objective of this work is to perform and analyse simulations with a Regional Climate Model for climate conditions associated with extreme events. With the intention of finding the optimal configuration of the model, series of sensitivity experiments have been made in terms of domain size, convective and planetary boundary layer (PBL) schemes. The sensitivity of the regional model MM5 was analysed for an anomalously rainy period period (October /November 1986) associated with an extreme event. The experiments showed that the simulated precipitation is depended to the convective schemes, the planetary boundary layer (PBL) schemes and the inclusion of the shallow convection. Grell convective scheme in combination with MRF PBL scheme represents well the precipitation and the low level circulation over La Plata basin. However its experiments fail in simulating the precipitation over Brazil. Kain-Fritsch2 convective scheme (with MRF PBL scheme) does not represent well the precipitation over La Plata basin. Finally, Kain-Fritsch convective scheme, in combination with MRF PBL scheme, is able to reproduce the precipitation in the region.