Abstract

The high resolution global climate model LMDZ 4 and 5 and regional climate model RegCM4 has been applied over the South Asia domain to hind-cast the Indian summer monsoon (ISM) circulation. For this study, three-land surface parameterization schemes, the Schématisation d’Echanges Hydrique a l’Interface Biosphère et Atmosphère (SECHIBA) coupled with global climate model LMDZ5, the Biosphere Atmosphere Transfer scheme (BATS) and the Community Land Model (CLM) coupled with regional climate model RegCM4 is used for the study. The regional model RegCM4.0 (BATS and CLM coupled) is driven at the lateral and lower boundaries by NCEP/NCAR reanalysis (NNRP2) data for years of excess (1999) and deficit (1987) rainfall, whereas the global model LMDZ5 (SECHIBA coupled) is driven by initial boundary conditions from European reanalysis datasets and AMIP (Atmospheric model Intercomparison project) and NCEP (National Center for Environmental Prediction) SST, Sea-ice boundary conditions, from 19th Oct 1994 to 19th Oct 1996. The results successfully reproduce the observations due to a realistic reproduction of topographic features. The BATS-RegCM4 simulated precipitation shows better capability to produce ISM features. Also, the LMDZ5-SECHIBA model shows better capability to capture ISM features.

Keywords: BATS; CLM; SECHIBA; RegCM4 LMDZ5; Planetary boundary layer height; Precipitation; Moisture flux