Comparison of RegCM3 simulated meteorological parameters in Bangladesh: Part II-preliminary result for temperature

Abstract

Simulation of meteorological parameters and comparison of rainfall for Bangladesh is described in part I. This part II describes the comparison of model simulated temperature for Bangladesh. The parameters are simulated by Regional Climate Model version 3 (RegCM3). Temperature simulated by RegCM3 is compared with surface air temperature collected by the Bangladesh Meteorological Department (BMD) at 29 locations throughout the country. RegCM3 is run at 60 km × 60 km horizontal grid resolution in a large domain that covers 65- 117°E and 5-38°N. Grell scheme with Arakawa-Schubert (GAS) and Fritch-Chappell (GFC) assumptions are used in model simulation. GAS run used Lateral Boundary Conditions (LBCs) data for the years of 1995-2000 whereas GFC run used LBC data for 1991, 1994, 1996 and 1999. It is found that a systematic cold bias is existed in simulating temperature for Bangladesh. The model underestimates about 2°C in calculating temperature. In GAS assumption, the model can simulate temperature with about 94% accuracy to the surface air temperature in annual scale. It is found that the GAS option is better than the GFC in simulating temperature in Bangladesh. doi:10.4038/sljp.v8i0.209 Sri Lankan Journal of Physics, Vol. 8 (2007) 11-19