Rainfall and temperature scenario for Bangladesh.

A regional climate model named Providing REgional Climates for Impacts Studies (PRECIS) adapted in gener- ating rainfall scenarios for the SAARC (South Asian Association for Regional Cooperation) region. At first, PRECIS gen- erated rainfall scenario is calibrated with ground-based observed rainfall during baseline period (1961-1990) in Bangla- desh. The regression coefficients obtained through calibration are utilized for validation of PRECIS simulated rainfall dur- ing 2000-2006. PRECIS overestimated rainfall by 12.37%, 1.58%, 10.81%, 4.79 and 13.18% in 2000, 2002, 2003, 2005 and 2006 respectively. It underestimated by 0.64% and 10.84% in 2001 and 2004 respectively. On an average, PRECIS overestimated about 4.47% of surface rainfall. Better performance of PRECIS through validation encourages employing it in rainfall forecasting for Bangladesh. In the second step, rainfall and temperature forecast for Bangladesh is experimen- tally obtained for 2010-2020. This work discloses that the PRECIS simulated rainfall and temperature are not directly use- ful in application purposes. However, after performing calibration, acceptable result is obtained in estimating annual rain- fall in Bangladesh with correlation coefficient is 0.90. Change of rainfall is forecasted from -0.99% (in 2013) to 5.3% (2018) for Bangladesh during 2010 - 2020.