Future projection of climate change in western of Iran based on Representative Concentration Pathways and SDSM Downscaling Model

Future projection of climate change is a great importance in order to be aware of the extent of change and to provide the necessary solutions to adapt to the new conditions. Therefore, in this research, the perspective of temperature and precipitation changes in selected synoptic stations in the west of the country was studied. For this purpose, was used the CanESM2 model data under RCP scenarios (RCP 2.6, RCP 4.5 and RCP 8.5) and SDSM statistical downscaling model. Its monthly and long-term changes were made in two different periods (2046-2065 and 2080- 2099) was compared with the base period (1961-2005). To ensure calibration and validation of the SDSM model, we used MAE, MSE, RMSE, R2 indexes and comparison charts. The results index that this model is suitable for the study area. The results of the model's perspective also showed that during the period of 2046-2065 precipitation in most stations (except for Sarpul Zahab) and more months of the year than the base period decreases. However, during the period (2080-2099) at all stations, precipitation will decrease compared to the base period. In terms of minimum and maximum temperatures, in all periods and in each period, the temperature will increase compared to the base period. Based on the long-term average, expected the precipitation is decrease by 6% and the minimum and maximum temperatures increase respectively 2 and 1.9 Celsius