FutureProjection of temperature and precipitation changes in the southern coast of Caspian sea

Temperature and precipitation are among the most important climatic elements in the study of climate change due to significant temporal and spatial changes, and the projection of their changes is agreat importance in environmental planning and hazards. Therefore, in this study, future projection of temperature and precipitation changes in the southern cost ofcaspian sea was investigated. For this purpose, the data of CanESM2 model was used under three scenarios (RCP2.6, RCP 4.5 and RCP 8.5) using the SDSM downscaling model the temperature and precipitation changes in three different periods (2021-2050, 2051-2080- and 2081-2100) were examined in relation to the basic period (1989-2018). To calibration and validation the SDSM model, stationary observation data and NCEP data were used, as well as MAE, MSE, RMSE and R2 indicators. The results showed that the SDSM model has the ability to simulate temperature and precipitation changes in the study. Based on the results of the CanESM2 model output, the minimum and maximum temperatures will be increase in all studied periods and each period compared to the previous period, the average amount for the minimum temperature is 2 oC and for the maximum temperature, it will be 2.2 oC  compared to the base period. Most of the temperature changes are related to the western regions of the study area. The projection of precipitation changes also shows that except ofGorgan station in other stations study, the amount of precipitation will decrease in all future periods compared to the base period, the average of which will be during the next period (2021-2100),Will be equal to 3.6%. Most of its changes are related to the central and western areas of the study area. Also, the RCP8.5 scenario showed the most changes in temperature and precipitation.