Analysis of Future Precipitation and Temperature Change and Its Implication on Doroodzan Dam, Iran

Doroodzan dam (Shiraz, Iran) is located in a hot and dry geographical region, and therefore, the effect of climate change on precipitation, temperature, and runoff parameters was studied in the present paper. For that, in the first step, the CanESM2 weather model under the newly RCP2.6, RCP4.5, and RCP8.5 scenarios and microscopic atmospheric model outputs with SDSM model was used to predict precipitation and temperature parameters during 2020–2100. Then simulation of daily discharge of the basin was carried out in the future period with the IHACRES rainfall–runoff model. Comparison of the results with those obtained from climate prediction parameters indicates that the simulation of average temperature parameters has been carried out with high accuracy, but the predicted parameter for precipitation is of less accuracy. This is because the available precipitation data are both non-normal and unconditional. As the results show, the average temperature during 2020–2040, 2041–2069, and 2070–2100, compared to the observation period (1980–2019), would be increased by 0.92, 2.66 and 4.56 °C, respectively. Moreover, there are 9.8%, 26%, and 35.6% decreases in the average precipitation of this basin when measured against the base period.