Assessing the climate change effects on Standardized Precipitation Evapotranspiration Index (SPEI), case study: Latian dam

Studying climate change and its effect on the intensity and frequency of drought can help the proper use of water resources and adaptation to the destructive effects of the drought phenomenon in the future decades. In recent decades, rising global temperatures have disturbed the planetchr('39')s climate balance and caused widespread climate change in most parts of the world. This research tries to assess climate change in 2021-2050 and its impact on drought in the Latian dam. For this purpose, after assessing the efficiency of the SDSM model in simulation of the base period (1992-2019), the downscaling output of the HadGEM model under RCP4.5, and RCP8.5 scenarios was performed to estimate maximum and minimum temperature and precipitation based on Standardized Precipitation Evapotranspiration Index. The outcomes show an increase of 0.85 to 1.54°C in the average monthly temperature under the RCP8.5 scenario and an increase of 0.25 to 1.45°C under the RCP4.5 scenario. Furthermore, the results show a decrease of 31 to 100 mm in average annual precipitation. The highest decrease in precipitation is in February. Also, the annual analysis of the SPEI showed that 65% of the years are normal, therefore, the Latian dam will not face an increase in the frequency of drought in the period 2021-2050, but it is expected that precipitation events mostly will occur in the warm season.