Impact assessment of climate change on dam reservoir: a case study of Shah Wa Arus Dam in Kabul, Afghanistan

ABSTRACT This study was conducted to investigate the effects of climate change on the SWA Dam's reservoir, located in a semi-arid region. In this purpose, the Soil & Water Assessment Tool (SWAT) was used for hydrological modeling, calibration and validation were done using the SWAT Calibration and Uncertainty Program (SWAT-CUP). Future climate data were generated using the Model for Interdisciplinary Research on Climate (MIROC5) from the Coupled Model Intercomparison Project Phase 5 (CMIP5). In the hydrological modeling process, the Representative Concentration Pathway scenarios (RCP4.5 and RCP8.5) were utilized to assess influences throughout 2050-2069 and 2080-2099. So, under the impacts of the RCP4.5 scenario, the temperature is projected to rise by +3.4 °C and +3.8 °C during 2050-2069 and 2080-2099, respectively. However, considering the RCP8.5, it will rise by +4.4 °C and +6.54 °C in the same periods. Additionally, runoff is anticipated to decrease by 71.47% and 67.88% under the RCP4.5, and by 63.03% and 65.2% under the RCP8.5 scenarios during 2050-2069 and 2080-2099 accordingly. Therefore, climate change is expected to cause drought at the SWA dam, leading to future water shortages for the local population. Thus, it is recommended to take action by developing a comprehensive adaptation strategy to ensure sustainable water availability in the region.