investigation of the effect of climate change on the optimization of dam reservoir operation using dolphin echolocation and gravitational search algorithms (case study: lar dam basin)

Considering the recent human activities and the resulting climate change in optimizing the operation of the dam reservoir, the effects of climate change should be noticed. in this research, in order to extract command curves by dolphin echolocation and gravitational search algorithms, the monthly inflow of the reservoir, the reservoir storage volume, and the downstream demand of the reservoir in case of climate change were calculated .the optimal output values of the reservoir of lar dam (located in larijan, amol city) were determined by the approach of minimizing the total square of the monthly relative deficiencies in supply demand and climate change conditions based on the river flow according to the research, by using hadcm3 and scenarios rcp2.6, rcp4.5, and rcp 8.5, climate change has increased the maximum temperature by 5%, 5.2%, and 6.2%, respectively. it has increased the minimum temperature by 3.5%, 5.6%, 5.17%, and increased precipitation by 8.5%, 9.5%, and 13%, respectively. in addition, the runoff from the intermediate scenarios indicates an increase of 3.3% compared to the base period. moreover, to examine the water allocation policies required downstream, two future and basic conditions are considered. in this study, reservoir efficiency indices in the conditions of (future) climate change and their corresponding values ​​in the base period were compared. the execution results of each of the algorithms show that the execution speed of the de algorithm is much higher than the gsa algorithm, as well as, in the conditions of climate change, the reliability index in the dolphin echolocation and gravity search algorithms has increased.  9.73 and 12.46% vulnerability has decreased by 21.4% and 26.51%, respectively, and reversibility has increased by 18.27% and 17.64%, respectively. the execution results of each of the algorithms show that the execution speed of the de algorithm is much higher than the gsa algorithm. furthermore, in the conditions of climate change, the reliability index in the dolphin echolocation and gravity search algorithms has increased 9.73 and 12.46% vulnerability has decreased by 21.4% and 26.51%, respectively, and reversibility has increased by 18.27% and 17.64%, respectively.