Uncertainty evaluation of dam inflow under the influence of climate change (study area: Latiyan Dam)

One of the biggest challenges in operating dam reservoirs is predicting incoming flow, which is complicated by the dynamic nature of meteorological parameters. Uncertainty in this area also affects the planning and command curve of the dam and can have a serious impact on it. This study examined the uncertainty of greenhouse gas emission scenarios using five AOGCM models to forecast the inflow to the Latiyan dam, which serves as a source of drinking water. The results indicated a decrease in the inflow volume to the dam, ranging from 34.5 to 66 MCM. The reduction in streamflow volume was analyzed using the results derived from simulating precipitation changes attributed to climate change with the ANN-GWO model. The climate simulation results indicated that the MPI-ESM-MR model exhibited the least significant changes in precipitation. The model GFD-CM3 has recorded the most precipitation changes, directly impacting the incoming flow and future variations. The study of climate behavior showed that the minimum rainfall reduction is about 9 mm per year and the maximum 26 mm per year. The change process has also been affected by snow in the catchment, which has shifted the time of inflow into the reservoir due to the rate of snowmelt.