Regulation of the Ural River flow under current and projected climate conditions

The spatially distributed ECOMAG runoff formation model was used to calculate physically based changes in the water regime in the Ural River basin in the XXI century with the use of data of an ensemble of Earth system models and scenarios of anthropogenic impact on the climate system, leading to a considerable decrease in the uncertainty of the existing estimates of the future runoff of the Ural River. Water management calculations for the Ural River were made with the use of the VOLPOW simulation model, which implements the solution of water balance equation by time intervals. The results of variations of the annual and seasonal runoff of the Ural River at different sections were obtained taking into account the effect of the Iriklinskaya Hydropower Station and the Sakmara River under scenarios RCP 4.5 and RCP 8.5 in the nearest future and in the late XXI century. The current potential of runoff regulation in the Ural River by reservoirs was evaluated, and variants of reservoir operation curves for the optimal use of the available water resources are presented. Variants are proposed for adaptation of the rules of runoff regulation by the Iriklinskoe Reservoir and its operation characteristics under expected climate changes in the XXI century, based on water management calculations with the use of long-term series of daily water inflow, determined by the ECOMAG model under scenarios RCP 4.5 and RCP 8.5 relative to the base period 1976–2005.