Response Strategies to Socio-Economic Drought: An Evaluation of Drought Resistance Capacity from a Reservoir Operation Perspective

Inadequate water supply during droughts, leading to socio-economic drought, has become a global issue. In this context, the drought resistance and disaster mitigation capabilities of reservoirs play a crucial role during drought events. Taking the downstream Yellow River Basin (DYRB) as the study area, this research analyzes the evolution and characteristics of socio-economic drought in the region from 1956 to 2016 at different time scales (3 months, 6 months, 9 months, and 12 months). The copula function is used to calculate the joint recurrence period of socio-economic drought in the downstream area. In addition, this study constructs a reservoir optimization operation model to explore the drought resistance capabilities of water supply strategies in response to downstream socio-economic droughts. The results show that the indices across the four time scales indicate that the DYRB faced the most severe socio-economic drought from the 1990s to the early 21st century, with long durations and widespread impacts. Compared with conventional scheduling methods, water supply restriction strategies can cope with more severe socio-economic droughts. However, the maximum drought resistance capacity corresponding to its recurrence period still cannot cope with the socio-economic droughts of the early 21st century. Therefore, the implementation of basin-wide unified water planning is of great importance to improve drought resistance capacity.