Assessing future socioeconomic drought events under a changing climate over the Pearl River basin in South China

Abstract

Study regionPearl River basin (PRB) in South China. Study focusThis study aims to assess future socioeconomic drought events under a changing climate over the study region. Variable Infiltration Capacity (VIC) model is used to simulate the streamflow in the PRB during the period of 2020–2099, and 48 projected precipitation datasets from General Circulation Models (GCMs) are selected to drive the VIC model at 0.5° × 0.5° spatial resolution and daily temporal resolution. Then, the minimum in-stream water requirement (MIWR) of the PRB is determined, and trend analysis of the simulated streamflow is conducted. Socioeconomic drought index (SEDI) is used to detect the occurrence of socioeconomic drought event, and further, the impact of the reservoirs in the PRB on drought analysis is evaluated. New hydrological insights for the regionBased on any dataset, nearly one hundred socioeconomic drought events at different severity levels can be identified in the PRB; however, most of them, especially those at severe and extreme levels, can be mitigated through reservoir operation, i.e., reserving at least 40 % of the total manageable storage capacity (TMSC) in the reservoirs. Overall, this study can improve the recognition of future socioeconomic drought events, which is of great value for our society to effectively assess the impacts of climate change and water projects on sustainable water resources utilization in such river basins.