Research on Meteorological Drought Risk Prediction in the Daqing River Basin Based on HADGEM3-RA

Abstract

Climate change is altering the water cycle and increasing drought risks in river basins. However, few studies account for minor droughts, despite their limited environmental impact. This study uses a pooling and exclusion method to remove the effects of minor droughts on the identification of drought events and analyze drought characteristics in the Daqing River Basin (DRB) using the HADGEM3-RA model within an Exposure–Resilience–Vulnerability (ERV) framework. It finds that the drought duration and the number of events are sensitive to pooling and exclusion rates. Drought severity is also sensitive to exclusion rates. Pooling and exclusion lead to fewer but longer and more severe droughts. Future droughts in the DRB are projected to become more severe, with durations averaging up to 7 months and severity increasing from 0.2 to 4.3. Drought peak severity is expected to exceed 1.28, with development and relief periods extending to 0.68 and 0.69 months, respectively. Risk levels in the basin are projected to rise from I to II–IV, with RCP4.5 scenarios showing higher risks than RCP8.5. Mountainous areas will face higher risks compared to plains. Initially, risk factors will increase then decline over time. These findings clarify drought dynamics and risk changes in the DRB under climate change. They can help in developing climate-resilient strategies for disaster reduction in similar basins.