Evaluation and projection of the annual maximum streamflow in response to anthropogenic and climatic effects under nonstationary conditions in the Hanjiang River Basin, China

Abstract The flood regimes have been changing due to the climate change and human activities. Evaluating risk under nonstationarity is critical water resource management authorities in disaster reduction. In this study, annual maximum streamflow (AMS) was used analyze frequency Hanjiang River (HJR) Basin. A Generalized Additive Model for Location, Scale Shape (GAMLSS) employed characterize AMS with time, as well climatic anthropogenic factors. Additionally, changes of response future activity are also investigated. Results indicate that behavior can be better described by nonstationary model physically based covariates than time stationary model, implying HJR Basin mainly influenced factors including reservoir, precipitation temperature. temperature projected Statistical Downscaling (SDSM) two scenarios (RCP2.6 RCP4.5) characterized an increasing trend over period 2006–2100. Furthermore, found during 2051–2100, indicating likely increase alone without further hydrological engineering management. results quantified conditions provided information decision-makers address potential risks posed