Impact of climate change on runoff process in headwater area of the Yellow River

The impact of temperature and precipitation changes on annual and monthly runoff process in headwater area of the Yellow River was analyzed by using WEP-L model.The model was calibrated and verified by the 45 years observed meteorological data obtained from the Tannaihai Hydrological Station.On this basis,the simulation of 8 climate change scenarios was carried out.The results indicate that the increase of atmospheric temperature causes the decrease of annual runoff,the runoff significantly reduced from May to October due to the increase of evaporation but it will increase from November to April of next year because of the melting of snow and the change of infiltration characteristics caused by frozen.The variation of precipitation may directly affect the change of runoff,but the variation rate of runoff is larger than the change rate of precipitation.