Response of runoff in the source region of the Yellow River to climate warming

The changing characteristics of temperature, precipitation and runoff in the source region of the Yellow River above Tangnag station were analyzed by using hydrological and meteorological data from the past 50 years. The evolving trend of runoff in the future decades is forecasted based on the method of suppositional climate scenarios. The results indicate temperature variation in the region has an evident positive relation with global warming. Precipitation variations are quite intricate in the region at various geographic positions. Runoff in the region has been decreasing continually since the end of the 1980s, because the mean temperature in the region has been rising and precipitation in the main areas of runoff formation in the region has been decreasing. The increased magnitude of runoff may be more than that of precipitation because of the synchronously increasing supply of meltwater from snow, glacier, and frozen soils in future several decades.