Response of water resources to climate change and its future trend in the source region of the Yangtze River

In this paper, variations of surface water flow and its climatic causes in China are analyzed using hydrological and meteorological observational data, as well as the impact data set (version 2.0) published by the National Climate Center in November 2009. The results indicate that surface water resources showed an increasing trend in the source region of the Yangtze River over the past 51 years, especially after 2004. The trend was very clearly shown, and there were quasi-periods of 9 years and 22 years, where the Tibetan Plateau heating field enhanced the effect, and the plateau monsoon entered a strong period. Precipitation notably increased, and glacier melt water increased due to climate change, all of which are the main climatic causes for increases in water resources in the source region. Based on global climate model prediction, in the SRESA1B climate change scenarios, water resources are likely to increase in this region for the next 20 years.