The Impacts of Climate Change on Regional Surface Water Supply from Reservoir Storage in China

摘要

China' s surface water runoff is highly variable in both time and space. The northern and northeastern Chinese watersheds suffer from water scarcity where the total renewable water resource is not enough to meet demand, while the Southern regions have more than enough water. The entire country has historically suffered from frequent flood and drought disasters. To mitigate the negative impacts of this variability in water resource availability, China has spent billions developing thousands of reservoirs, water diversions from South to North, and other water works projects. In light of the ongoing massive capital investment, it is important to consider the impacts climate change can have on water resources in the country. This paper employs hydrologic modeling to develop storage - yield curves and storage - cost curves for nine major watershed regions in China, calculates the sensitivity of surface water runoff and the storage - yield curves to changes in temperature and precipitation, and applies results from three GCM scenarios to indicate possible changes to the surface water resources in the nine regions, the storage - yield functions, and the cost to maintain current water supply levels. The results of these climate change scenarios are generally favorable for China, although maintaining current water supply levels could still cost China close to 300 billion yuan.