Abstract: Based on the output of the atmospheric general circulation model, the distributed monthly hydrological model was used as a tool to analyze the possible change trend of runoff under future climate scenarios in the upper reaches of the Yangtze River, and then the future change trend of the inflow of Three Gorges Reservoir was analyzed. The HadCM2 model was selected as the future climate scenarios. A large scale distributed monthly water balance model was developed and applied in the upper Yangtze River. The developed model was able to reproduce the historical streamflow record with the average Nash-Sutcliffe efficiency value of 85.34%. Based on the future climate scenarios from the HadCM2 model, using the precipitation and average temperature as the model input, the impacts of climate change on the changes of runoff generation in the upper Yangtze River basin was analyzed. The result shows that, influenced by climate change, the inflow of Three Gorges Reservoir will slightly decrease during the next 30 years, and then tend to increase after 60 years.

Key words: climate change, runoff change, the upper Yangtze River, Three Gorges Reservoir

摘要： 通过对大气环流模型的计算输出结果分析，利用分布式月水文模型分析未来气候情景下长江上游流域径流的可能变化趋势, 进而分析三峡入库径流的变化情况。未来气候情景采用HadCM2模式。建立了分布式月水量平衡模型，模型的模拟精度较高, NASH效率系数达到85.34%。根据长江上游流域未来的气候情景，以降水、平均气温这两个因子作为模型输入，模拟分析未来气候条件下的三峡入库径流变化情况。结果表明：由于气候变化的影响，三峡未来入库径流量在未来30年内呈弱减小趋势，而60年后则呈增大趋势。

关键词: 气候变化, 径流变化, 长江上游流域, 长江三峡