气候变化影响下的流域水循环:以长江和黄河典型流域为例

Impact of Climate Change on Hydrological Cycle:Case Studies in the Yangtze River and Yellow River Basins

在对IPCC提供的多种大气环流模式(GCMs)适用性评估的基础上,采用SDSM和ASD统计降尺度模型生成未来气候变化情景,驱动分布式水文模型VIC和SWAT,分别对长江和黄河典型流域进行分布式水文模拟,定量探讨气候变化对流域水循环的影响。结果表明,适应性评估可以有效降低GCMs选择的不确定性,统计降尺度方法能够明显改善全球气候模式降水和气温输出结果。与基准期(1961—1990年)相比,未来时期(2046—2065年和2081—2100年)长江下游太湖流域径流量呈现微弱减少趋势,但汛期东南部径流量增加显著,而黄河上游流域径流量则呈下降趋势。研究结果可为开展我国各大流域适应气候变化研究提供一定的参考依据。

Based upon adaptive assessment of different GCMs recommended by IPCC,the future climate change scenarios were generated by using SDSM and ASD,respectively,and were used to drive the distributed hydrological model VIC and SWAT.The VIC was applied for simulating hydrological processes in the Taihu basin,which is selected as the typical watershed of the Yangtze River basin.The SWAT model was run for simulatimg hydrology in the upper reaches of the Yellow River basin.Then,the impact of climate change on hydrological cycle was quantitatively investigated.Results show that the methods adopted in this study for GCMs adaptive assessment and downscaling could reduce uncertainties effectively.It was detected that a decreasing trend in the upper reaches of the Yellow River basin;a slightly decreasing trend in the lower reaches,of the Yangtze River Basin,but with a significant increasing trend in the southeast of the Taihu basin during flood seasons for the future periods（2046-2065 and 2081-2100）,comparing with the runoff in the baseline period（1961-1990）.These results are of greatly significance for adapting climate change in different river basins for the future.