Streamflow changes of the Changjiang (Yangtze) River in the recent 60 years: Impacts of the East Asian summer monsoon, ENSO, and human activities
Streamflow changes of the Changjiang (Yangtze) River in the recent 60 years: Impacts of the East Asian summer monsoon, ENSO, and human activities
复制标题
DOI：
10.1016/j.quaint.2013.10.064
复制
发表时间：
2014-06
影响因子：
2.2
通讯作者：
Wen Wei;Yuan‐Pin Chang;Z. Dai
中科院分区：
文献类型：
--
作者：
Wen Wei;Yuan‐Pin Chang;Z. Dai
近几十年来，由于环境因素和相关流域密集的人类活动的耦合，长江径流经历了显着的变化。基于近60年的流量、降水、气温、东亚夏季风（EASM）、厄尔尼诺-南方涛动（ENSO）和水库蓄积等长期数据，讨论了长江沿岸径流变化模式及相关因素。通过经验模态分解对径流观测结果的分析表明，长江沿岸径流由一个趋势和四个内在分量组成。径流趋势分量有明显的下降变化，这主要归因于大坝建设。此外，气候变暖导致融雪量增加，导致更多的水排入上游。水流变化的最终内在分量可以使用经验正交函数分析通过两种模式来表征。主模态表示由于弱 EASM 和弱 ENSO 的耦合而导致的基流周期性振荡。次要模态反映了长江上下游径流变化的差异，与上下游径流变化呈反相位关系。这些差异可能是由弱 EASM 和强 ENSO 造成的。此外，弱的东亚夏季风和厄尔尼诺南方涛动的结合可能导致极端洪水。极端干旱年份可能会受到密集的 EASM 和 ENSO 的显着影响。
Streamflow in the Changjiang River has experienced significant changes in recent decades due to the coupling of environmental factors and intensive anthropogenic activities in associated catchments. Based on a long-term data set, including water discharge, precipitation, temperature, East Asian Summer Monsoon (EASM), El Niño – Southern Oscillation (ENSO), and reservoir volumes in the most recent 60 years, the modes of streamflow changes along the Changjiang and associated factors was discussed. Analysis of streamflow observations by empirical mode decomposition show that streamflow along the Changjiang consist of a trend and four intrinsic components. Trend component in streamflow had obvious downward changes, which could be mainly attributed to dam construction. In addition, increased snowmelt caused by a warming climate led to more water being discharged into the upper reaches. The resultant intrinsic component of streamflow changes can be characterized by two modes using empirical orthogonal function analysis. The main mode represents periodic oscillations in baseflow due to the coupling of a weak EASM and weak ENSO. The secondary mode reflects differences in streamflow changes between the upper and lower reaches of the Changjiang River, which is anti-phased relative to changes in streamflow between the upper and lower reaches. These differences may be caused by a weak EASM and intensive ENSO. Moreover, the combination of a weak EASM and ENSO can lead to extreme flood. Extreme drought years may be significantly impacted by intensive EASM and ENSO.