夏季风等环流因子对黄河中游径流量周期变化的影响

基于黄河中游4个水文站1919~2010年还原的天然径流量、1873~2011年的夏季风强度指数、北大西洋涛动指数（NAO）和西太平洋副高指数等资料,利用Morlet小波方法分析了黄河中游河口镇-龙门区间（简称河龙区间）,龙门-三门峡区间（简称龙三区间）和三门峡-花园口区间（简称三花区间）径流量的周期变化,并探索了夏季风、中纬度西风与西太平洋副高等环流因子对黄河中游3个区间径流量周期性变化的影响。研究发现,黄河中游3个区间径流量的变化对夏季风、中纬度西风和西太平洋副高存在差异性响应,季风对于黄河中游的径流量不仅在时间上具有趋势性的影响,更为重要的是存在周期性的控制作用,在80 a长周期上对于整个黄河中游都有控制作用,但影响黄河中游降水-径流过程的不仅仅是夏季风,相关统计结果表明还受到西风带和西太平洋副高周期的影响。3个区间都存在一个中等尺度(25 a)的周期,这个周期在夏季风上没有得到体现,河龙区间和龙三区间的25 a周期是受西风带影响所致,而三花区间的中尺度25 a周期是西太平洋副高指数的强度和西界的作用所致。

Effects of Summer Monsoon and Other Atmospheric Circulation Factors on Periodicities of Runoff in the Middle Huanghe River During 1919-2010

The Morlet wavelet method was adopted to analyze the periodicities of runoff in three regions (Hekouzhen-Longmen, Longmen-Sanmenxia and Sanmenxia-Huayuankou), and to explore its effects on summer monsoon, Westlies and West Pacific Subtropical High (WPSH) on the changes of runoff. Data collected are cumulative natural runoff of four hydrology stations in the middle Huanghe River, annual summer monsoon index, North Atlantic Oscillation, and strength and west boundary of WPSH. Analysis results indicate that the weaken of summer monsoon intensity leads to decreasing trend of runoff in Hekouzhen-Longmen. More importantly, summer monsoon has periodic change, and it’s the mainly reason to periodic vibrations of runoff. Besides, runoff indicate a 80 year period, and it is coincident with 80 year period of summer monsoon. The periodicities of runoff are in fluenced by both summer monsoon and westerly and WPSH. Additionly, runoffs in all these three regions have a medium scale periodicity with 25 year cycle, except the summer monsoon. The 25 year periodicity of runoff in Hekouzhen-Longmen region and Longmen-Sanmenxia region is caused by Westerlies, while the periodicity of runoff in Sanmenxia-Huayuankou region is caused by the intensity and west boundary of the WPSH. The study has theoretical and practical significance for the prediction of water resources in the Huanghe River Basin in the future.