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以怒江跨境径流量观测数据、NCEP/NCAR的U场、V场和NOAA的OLR场资料为基础,应用统计分析方法研究了纵向岭谷作用下的怒江跨境径流量变化及其与夏季风的关系.研究表明:怒江跨境径流量主要集中在纵向岭谷区的湿季或雨季(5~10月),其中又以夏季或汛期(6~8月)为最多.怒江的跨境径流量变化从20世纪70年代以来表现出了一种显著增多的时间演变趋势,特别是在20世纪80年代以来的这种增加趋势是十分显著的.夏季怒江跨境径流量与较低层东西风分量的相关性不显著,与较高层东西风分量的相关性显著,与较低层和较高层南北风分量的相关性都是显著的,与OLR场的负相关性也是显著的.同时考虑动力学因子和热力学因子而建立的夏季风指数MI2的年际变化,能在一定程度上较好地反映出纵向岭谷区怒江流域西南季风环流系统的活动和变化,即指数MI2越大,则对应的夏季风环流系统的活动就越强,这时有利于夏季怒江跨境径流量的增加;反之,指数MI2越小,则对应的夏季风环流系统的活动就越弱,这时则不利于夏季怒江跨境径流量的增加.
Based on the data of cross-border runoff in the Nu River and OLR data of UCE, V and NOAA in NCEP / NCAR, statistical analysis was used to study the variation of cross-border runoff in the Nujiang River and its correlation with summer monsoon The results show that the cross-border runoff in the Nujiang River is mainly concentrated in the wet or rainy season (May-October) in the longitudinal ridge-valley region, of which the summer or flood season is the most (June-August) The change in flow rate has shown a markedly increasing trend of time since the 1970s, especially since the 1980s. This trend of cross-border runoff in the Nujiang River is similar to that of the lower-level east wind But the correlation with the components of the east and west winds is significant and the correlation with the north and south wind components of the lower layer and the upper layer is significant and the negative correlation with the OLR field is also significant. The interannual variability of the summer monsoon index MI2 established by the study factor and the thermodynamic factor can reflect the activity and the change of the southwest monsoon circulation system in the Nujiang basin in the Longitudinal Range-Gorge area to a certain extent. The larger the index MI2, Summer monsoon circulation The more active the system is and the more conducive to the increase of cross-border runoff in the Nu River in summer; on the contrary, the smaller the index MI2, the weaker the corresponding activities of the summer monsoon circulation system, Increase in traffic.