青藏高原及周边地区波动E-P通量的分布与变化特征

为了研究青藏高原及周边地区波动E-P通量的分布与变化特征,利用1965～2010年NCEP/NCAR月平均再分析资料,计算了三维E-P通量,经过分析,得到如下主要结论：（1）对流层波动E-P通量的活动中心位于青藏高原南部.（2）波动E-P通量有着明显的季节变化.其中夏季的强度最大,且夏季与冬季相比,垂直分量正负值中心位置的分布几乎相反.从夏季到冬季,E-P通量垂直分量的正值中心逐渐向东北方向移动.（3）波动E-P通量的年代际变化也比较显著.从20世纪70年代中期到80年代前期,波动E-P通量变化平缓;80年代中期至90年代中期,变化很大,90年代中期达到最强,后又开始逐渐变缓.

Distribution and Variation Characteristics of Three-Dimensional Eliassen-Palm Fluxes of the Waves in the Qinghai-Tibet Plateau and the Surrounding Areas

In order to study the distribution and variation characteristics of the Eliassen-palm （E-P） Flux of waves in Tibet Plateau and the surrounding areas, we use the reanalysis of monthly average data o{ NCEP/NCAR to calculate the E-P Flux in three-dimension. The main conclusions can be drawn as follows, （1） the activity center of the tropo- spheric E-P flux is located in the southern part of the Qinghai-Tibet Plateau. （2） There is a significant seasonality of E-P flux. It is strongest in summer, and the distribution of the positive center and negative center is almost in the op- posite condition in summer and winter. Meanwhile, the positive center of the vertical component is gradually moving to the northeast from summer to winter. （3） The decadal variation of E-P flux is also significant. The E-P flux changed gently from the mid-1970s to the early 1980s, and they changed greatly from the mid-1980s to the mid of 1990s and up to the peak in the mid of 1990s, then began to weaken.