中文摘要：

利用1951~2010年20CR（20th Century Reanalysis Version 2）再分析资料和NOAA海表温度资料研究了赤道印度洋纬向—垂直环流的季节性差异、变化特征及其与Walker环流的关系。本文首先分析了四个季节赤道印度洋上空纬向—垂直环流的结构特征,发现春季和秋季存在严格东西方向上的赤道印度洋纬向—垂直环流。随后,针对春季赤道印度洋纬向—垂直环流变化特征作进一步的分析,研究结果表明,春季纬向—垂直环流的强度及其变率在1951~2010年间持续增强,而该垂直环流的中心位置则表现出明显的年代际变化特征：1981年之前垂直环流的中心位置表现为向西移动,而在1981年后则转为向东移。春季赤道印度洋纬向—垂直环流与Walker环流之间的相关关系同样存在年代际转折,1981年之前两者之间并不存在显著的相关,而在1981年之后,两者之间的关系显著增强。不同年代际时段内赤道印度洋纬向—垂直环流与海温的关系也发生了明显的改变,1981~2010年赤道印度洋纬向—垂直环流主要受到前期和同期太平洋上的ENSO型海温信号的影响,而在此之前该垂直环流主要受到前期和同期赤道东印度洋海温的影响。

英文摘要：

Based on the 20 CR reanalysis dataset and the sea surface temperature（SST） dataset provided by NOAA, seasonal differences and variations of the equatorial Indian Ocean zonal–vertical circulation（EIOZVC） and its correlation with the Walker circulation are investigated. First, structures of the EIOZVC in the four seasons are analyzed,and the results suggest that the EIOZVC in a strictly zonal direction only appears in the spring and autumn. Further studies on variations of the EIOZVC in the spring show that the intensity of the EIOZVC and its variability increased during the period of 1951–2010, while the position of the EIOZVC center experienced a remarkable interdecadal variation： prior to 1981, the EIOZVC center shifted westward; however, it shifted eastward after 1981. There is also a noticeable interdecadal variation in the correlation between the EIOZVC and the Walker circulation in the spring. No high correlation is found between them prior to 1981, whereas the two circulations are found to be highly correlated after 1981. The relationship between the spring EIOZVC and seasonal mean SSTs over the Indian and Pacific Oceans also exhibits different patterns between the two periods, indicating that the EIOZVC is influenced primarily by the Pacific ENSO-like SST signals in the previous winter and the subsequent spring after the year of 1981. Before 1981, however, the EIOZVC was mainly influenced by the equatorial eastern Indian Ocean SSTs.