华盛顿海军天文台天顶筒纬度观测残差与厄尼诺、南方涛动现象的相关性

CORRELATION OF LATITUDE OBSERVATIONAL RESIDUALS OF WASHINGTON PZT AT U.S.NAVAL OBSERVATORY WITH EL-NINO/SOUTHERN OSCILLATION

厄尼诺、南方涛动是地球大气、海洋系统年际变化中最为显著的一种地球动力学运动。现在通常采用Ｔａｈｉｔｉ（１４８°Ｗ，１８°Ｓ）和Ｄａｒｗｉｎ（１３１°Ｅ，１２°Ｓ）两地海平面气压之差这一定量指标来刻划这一种大气、海洋系统的运动，简称为南方涛动指数ＳＯＩ。本文分析华盛顿海军天文台天顶筒１９３２－１９９１年间纬度观测的残差，证实它与ＳＯＩ在年际变化的频段内显著相关：最大相关系数达到０．６－０．７以上，但纬度残差的变化要滞后ＳＯＩ约２年时间。这很可能是一个证据，说明陆地部分的铬垂线变化与大气、海洋系统的大规模运动有关联。

The El-Nino/Southern Oscillation(ENSO)is the most prominent interannual fluctuation in the Earth atmosphere-oceanic system.A single index SOI(Southern Oscillation Index),which is based on the sea level pressure between Tahiti(148°W,18°S)and Darvin(131°E,12°S),has been used to describe the phenomenon related to the ENSO. The paper studies the correlation of the latitude residuals,obtained by the Washington PZT of U.S Naval Observatory during the years of 1932-1991,with the SOI by means of cross correlation. It has been concluded that the latitude residuals at Washington have a significant correlationship in interannual time scale with the SOI:the maximum value of the cross correlation is found to be larger than 0.6-0.7 at the latitude residual phase lag of about 2 years during the studied period. It might be considered as an evidence that the plumb line variations on the earth are related to the large scale movement of the earth atmosphere-oceanic system.