赤道东太平洋海温与长江下游地区降水异常的相关分析

THE CORRELATION ANALYSIS BETWEEN THE SEA TEMPERATURE ON THE EQUATORIAL EAST PACIFIC AND THE ANOMALOUS RAINFALL IN THE LOWER REACHES OF THE YANGTZE RIVER

本文采用最大熵谱分析方法揭示了赤道东太平洋海温和长江下游地区降水均存在3-4年和准两年的周期性振荡特征。且通过时滞相关分析发现两者均存在显著的相关关系,并以降水滞后海温约4个月的正相关最为明显。在此基础上利用一个多级数字滤波器对两者的逐月距平序列进行了高通、低通和带通滤波,并对两者在不同时间尺度上的滤波分量进行时滞相关分析,结果发现只是在2-4年的时间尺度上两者相关最为密切,并以降水滞后海温4-5月的正相关最为显著。

This paper reveals that the periodic oscillation performs in 3-4 years and quasi-two years between the sea temperature on the equatorial East Pacific and the rainfall in the lower reaches of the Yangtze River, using maximal entropy spectral analysis method. Moreover, it is found that both mentioned above have the obvious correlation passing the time delay correlation analysis. It is most obvious that the sea temperature has the positive correlation with the rainfall delaying four-month. Furthermore, a multiple-stage numerical filter is used for the both departure sequence month by month to conduct high-pass, low-pass and band-pass filter. And it has conducted the time delay correlation analysis for the both at the different time scales.