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海面变化记录中隐含着全球和区域变化的重要信息,对这些信号的分离、提取并揭示其变化特征,是深入理解海面变化机制的前提和基础.基于西北太平洋边缘海区10个验潮站1965～2005年月均验潮序列,利用二阶统计量盲源识别(SOBI)方法进行信号分离,结合EMD方法提取海面变化记录中ENSO信号,进而应用小波分析方法探讨了ENSO信号的时空分异特征.结果表明:各站位验潮序列记录了不同类型、不同强度ENSO事件,并表现出显著的时空分异特征,低纬海面对ENSO的响应明显较中高纬强烈;受洋流、地形等要素影响,海面变化对ENSO事件的记录存在型变;海面变化同样揭示了ENSO事件的尺度变化特征,自20世纪80年代以来,坎门以南各站位对ENSO的响应显著增强,其尺度从4年左右逐渐扩展到2～8年,反映了ENSO强度及频率的变化;海面变化记录的强ENSO事件发生前后,在特定尺度上出现相位的反向变化,支持了强ENSO事件的发生可能与尺度间相互耦合与叠加有关的研究结论.
The important information of global and regional changes is implicated in the sea surface change records, and the separation, extraction and revealing of these changes are the preconditions and foundations for understanding the mechanism of sea surface change.Based on the data of 10 tide gauge stations in the northwestern margin of Pacific Ocean ~ 2005 monthly mean tide-tidal wave series, the second-order statistical blind source identification (SOBI) method was used for signal separation, and the ENSO signal was extracted from the sea surface change record combined with EMD method. Then the spatio-temporal differentiation characteristics of ENSO signal were analyzed by wavelet analysis The results show that the ENSO events of different types and intensities are recorded in the tide-register sequence at each station, and show significant spatial and temporal differentiation. The response of ENSO to the sea surface at low latitudes is significantly stronger than that at middle and high latitudes. The sea surface changes also reveal the characteristics of the scale changes of ENSO events. Since the 1980s, the stations south of Kanmen have significantly enhanced the ENSO response, ranging from 4 Gradually expanding to 2-8 years from year to year, reflecting the changes in ENSO intensity and frequency; the phase at a particular scale before and after strong ENSO events recorded in sea level changes To change, to support the occurrence of strong ENSO events may be related research conclusions and superimposed with the mutual coupling between scales.