Cross-spectral analysis is used to examine the dependence of the temporal covariation of sea-surface temperature (SST) anomalies at pairs of spatially separated points in the North Pacific on (1) the time scale of the variations, (2) the relative displacement of the points and (3) their location within the North Pacific basin. Spatial scales con¬sidered here range from 1000 kilometers up to the width of the basin. The study focuses on cross-spectral estimates for the interannual fre¬quency band, 0.125-0.75 yr-1 although estimates for three other bands spanning higher frequencies are also examined.nThe study shows that, on interannual time scales, zonal and merid¬ional coherence length scales are largest along the axes of the major moan North Pacific currents comprising the subtropical and subarctic gyres. The associated phase estimates uniformly indicate a small phase lead for the upstream point.
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