SUMMARY
The present study has revealed that North Pacific climate shift of mid 70-ties was pronounced not only in winter mean SST's (as it was described earlier) but in anual and summer means as well. Moreover it appeared that during 50-ties and 60-ties summer anomalies were in general stronger than winter ones. As a result, during this period anomalies of amplitudes of annual cycle of SST's were attributed to anomalies of annual means of the same sign. Starting from early 70-ties winter anomalies became stronger than summer ones. And it resulted in reversed relationship between anomalies of amplitudes of annual cycle and anomalies of annual means. It is found out that such a switch from governing role of summer anomalies in annual cycle formation to that of winter anomalies occurred in 1973, i. e. before North Pacific climate shift.
Undertaken analysis has shown that there is not direct association between climatic changes of amplitudes of semiannual cycle and those of annual and seasonal means of SST's. Anomalies of semiannual cycle can be attributed both to anomalies of annual cycle of the same sign and to ones of opposite sign. Our analysis has not revealed any noticeable climatic changes of phases of annual and semiannual cycles of North Pacific SST's.
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