Deser, C., and M. L. Blackmon, 1995: On the relationship between tropical and north Pacific sea surface temperature variations. J. Climate, 8, 1677-1680.
Empirical orthogonal function analysis of winter sea surface temperature (SST) anomalies over the Pacific domain (60°N-20°S) reveals an El Niño-Southern Oscillation (ENSO) mode that is linked to the eastern North Pacific, and a North Pacific mode that is linearly independent of ENSO. The North Pacific mode exhibits maximum amplitude and variance explained along ~ 40°N, west of ~ 170°W. SSTs in this region have decreased by ~ 1.5°C from 1950 to 1987. The cooling in winter has been associated with a strengthening of the overlying westerly winds.