| Relative importance among observed anomalies in sea surface temperature (SST), surface air temperature and wind speed in determining the anomalous turbulent heat fluxes is assessed through linearizing flux anomalies calculated from individual ship reports contained in Comprehensive Ocean-Atmosphere Data Set (COADS). Over the central basin of the North Pacific, changes in the atmospheric variable associated with basin-scale changes in mid-latitude westerlies, including air temperature and wind speed, are primarily responsible for the generation of local SST variations by changing turbulent heat flux, which supports a conventional view of extratropical air-sea interaction. In the westerern North Pacific along Kuroshio and its extension where ocean dynamics is much important in forming SSTAs, in contrast, SSTAs that have been formed in early winter play the primary role in determining mid- and late-winter turbulent heat flux anomalies, indicative of the SST forcing upon the overlying atmosphere. Specifically, both decadal scale SSTAs in the western Pacific subarctic frontal zone and El Nino related SSTAs south of Japan are found to be engaged actively in such forcing on the atmosphere. The atmospheric response to this forcing appears to include the anomalous storm track activity in the northwestern portion of the North Pacific. Fidelity of these observational results is dis |
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