Six#x2010;hourly surface wind analyses over the North Pacific Ocean covering the 10#x2010;year period 1969#x2013;78 are used to describe synoptic storm activity in terms of parameters that are directly related to the atmospheric forcing of the ocean. The cube of the atmospheric friction velocity, u3*and the curl of the surface wind stress, curl #x3C4;, are used because of their relationship to turbulent vertical mixing and Ekman pumping in the ocean, respectively. In an attempt to isolate synoptic disturbances from mean fields, the time series of surface wind components at each individual grid point are partitioned into #x201C;high#x2010;pass#x201D; (periods shorter than 10 days) and #x201C;low#x2010;pass#x201D; (periods longer than 10 days) components by means of conventional filtering procedures. The two quantities u3*and curl #x3C4; are then calculated from (a) the high#x2010;pass filtered wind components only, (b) a combination of the filtered wind components that include the interaction between the high#x2010; and low#x2010;pass fields, and (c) the unfiltered wind components. These quantities describe the atmospheric forcing of the ocean that is attributable to (a) synoptic storm activity by itself, (b) synoptic storm activity in the presence of the low#x2010;pass (mean) flow, and (c) the total spectrum of wind forcing, respectively.
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