The circulation over the shelf and upper slope off northem Califomia, between 38øN and 42øN, was observed using moored current and temperature recorders deployed as part of the Northern California Coastal Circulation Study (NCCCS), from March 1987 through October 1989. The results of this study provide a larger-scale view of the wind-driven circulation than that described through the 1981-1982 Coastal Ocean Dynamics Experiment (CODE), particularly with regard to alongshore and temporal variations. From an improved description of the frequency structure of wind and current, a very low frequency (VLF) signal is identified in the observed currents at frequencies below those typical of wind forcing. The majority of this VLF variance appears to be accounted for by persistent flow events associated with the presence of mesoscale circulation in the adjacent ocean. The longer duration of the NCCCS also allows an improved description of the seasonality of flow regimes off northern California. Three oceanic seasons are identified: an upwelling season (April-July), a relaxation season (August-November), and a storm season (December-March). Alongshore variations in the strength of upwelling, in the strength of the alongshore flow, both near-surface and undercurrent, and in water temperature not only are a function of latitude, as is the wind, but they also Correspond to location relative to promontories, notably Cape Mendocino. Immediately south of Cape Mendocino, the near-surface flow exhibits an equatorward minimum and a temperature minimum, whereas the undercurrent exhibits a poleward maximum. Conversely, at the moorings immediately north of the cape, temperatures are a maximum and the undercurrent exhibits a minimum. The maximum in near-surface temperature relates to a minimum in upwelling; no significant correlation was found between local wind and current immediately north of Cape Mendocino. This upwelling minimum and the upwelling maximum south of the cape were also observed as persistent sea surface temperature patterns in satellite imagery. Point Reyes and PointArena, was the site where an intensive observational program, the Coastal Ocean Dynamics Experiment (CODE), was conducted to investigate the response of the coastal ocean to strong wind forcing [Lentz, 1991]. CODE was embedded in a larger scale but less intensively sampled component, dubbed SuperCODE, which included observations between Point Conception and the U.S.-Canadian border [Denbo and Allen, 1987; Lentz, 1991].The northern California coast is known as an area where strong winds directly affect the circulation over the continental shelf. In particular, this region is known as the location of maximum equatorward wind stress over the California Current system during spring and summer [Nelson, 1977;Halliwell and Allen, 1987].Halliwell and Allen [ 1987] studied the statistical properties of the coastal wind field along the west coast of the United States from summer 1981 through summer 1982, using both observed and modeled wind fields. Summer winds were sh...

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A numerical model is used to analyze currents measured on the continental shelf near the shore of New Jersey. The model neglects longshore variations of current and all variations of density, but includes inertial accelerations and a nonlinear eddy viscosity. Local wind stress, sea level changes, and a constant longshore pressure gradient are the forcing terms. The model successfully reproduces most of the current variance; however, the predicted currents do not exhibit the dominant 4‐hour response time of the observed currents, and the model sometimes misses energetic current events. These differences are ascribed to three‐dimensional setup effects elsewhere in the New York Bight.