April and May of 1988 along the central California coast were characterized as a period of strong coastal upwelling produced by moderate to strong northwesterly winds present throughout the period. A product of this upwelling event was the manifestation of southward geostrophic currents which extended to a distance of approximately 50 km from the coast. From 08 to 11 May 1988, hydrographic surveying was conducted within the Monterey Bay. Internal waves, with amplitudes of up to 30 m were present throughout the period and effectively masked the mean signal, implying that averaging is essential to avoid aliasing. The current -- temperature -- depth (CTD) data were averaged to estimate the mean field during this time frame. Acoustic Doppler Current Profiler (ADCP) data, were also averaged. The mean flow field and dynamic topography implied anticyclonic surface flow with cyclonic flow at 200 m depth. ADCP derived mean flows compared favorably with geostrophic mean flow rate in all areas except one, the deep outflow region along the northern wall of the Canyon. Application of ocean models of boundary layer flow of the geostrophic mean field yielded flows similar to those described above. Wind stress experiments indicated that strong wind field may influence surface circulation in the Bay. Interactions between the coastal upwelling geostrophic jet and the Monterey Submarine Canyon is believed to have been a major mechanism responsible for the mean flow.

The diurnal-period fluctuations of winds and surface currents are analyzed for September 1992 in and around Monterey Bay. Wind records are compared for three coastal stations and two mooring sites. Remotely-sensed surface current observations from two CODAR (HF radar) sites are used to explore the ocean's response to diurnal-period forcing. An average diurnal cycle is formed at each wind station and at all CODAR bins. The earliest sea breeze response is seen at the coastal wind stations where morning winds accelerate toward the coastal mountain ranges. A few hours later, the coastal winds accelerate to the southeast down the Salinas Valley. Offshore afternoon winds rotate from their normal alongshore orientation to also become aligned with the valley. The CODAR-derived surface currents respond in less than the two-hour sampling rate to the onset of the diurnal onshore winds. Currents accelerate in the direction of the Salinas Valley. As the day progresses, the more offshore currents rotate clockwise out from under the winds in a possible Ekman or inertial adjustment that continues throughout the night and spreads onshore. In the afternoon, a complicated eddy pattern develops near shore in a possible response to the coastal boundary.

The geomagnetic electrokinetograph (GEK) was used to measure surface currents near the center of Monterey Bay during six separate 24-hour periods from May through July, 1972. An average of 244 current vectors were derived for each cruise. The mean currents from these cruises are all southerly and ranged from 4.1 cm/sec to 20.4 cm/sec. The average of these mean currents is 12.1 cm/sec toward 163T. These values were compared with individual currents derived from dynamic topographies from the same period. Diurnal and semi-diurnal variations of the current were studied after subjecting the data to a Fourier analysis. It was concluded that there must be at least an indirect coupling of the ocean currents with the semi-diurnal tide at the data point. The diurnal component also is important; it may be tidal or inertial, or merely related to the passage of the sun. (Author).

In August of 2006 the Adaptive Sampling and Prediction (ASAP) experiment was conducted near the northern Monterey Bay. Multiple assets including aircraft, autonomous vehicles, moorings, and numerical models were used to gain a better understanding of three-dimensional upwelling centers. Data were collected at two separate mooring locations using Acoustic Doppler Current Profilers (ADCPs) during the experiment. The focus of this thesis is to determine the effects of local wind forcing on the ocean circulation and provide a comparison between the data collected at the mooring locations and numerical predictions for the region. Upwelling and relaxation events are used as the basis for understanding the local wind forcing. Upwelling typically results in equatorward flow while relaxation events typically result in poleward flow. Several different types of analyses were used to determine the effects of the local wind forcing. A visual analysis was performed with stick vector plots and component plots of the rotated time series that compared the wind with the data from the water column. Two methods of cross correlation, component correlations and vector correlations, were exploited as well as a spectral analysis of the wind and ADCP data. Finally the coherence and phase between the wind and currents were examined. Based on the analysis it became evident that the currents were forced by both wind and non-local events such as eddies, meanders, and the large-scale alongshelf pressure gradient. Associated with the ASAP experiment, the Harvard Ocean Prediction System (HOPS), the Regional Ocean Modeling System (ROMS), and the Navy Coastal Ocean Model (NCOM) provided nowcasts that were compared with the mooring data to determine their accuracy and precision. Overall, in the beginning of August the models provided reasonable representations of the flow patterns at the mooring locations. The prediction error increased towards the end of August which was possibly related to data assimilation techniques and more non-local forcing at that time. The military application of this thesis is that accurate current prediction by ocean models will benefit amphibious operations, special warfare operations, and mine warfare in the littoral zone.

A first order description of tidal heights and currents in Monterey Bay is provided. Analysis of sea level records indicate that a mixed, predominantly semidiurnal tide nearly co-oscillates within the bay. Analysis of month-long moored ADCP records obtained in the winter and summer of 1992 reveals that tidal-band currents account for approximately 50 percent of the total current variance in the upper ocean (20-200 m). A relatively strong (7 cm/s) fortnightly tide (MSf) is present in both seasons. Considerable rotation of the semidiurnal ellipse orientations occurs with depth during both seasons. A month- long record of surface current measurements obtained with CODAR, an HF radar system, during September 1992 reveals that the Monterey Submarine Canyon clearly influences the strength and direction of semidiurnal (M2) tidal currents. Good agreement exists between the strength and orientation of ADCP- and CODAR-derived tidal ellipses, with the exception of the constituent K1. Large, spatially uniform K1 surface currents (20-30 cm/s) appear to be the result of diurnal sea breeze forcing.