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Sixth Conference on Coastal Atmospheric and Oceanic Prediction and Processes The ICON model, a high-resolution, dataassimilating, model of the Monterey Bay area, was initially designed for studying mesoscale features such as eddies and upwelling filaments. Tidal forcing is now being implemented into this model to facilitate short-term particle-tracking studies, and to move towards a real-time operational forecast model.

The article of record as published may be found at: http://dx.doi.org/10.1029/2004GL019718 Turbidity currents are thought to be the main mechanism to move ~ 500,000m3 of sediments annually from the head of the Monterey Submarine Canyon, to the deep-sea fan. Indirect evidence has shown frequent occurrences of such turbidity currents in the canyon, but the dynamic properties of the turbidity currents such as maximum speed, duration and dimensions are still unknown. Here we present the first-ever in-situ measurements of velocity profiles of four turbidity currents whose maximum along-canyon velocity reached 190cm/s. Two turbidity currents coincided with storms that produced the higest swells and the biggest stream flows during the year-long deployment.

During FY00, Professors Wash and Rosenfeld of the Naval Postgraduate School's Meteorology and Oceanography Departments, respectively, made extended visits to each of the Naval Meteorology and Oceanography Command's regional centers and facilities for the purposes of providing training, evaluating the use of METOC data, models, and tactical decision aids, and gathering information to aid in the improvement of the METOC curricula at NPS. This report represents a synopsis of their findings integrated over all of their visits. Three major roles for METOC regional centers and facilities are identified: (1) to be a source of local METOC knowledge and expertise for their area of responsibility, including familiarity with mesoscale circulations and all reliable sources of real-time data and model output; (2) to provide operational support to the fleet, including customized fused products and littoral oceanography products; and (3) to provide training for METOC personnel in regional-specific meteorology and oceanography, and continuing advanced technical training. A major finding is that technical education and training is inadequate to allow METOC personnel to take maximum advantage of the full range of data, models, and tactical decision aids available to them. Weaknesses in the quality-control and verification of METOC analysis and forecast products are also identified. A number of innovative practices at individual commands are recommended for adoption throughout the claimancy. Approved for public release; distribution is unlimited.

Six ADCP and CTD ship surveys of the continental shelf and slope in the vicinity of the Gulf of the Farallones, CA, were conducted in 1990}1992. ADCP data provide much more detail on the structure of the currents over the slope and shelf in the Gulf and reveal a persistent, largely barotropic poleward #ow with a complex mesoscale #ow "eld superimposed. The directly measured currents are not well represented by the geostrophic velocity "elds derived from hydrographic casts. Important upper-ocean circulation features include: a Slope Countercurrent (SCC), variable shelf circulation, and submesoscale eddy-like features. The SCC was present in all seasons and is believed due to a strong year-round positive wind-stress curl enhanced by Point Reyes. Its #ow was poleward throughout the upper 300 m, and often surface intensi"ed. Poleward transport in the upper 400 m was 1}3 Sv, much greater than previous geostrophic estimates for the California Current System constrained to a 500 dbar reference level. The shelf circulation was much more variable than the SCC and generally exhibited a pattern consistent with classic Ekman dynamics, responding to synoptic wind forcing. Submesoscale vortices, or eddies, often dominated the general #ow "eld. These eddies are thought to be generated by the frictional torque associated with current}topography interactions. Their centers typically have a distinct water type associated with either the SCC or the southward-#owing California Current. Higher spiciness anomalies, representing a higher percentage of Paci"c Equatorial Water (PEW), were typically found in the core of the SCC or within anticyclonic eddies. Lower (bland) spiciness anomalies, characteristic of a higher percentage of Paci"c Subarctic Water (PSAW), were associated with cyclonic eddies. While these circulation features were largely barotropic, the #ow also adjusted baroclinically to changes in the density "eld, as di!erent water types were advected by the general #ow "eld or by mesoscale instabilities in the large-scale boundary currents as they interacted with topography. Despite a seasonal cycle in regional wind and ocean temperature time series, there is no obvious seasonal pattern in the circulation. Most of the temporal variability in the current appears to be due to synoptic and interannual variations in atmospheric forcing. Because of the very dynamic three-dimensional nature of the regional circulation, the Gulf of the Farallones is likely to be a center for active mixing and exchange between the coastal and California Current waters, relative to most US west coast locales.

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. http://archive.org/details/observationsndmo109453469 US Navy (USN) author. Approved for public release; distribution is unlimited.

In conjunction with the Huntington Beach Phase III Investigation, the diurnal variability in the wind and ocean currents from July 1 - October 12, 2001 over the San Pedro Shelf is investigated. Results suggest that the diurnal currents are driven by the diurnal winds but that the strength of the ocean response is modulated by the low frequency flow regime. The spectral peak of the near-surface currents is at the diurnal frequency, which is below the inertial frequency (1.107 cpd). The diurnal currents are surface-intensified, decaying with depth to a minimum at 10-13 m and increasing slightly in strength below that. The near-surface diurnal currents are in phase across the shelf, and are close to in phase with the winds over the shelf. The amplitude modulation of the diurnal energy of the ocean currents is correlated with the direction of the low frequency flow along the shelf;the energy is enhanced when the flow is equatorward, and weak when the flow is poleward. The amplitudes of the diurnal near-surface currents are also correlated with the diurnal winds. However, the low frequency currents and winds are not well correlated. http://archive.org/details/aninvestigationo109451057 Lieutenant, United States Navy Approved for public release; distribution is unlimited.

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. http://archive.org/details/characterization1094544439 Lieutenant, United States Navy Approved for public release; distribution is unlimited.

A one year record of AVHRR satellite images, beginning October 1, 1988, was processed and evaluated to determine the source of cold, nutrient-rich water in Monterey Bay. Wind records indicated a strong correlation with the intensity of upwelling at Afio Nuevo and Point Sur as seen in numerous satellite images. Close quantitative agreement between satellite derived multi-channel sea surface temperature and in situ observation of sea surface temperature by oceanographic research ships support remote sensing as a valid tool for observing thermal gradients. http://archive.org/details/sourceofcoldwate1094544334 Commander, NOAA Corps Approved for public release; distribution is unlimited.