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The interannual and seasonal changes in the vertical biogenic particulate fluxes, and its relation to the environmental conditions in the coastal upwelling region of Monterey Bay (Central California) has been studied since 1998 till 2006. The magnitude and composition of the settling particles presented a large interannual and seasonal variability. Organic carbon (Corg) fluxes ranged between 4 - 296 mgC·m-2·day-1 and 1 - 142 mgC·m-2·day-1 for shallow and deep sediment traps respectively. The time series of Corg vertical export was characterized by pulses of intense fluxes, that were associated to peaks of primary production, generally during upwelling periods. These results illustrate how the hydrodynamics and primary production of this coastal upwelling system regulates the vertical export of biogenic particles.

A high resolution, multi-level, primitive equation ocean model is used to investigate the combined role of wind forcing, thermohaline gradients, and coastline irregularities on the formation of currents, meanders, eddies, and filaments in the California Current System (CCS) from 22.5 deg N to 47.5 deg N. An additional objective is to further characterize the formation of the Davidson Current, seasonal variability off Baja California, and the meandering jet south of Cape Blanco. The model includes a realistic coastline and is forced from rest using climatological winds, temperatures, and salinities. The migration pattern of the North Pacific Subtropical High plays a significant role in the generation and evolution of CCS structures. In particular, variations in wind stress induce flow instabilities which are enhanced by coastline perturbations. An inshore train of cyclonic eddies, combined with a poleward undercurrent of varying seasonal depths, forms a discontinuous countercurrent called the Davidson Current north of Point Conception. Off Baja, the equator-ward surface jet strengthens (weakens) during spring and summer (fall and winter). Model results also substantiate Point Eugenia as a persistent cyclonic eddy generation area. The model equator-ward jet south of Cape Blanco is a relatively continuous feature, meandering offshore and onshore, and divides coastally influenced water from water of offshore origin, http://archive.org/details/alargescalemodel109458607, Lieutenant Commander, United States Navy, Approved for public release; distribution is unlimited.

U.S. Navy use of sonar is essential for national defense, but its potential impacts on marine mammals are not well understood. Predictive models have been developed, but the need still exists for modeling actual marine mammal reaction during Navy exercises. The goal of this thesis is to develop a tool that can assimilate data collected from on-range exercises for visualizing and quantifying marine mammal reactions to underwater sound. In this thesis, X3D Graphics is used to model an acoustic source, as well as visualize acoustic and GPS tracking data collected during exercises. Generating geo-referenced, time synchronized 3D scenes of an August 2006 test, marine mammal positions and tracks of two research boats are displayed over realistic bathymetry. From a separate August 2004 experiment, acoustic transmissions and tracking of a training target are modeled. These demonstrate the essential components needed for visualization of marine mammal reactions during an ASW exercise. Potential future work includes utilizing this system to model multiple SOAR exercises, which will provide baseline data analyses to better understand marine mammal vulnerabilities and improve Navy mitigation procedures., http://archive.org/details/extensibledxdgra109453510, US Navy (USN) author., Approved for public release; distribution is unlimited.

This thesis investigated the current patterns around San Clemente Island, California. The data were from a mooring located at Eel Point, during the period July 10, 2006 to July 23, 2007. The currents were dominated by strong poleward flow along isobaths. Semi-diurnal and diurnal tides dominated the kinetic energy and rotary spectra. Clockwise rotation dominated the rotary spectra with inertial peaks in both the near surface and near bottom depths. There were on average 2-3 current reversals every three months which appear to be unrelated to the wind stress curl. The stratification was described for the year, with one upwelling event occurring in late spring. Using wavelet analysis, it was shown that inertial/diurnal and semi-diurnal energy were present intermittently throughout the water column. The strongest modes of energy were associated with the near bottom depths. Wind stress was poorly related to the currents. Oscillations with a 2-3 day period were observed in the alongshore flow. These lasted for approximately 10 days in April 2007 and are referred to as the April event. This event was observed from mid-water to the bottom. The event had maximum velocities of 30 cm/s at mid-water and upward phase speed of 0.12 cm/s. These oscillations were rectilinear at mid-water and became counter clockwise with depth. It is speculated that this event may have been a coastally trapped wave but, with these data it cannot be determined as such. SCI/SCORE is owned and operated by Navy and supports training for the largest concentration of naval forces in the world. This thesis provides information on ocean currents and stratification on the continental shelf at SCI for SCORE and military participants to use with military exercises, regional climatologies, ocean engineering design studies, and marine mammal studies., http://archive.org/details/adescriptionofcu109454277, US Navy (USN) author., Approved for public release; distribution is unlimited.

Deep (approx. 1000 m) currents were observed off California from August 1994 to September 2009 using current meters and RAFOS floats. Current meter data were collected at nine locations for time periods ranging from two months to 76 months. A total of 144 months of float data were collected. Analysis of current meter data included histograms, progressive vector diagrams, stick plots, kinetic energy and rotary spectra, stick plots, means and standard deviations. Float data were analyzed using trajectories and calculating means, standard deviations, and diffuisivities. For current meter data, semidiurnal tidal energy dominated the kinetic energy spectrum, anticyclonic rotary motion exceeded cyclonic motion, kinetic energy was typically an order of magnitude greater than for diurnal frequencies, and kinetic energy decreased about an order of magnitude as depth increased by 1000 m. Mean speed for current meter (float) data was 6.1 (4.0) cm/s and alongshore variability exceeded across shore variability. Two floats were entrained in mesoscales eddies, one cyclonic and the other anticyclonic; the eddies moved westward at a speed of about 1 cm/s. Seasonal variability along the continental slope was marked by late summer or early fall warming; eddy kinetic energy was minimum in February, 3 cm2/s2., http://archive.org/details/atlasofdeepcurre109454318, US Navy (USN) author., Approved for public release; distribution is unlimited.

Deep (approx. 1000 m) currents were observed off California from August 1994 to September 2009 using current meters and RAFOS floats. Current meter data were collected at nine locations for time periods ranging from two months to 76 months. A total of 144 months of float data were collected. Analysis of current meter data included histograms, progressive vector diagrams, stick plots, kinetic energy and rotary spectra, stick plots, means and standard deviations. Float data were analyzed using trajectories and calculating means, standard deviations, and diffuisivities. For current meter data, semidiurnal tidal energy dominated the kinetic energy spectrum, anticyclonic rotary motion exceeded cyclonic motion, kinetic energy was typically an order of magnitude greater than for diurnal frequencies, and kinetic energy decreased about an order of magnitude as depth increased by 1000 m. Mean speed for current meter (float) data was 6.1 (4.0) cm/s and alongshore variability exceeded across shore variability. Two floats were entrained in mesoscales eddies, one cyclonic and the other anticyclonic; the eddies moved westward at a speed of about 1 cm/s. Seasonal variability along the continental slope was marked by late summer or early fall warming; eddy kinetic energy was minimum in February, 3 cm2/s2.

This thesis investigated the current patterns around San Clemente Island, California. The data were from a mooring located at Eel Point, during the period July 10, 2006 to July 23, 2007. The currents were dominated by strong poleward flow along isobaths. Semi-diurnal and diurnal tides dominated the kinetic energy and rotary spectra. Clockwise rotation dominated the rotary spectra with inertial peaks in both the near surface and near bottom depths. There were on average 2-3 current reversals every three months which appear to be unrelated to the wind stress curl. The stratification was described for the year, with one upwelling event occurring in late spring. Using wavelet analysis, it was shown that inertial/diurnal and semi-diurnal energy were present intermittently throughout the water column. The strongest modes of energy were associated with the near bottom depths. Wind stress was poorly related to the currents. Oscillations with a 2-3 day period were observed in the alongshore flow. These lasted for approximately 10 days in April 2007 and are referred to as the April event. This event was observed from mid-water to the bottom. The event had maximum velocities of 30 cm/s at mid-water and upward phase speed of 0.12 cm/s. These oscillations were rectilinear at mid-water and became counter clockwise with depth. It is speculated that this event may have been a coastally trapped wave but, with these data it cannot be determined as such. SCI/SCORE is owned and operated by Navy and supports training for the largest concentration of naval forces in the world. This thesis provides information on ocean currents and stratification on the continental shelf at SCI for SCORE and military participants to use with military exercises, regional climatologies, ocean engineering design studies, and marine mammal studies.

U.S. Navy use of sonar is essential for national defense, but its potential impacts on marine mammals are not well understood. Predictive models have been developed, but the need still exists for modeling actual marine mammal reaction during Navy exercises. The goal of this thesis is to develop a tool that can assimilate data collected from on-range exercises for visualizing and quantifying marine mammal reactions to underwater sound. In this thesis, X3D Graphics is used to model an acoustic source, as well as visualize acoustic and GPS tracking data collected during exercises. Generating geo-referenced, time synchronized 3D scenes of an August 2006 test, marine mammal positions and tracks of two research boats are displayed over realistic bathymetry. From a separate August 2004 experiment, acoustic transmissions and tracking of a training target are modeled. These demonstrate the essential components needed for visualization of marine mammal reactions during an ASW exercise. Potential future work includes utilizing this system to model multiple SOAR exercises, which will provide baseline data analyses to better understand marine mammal vulnerabilities and improve Navy mitigation procedures.

Momentum and energy transfers across the airsea interface under realistic ocean conditions are important not only in theoretical studies, but also in many applications including marine atmospheric and oceanic forecasts and climate modeling on all scales. Surface breaking waves are believed to be an important supplier of turbulent energy besides shear production of the classical turbulence theory. Waves contain a considerable amount of momentum and energy, and they redistribute these quantities over great distances. Wind waves supply energy for turbulence due to breaking. Ocean waves strongly effect the air-sea system on all scale. A part of the energy and momentum is transferred directly from the atmosphere to ocean currents while another part is transferred to surface waves. The influence of surface waves on the air-sea system has been studied experimentally and numerically by many investigators.

A high resolution, multi-level, primitive equation ocean model is used to investigate the combined role of wind forcing, thermohaline gradients, and coastline irregularities on the formation of currents, meanders, eddies, and filaments in the California Current System (CCS) from 22.5 deg N to 47.5 deg N. An additional objective is to further characterize the formation of the Davidson Current, seasonal variability off Baja California, and the meandering jet south of Cape Blanco. The model includes a realistic coastline and is forced from rest using climatological winds, temperatures, and salinities. The migration pattern of the North Pacific Subtropical High plays a significant role in the generation and evolution of CCS structures. In particular, variations in wind stress induce flow instabilities which are enhanced by coastline perturbations. An inshore train of cyclonic eddies, combined with a poleward undercurrent of varying seasonal depths, forms a discontinuous countercurrent called the Davidson Current north of Point Conception. Off Baja, the equator-ward surface jet strengthens (weakens) during spring and summer (fall and winter). Model results also substantiate Point Eugenia as a persistent cyclonic eddy generation area. The model equator-ward jet south of Cape Blanco is a relatively continuous feature, meandering offshore and onshore, and divides coastally influenced water from water of offshore origin