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In recent years, the application of large-scale beach nourishments has been discussed, with the Sand Motor in the Netherlands as the first real-world example. Such protruding beach nourishments have an impact on tidal currents, potentially leading to tidal flow separation and the generation of tidal eddies of length scales larger than the nourishment itself. The present study examines the characteristics of the tidal flow field around protruding beach nourishments under varying nourishment geometry and tidal conditions, based on extensive field observations and numerical flow simulations. Observations of the flow field around the Sand Motor, obtained with a ship-mounted current profiler and a set of fixed current profilers, show that a tidal eddy develops along the northern edge of the mega-nourishment every flood period. The eddy is generated around peak tidal flow and gradually gains size and strength, growing much larger than the cross-shore dimension of the coastline perturbation. Based on a 3 week measurement period, it is shown that the intensity of the eddy modulates with the spring-neap tidal cycle. Depth-averaged tidal currents around coastline perturbations are simulated and compared to the field observations. The occurrence and behavior of tidal eddies is derived for a large set of simulations with varying nourishment size and shape. Results show that several different types of behavior exist, characterized by different combinations of the nourishment aspect ratio, the size of the nourishment relative to the tidal excursion length, and the influence of bed friction., Coastal Engineering, Environmental Fluid Mechanics

The inertial frequency is nearly diurnal at 308N latitude which transects the northeastern Gulf of Mexico (NeGoM). At this latitude, near-surface inertial oscillations can amplify due to resonance with diurnal wind forcing. Diurnal oscillations have also been attributed to diurnal tidal forcing in this region. Because tidal forcing, wind forcing, and inertial oscillations are nearly diurnal, a unique series of comparative analyses are required to determine their relative influence on surface circulation. By comparing surface currents obtained by HF radar to predictions of the inertial response to wind forcing and barotropic tidal currents, it is found that diurnal oscillations in the NeGoM were predominantly due to wind-forced inertial oscillations in June 2010. The analyses provide a unique spatiotemporal perspective of inertial oscillations in the NeGoM where there is evidence of propagation, frequency and phase shifts, and amplitude variability. Because inertial oscillations mix the ocean differently than the tides, these results provide insight into how inertial oscillations potentially mixed oil from the Deepwater Horizon spill in June 2010. Near-diurnal oscillations during the winter were found to be predominantly due to tidal forcing when wind-driven inertial oscillations were diminished due to a presumably deeper mixed layer.

A five-month study was performed on an energetic, dissipative beach on a climatologically Mediterranean coastline to explore the wind stress and buoyancy flux. An eddy covariance system was deployed in the intertidal zone resulting in 1088 hours of quality-controlled flux observations at elevations of 1, 3, and 6m on a sandy beach in Monterey, CA. The wind stress angle relative to the mean wind direction varied as much as 31o, representing one standard deviation, with a range of ±151o. The variations were dependent on the wind angle relative to the swell direction and shoreline, which directed the stress vector to the left for winds approaching from 0o>θ>-45o and to the right for winds approaching from -45o>θ>-80o, where 0o is onshore. The stress angle was independent of stability, stress, and wind speed. Air-ocean temperature differences produced unstable conditions 88% of the time in contrast to the near neutral conditions that dominate the open ocean. Based on flux footprints, the surf zone was found to be a source of positive buoyancy and heat flux contributing to the unstable conditions. Minimum buoyancy fluxes were observed with the flux footprints that were farther offshore centered outside the surf zone, resulting in stable conditions.

This paper is not subject to U.S. copyright. The definitive version was published in Estuarine, Coastal and Shelf Science 150, Pt.B (2014): 325-331, doi:10.1016/j.ecss.2014.03.025., Amplitudes of semi-diurnal tidal fluctuations measured at an ocean inlet system decay nearly linearly by 87% between the ocean edge of the offshore ebb-tidal delta and the backbay. A monochromatic, dynamical model for a tidally choked inlet separately reproduces the evolution of the amplitudes and phases of the semi-diurnal and diurnal tidal constituents observed between the ocean and inland locations. However, the monochromatic model over-predicts the amplitude and under-predicts the lag of the lower-frequency subtidal and fortnightly motions observed in the backbay. A dimensional model that considers all tidal constituents simultaneously, balances the along-channel pressure gradient with quadratic bottom friction, and that includes a time-varying channel water depth, is used to show that that these model-data differences are associated with nonlinear interactions between the tidal constituents that are not included in non-dimensional, monochromatic models. In particular, numerical simulations suggest that the nonlinear interactions induced by quadratic bottom friction modify the amplitude and phase of the subtidal and fortnightly backbay response. This nonlinear effect on the low-frequency (subtidal and fortnightly) motions increases with increasing high-frequency (semi-diurnal) amplitude. The subtidal and fortnightly motions influence water exchange processes, and thus backbay temperature and salinity., We thank the Office of Naval Research (N0001411WX20962; N0001412WX20498) for funding.

Aerial videos of the surf zone at Sand City, Monterey Bay, CA, were acquired using an unmanned aerial vehicle. Videos of 26 individual bores were converted to still images and were georectified, georeferenced, and post processed. The size, shape, and evolution of the wave generated foam patterns within the surf zone were analyzed. The results were tested against two existing hypotheses of foam pattern generation, Obliquely Descending Eddies (ODEs) and self-organization due to bubble rise. Three foam regions within the surf zone were recognized. The largest region, the foam mat, encompasses nearly the entire surf zone and is described as a mat of foam that develops obvious foam holes. The areas of the holes grew in area and elongated with time. The results were inconsistent with the two theories of foam hole generation. The fringe region is the most seaward foam region and is marked with circular foam rings that become larger in area and more distinct with time. The fringe region data are contrary to observations of ODEs but is consistent with the theory of self-organization due to bubble rise. The gap region, located between the plunge point and the splash up created by the bore collapse, is marked by horizontal foam tubes oriented in the cross-shore direction. The foam tubes are likely created in the convergent region between two counter-rotating vortices.

Larvae of many intertidal species develop offshore and must cross the surf zone to complete their onshore migration to adult habitats. Depending on hydrodynamics, the surf zone may limit this migration, especially on reflective rocky shores. As a logistically tractable analog of a rocky shore environment, we carried out a comprehensive biological and physical study of the hydrodynamics of a steep reflective sandy beach. Holoplankton and precompetent larval invertebrates were much less abundant within the surf zone than offshore, and their concentrations inside and outside the surf zone were not significantly correlated, suggesting that they were not entering the surf zone. Persistent offshore flow throughout the water column at the outer edge of the surf zone may prevent these organisms from entering the surf zone. In contrast, the concentrations of detritus and a competent larval invertebrate (i.e. cyprids), while also not significantly correlated with concentrations offshore, were frequently more concentrated in the surf zone than offshore. Within the surf zone, the concentration of detritus was significantly correlated with concentrations of competent larval invertebrates (barnacles, gastropods, polychaetes, and bopyrid amphipod) and organisms that may be associated with detritus (amphipods and harpacticoid copepods). These concentrations were significantly negatively correlated with average daily wave height. We hypothesize that detritus and larvae enter the surf zone near the bottom during calm wave conditions by a process of near-bottom streaming. Near-bottom streaming is associated with all surf zones and may be a general mechanism for onshore transport of larvae close to the coast.

This study investigates the potential of rotary wing unmanned aerial vehicles (UAVs) to monitor the surfzone. This paper shows that these UAVs are extremely flexible surveying platforms that can gather nearcontinuous moderate spatial resolution and high temporal resolution imagery from a fixed position high above a study site. The rotary wing UAVs used in this study can fly for ;12 min with a mean loiter radius of 1–3.5m and a mean loiter error of 0.75–4.5 m. These numbers depend on the environmental conditions, flying style, battery type, and vehicle type. The images obtained from the UAVs, and in combination with surveyed ground control points (GCPs), can be georectified to a pixel resolution between 0.01 and 1m, and a reprojection error—that is, the difference between the surveyed GPS location of a GCP and the location of the GCP obtained from the georectified image—of O(1 m). The flexibility of rotary wing UAVs provides moderate spatial resolution and high temporal resolution imagery, which are highly suitable to quickly obtain surfzone and beach characteristics in response to storms or for day-to-day beach safety information, as well as scientific pursuits of surfzone kinematics on different spatial and temporal scales, and dispersion and advection estimates of pollutants.

Short-term observations of sea surface elevations h along the 10-m isobath and long-term observations inside and outside of a large bay (Monterey Bay, CA) were obtained to describe the nodal structure of the modes 0–3 seiches within the bay and the low-frequency (,346 cpd) seiche forcing mechanism. The measured nodal pattern validates previous numerical estimates associated with a northern amplitude bias, though variability exists across the modal frequency band, particularly for modes 0 and 1. Low-frequency oceanic h white noise within seiche frequency bands (24–69 cpd) provides a continuous resonant forcing of the bay seiche with a h2 (variance) amplification of 16–40 for the different modes. The temporal variation of the oceanic h white noise is significantly correlated (R250.86) at the 95% confidence interval with the bay seiche h that varies seasonally. The oceanic h white noise is hypothesized as being from low-frequency, free, infragravity waves that are forced by short waves.

Rogue waves have presented unpredictable, dire hazards to mariners since the dawn of seafaring. Even in benign seas, isolated rogue waves can severely endanger ships and crews, even accounting for their disappearance. Better understanding of rogue wave generation will enhance safety of maritime operations. This study examines surface height data from wave resolving drifters (WRDs) deployed in groups of 30–50 in the Mouth of the Columbia River (MCR) during the peak of ebb tide in May and June of 2013. Over three separate collection days, effects of opposing currents and bathymetry on swell and wind waves were analyzed as WRDs headed to sea from the MCR. Wave significance was identified based on the local sea state within 1 km of the drifter location. Wave height histograms were calculated from regional wave ensembles and compared with the theoretical Rayleigh distribution of a narrow band, Gaussian wave field. Generally, wave height data in the MCR follow Rayleigh distribution well. Areas over shallower bathymetry of the MCR Bar and predominant waves from the west create intense sea state amplification and rogue wave occurrence, and right-tail deviation from the Rayleigh pdf. Isolated extreme waves and trains of large waves were observed on the Bar.

The cross-shore exchange of material is examined on beaches of varying morphology and hydrodynamics. On a dissipative, rip-channeled beach in Monterey, California, field measurements of the rip current vertical structure reveal depth-uniform flows inside the surf zone, and surface-dominated flows with rotation over depth outside the surf zone. Aperiodic, very low frequency pulsations in the near-surface velocity were found to control the mean rip current flow. Observations of Lagrangian surface drifters released on the inner shelf resulted in a new theory of material transport on a rip-channeled beach, where rip current pulses episodically expel material offshore through rip channels, and momentum-driven surfzone circulations pull the material back onshore over shoals to satisfy a mass balance, with no material being completely removed from the nearshore system. Advection and diffusion processes on a steep, reflective beach at Carmel River State Beach, California, are also investigated using measurements of the temporal and spatial evolution of dye released in the surf zone. A net offshore transport did exist, and the mixing and transport processes inside and outside the surf zone were independent. Overall, this work provides new insights into the fate of material transported between the surf zone and inner shelf on natural beaches.

Despite the importance of sea breeze, only Hendrickson and MacMahanâ s research has been done to determine sea breeze effects in Monterey Bay; other than that not much research has been done. In this thesis, CODAR SeaSonde radars are used to map the surface current in Monterey Bay. Temperature, wind speed and wind direction are analyzed for five locations to establish the algorithm for determining the sea breeze days in Monterey Bay. Harmonic analysis is used to understand the relationship between sea breeze and high frequency (HF) radar-derived surface currents. To explain the cause of the peaks and lows in the amplitude of the sea breeze as shown by the harmonic analysis, coastal jet influences, boundary layer height changes, temperature gradient variations and cloudiness are investigated. Current patterns clearly respond to changing sea breeze strength with the strongest amplitudes corresponding to days with fully developed coastal jets. No coastal jet, lower amplitude sea breeze days, however, appear to have a more classical response in terms of wind direction changes. It is understood that rapid decrease of the amplitude of sea breeze in harmonic analysis is the day with sea breeze including obvious wind shifting, and rapid increase is the day when strong synoptic effect is seen obviously over the region.

CARTHE (http://carthe.org/) is a Gulf of Mexico Research Initiative (GoMRI) consortium established through a competitive peer-reviewed selection process. CARTHE comprises 26 principal investigators from 14 universities and research institutions distributed across four Gulf of Mexico states and other four states. It fuses into one group investigators with unique scientific and technical knowledge and extensive publications related to oil fate/transport processes, oceanic and atmospheric turbulence, air-sea interactions, tropical cyclones and winter storms, and coastal and nearshore modeling and observations. Our primary goal is to accurately predict the fate of hydrocarbons released into the environment. Achieving this goal is particularly challenging since petroleum releases into the environment interact with natural processes across six orders of magnitude of time and space scales. We are developing a multi-scale modeling tool by incorporating state-of-the-art hydrophysical models, each applicable for a restricted range of scales, into a single, interconnected modeling system to predict the physical dispersal of hydrocarbons across scales ranging from the microscale at the wellhead to oceanic and atmospheric mesoscales. CARTHE is also conducting novel in-situ observations and laboratory experiments specifically designed for quantifying submesoscale dispersion as well as for both model validation and parameterization. Finally, we are providing a robust set of uncertainty metrics and analysis tools to assess model performance and quantify predictive uncertainty.

Competent larvae of intertidal invertebrates have to migrate toward shore for settlement; however, their migration through the surf zone is not understood. We investigated larval transport mechanisms at a ripchanneled beach. Because tracking larvae in the surf zone is infeasible, we used a three-dimensional biophysical model to simulate the processes. The coupled model consists of a physical module for currents and waves, and a biological module for adding larval traits and behaviors as well as Stokes drift to Lagrangian particles. Model calculations were performed with and without onshore wind forcing. Without wind, wave-driven onshore streaming occurs in the bottom boundary layer outside the surf zone. With onshore wind, onshore currents occur near the surface. In the surf zone, offshore-directed rip currents and compensating onshore-directed currents over shoals are formed in both no-wind and wind cases. In the biological module, neutral, negative, and positive buoyant particles were released offshore. Additionally, particles either sank in the presence of turbulence or not. Two scenarios achieved successful onshore migration: Negatively buoyant larvae without wind forcing sink in the turbulent bottom boundary layer and are carried onshore by streaming; positively buoyant larvae drift toward shore in wind-driven surface currents to the surf zone, then sink in the turbulent surf zone and remain near the bottom while transported shoreward. In both cases, the larval concentration is highest in the rip channel, consistent with field data. This successful result is only obtained if turbulence-dependent sinking behavior and Stokes drift are included in the transport of larvae.

Concurrent Lagrangian and Eulerian observations of rotational, low-frequency (1024 to 1022 Hz) surfzone eddies are compared. Surface drifters were tracked for a few hours on each of 11 days at two alongshore uniform beaches. A cross-shore array of near-bottom current meters extended from near the shoreline to seaward of the surfzone (typically 100 m wide in these moderate wave conditions). Lagrangian and Eulerian mean alongshore velocities V are similar, with a midsurfzone maximum. Cross-shore dependent Lagrangian (rL) and Eulerian (rE) rotational eddy velocities, estimated from low-pass filtered drifter and current meter velocities, respectively, also generally agree. Cross-shore rotational velocities have a midsurfzone maximum whereas alongshore rotational velocities are distributed more broadly. Daily estimates of the Lagrangian time scale, the time for drifter velocities to decorrelate, vary between 40 and 300 s, with alongshore time scales greater than cross-shore time scales. The ratio of Lagrangian to apparent Eulerian current meter decorrelation times TL/TA varies considerably, between about 0.5 and 3. Consistent with theory, some of the TL/TA variation is ascribable to alongshore advection and TL/TA is proportional to V/r, which ranges between about 0.6 and 2.5. Estimates of TL/TA vary between days with similar V/r suggesting that surfzone Lagrangian particle dynamics vary between days, spanning the range from ‘‘fixed-float’’ to ‘‘frozen-field’’ [Lumpkin et al., 2002], although conclusions are limited by the statistical sampling errors in both TL/TA and V/r.

The goal of our effort is to understand river and inlet fluid dynamics through in situ field observations and model validation.

The overall goal is to improve the predictive capability and skill of Delft3D to simulate complex hydrodynamics in an inlet setting in which tides, river discharge, winds, waves, and bottom friction are all important.

The shoreward and seaward propagating tidal wave components were determined using four co-located pressure and velocity sensors longitudinally deployed in Elkhorn Slough, Monterey Bay, CA, to describe tidal wave evolution and distortion. Elkhorn Slough is short, reflective (~100%) estuary consisting of a narrow, gently sloping main channel and vast marsh and mud flats near the landward boundary. The amplitude reflection for the astronomical tidal constituent is ~90%, whereas the distortion, described by summing all non-astronomical tidal amplitudes, reflection is large (125%) for all stations stating that the seaward tidal wave is more distorted than the shoreward tidal wave. It was found that the reflective time, defined as the time it takes the tidal wave to propagate to the landward boundary and back, varies as function of tidal elevation. Surprisingly, the reflective time increases with increasing tidal elevation contrary to the hypothesis that the shallow-water tidal wave phase speed increases with increasing tidal elevation, resulting in a reduced time. The landward end of the slough has vast low-lying marshes and mud flats that are inundated during higher tidal elevations, causing the effective (average) wave depth to decrease with increasing tide elevation, which explains why the tidal wave phase speed decreases instead of increasing. The elevation-dependent reflective time caused by a time-varying wave phase speed modifies the shape of the seaward tidal wave relative to the shape of the shoreward tidal wave, which explains the evolution and distortion of a tidal wave in a reflective slough.

Wave blocking in river inlets is examined using the NHWAVE (Non-Hydrostatic Wave) model under development. Blocking flows at river inlets are a significant hazard to navigation. Refractive and shoaling effects contribute to the enhancement of wave field energy, causing instabilities and breaking, resulting in energy dissipation and transfer at the blocking point. The non-linearity of wave-current interactions and wave breaking makes the dynamics of blocking flows difficult to model. Current efforts to use wave-averaged models are insufficient to describe the complex dynamics that occur within one or two wavelengths of a blocking point. NHWAVE uses the non-hydrostatic, incompressible Navier-Stokes equations to model fully dispersive wave processes in the time domain. Monochromatic wave cases are explored and compared with lab experiments of energy dissipation due to wave breaking under conditions of strong opposing current, conducted in 2002 at the University of Delaware by A. Chawla and T. J. Kirby. The model was initially unable to resolve the boundary conditions necessary to model wave blocking in a tank domain. However, developments to the numerical scheme in NHWAVE have advanced its capability in this regard. Due to the difficulties of modeling the dynamics of wave blocking and the boundary conditions in a wave tank, only preliminary results were obtained. NHWAVE needs further development; it shows promise, however, to be able to predict wave reflection, blocking, and dissipation on a strong opposing current.

LONG-TERM GOALS: The goal of our effort is to understand river and inlet fluid dynamics through in situ field observations and model validation.

Onshore transport of intertidal invertebrate larvae at a reflective (steep beach slope) and an intermediate (relatively gradual beach slope) beach is modeled. Physical model calculations are conducted with the measured bathymetry data and averaged wave data obtained during the summer of 2010 at Sand City beach, CA (intermediate beach) and the summer of 2011 at Carmel River State Beach, CA (reflective beach). The physical model output is then used in a Lagrangian larval tracking model. Our results show that larval delivery to the surf zone is higher at the more dissipative beach than at the more reflective beach, and this is consistent with the larval recruitment study by Shanks et al. (2010). Also, two possible factors for the successful onshore larval transport on an intermediate beach, turbulent-dependent sinking behavior and buoyancy of larvae, are not always necessary in the case of a reflective beach.

LONG-TERM GOALS: The overall goal is to improve the predictive capability and skill of Delft3D to simulate complex hydrodynamics in an inlet setting in which tides, river discharge, winds, waves, and bottom friction are all important.

The main objectives of our FY12 effort were to: 1) measure the intra-tidal three dimensional flow velocity distribution; 2) measure the concurrent suspended sediment concentration (the accompanying sediment transports will be obtained by multiplying the concentration with the simultaneously measured velocity); 3) extract the tidal flow circulation with Delft 3D to retrieve the residual flow circulation associated with the forcing by waves, wind and density differences; 4) verify Delft3D in predicting the complex velocity field and concurrent sediment transports under a range of environmental conditions (i.e. waves, wind and potentially stratification)., The original document contains color images. Prepared in collaboration with Rosenstiel School of Marine and Atmospheric Science, Miami, FL, under grant nos. N00014-10-1-0409, N00014-10-1-0379.

Projecting naval forces in littoral areas requires a thorough understanding of the environmental processes that take place in those areas, especially ocean wave evolution, and the associated surf and wave-driven currents. The transformation of wave spectra in coastal environments is predicted with numerical models that include the effects of refraction, nonlinear wave-wave interactions, and parameterizations of wave breaking and bottom friction. This thesis presents a comparison between a new field data set and model predictions of wave transformation in shallow water. An array of 16 wave-measuring instruments was deployed outside the surf zone on the sandy sea bed of Martha's Vineyard's inner continental shelf in the fall of 2007. Data from these instruments are analyzed and the performance of the spectral wave prediction model SWAN (Simulating WAves Nearshore) is tested against the observations. The observations generally show gradual wave decay towards the shore with a reduction of as much as 15% of the incident wave height across only 4 km of continental shelf. Wave height variability is observed in both the crossshore and the alongshore directions, suggesting that the effect of bottom processes on wave energy is twodimensional. Comparisons of these observations with SWAN model predictions show that both bottom friction and refraction play a dominant role in the wave energy transformation outside the surf zone. Overall, the spectral wave decay is handled well by SWAN with any of the bottom friction parameterizations activated, including the widely used JONSWAP (Hasselmann et al., 1973) empirical parameterization. Deactivating bottom friction in SWAN yields a slight overprediction of nearshore wave heights., http://archive.org/details/ocesurfacewavetr109454532, Spanish Navy author., Approved for public release; distribution is unlimited.

An ephemeral river is a seasonal river that flows into the ocean, forming an inlet at certain times of the year, and the river is blocked by a barrier beach that usually forms a lagoon during the rest of the year. Ephemeral rivers are important for both military and civilian communities because these areas are susceptible to rapid, unpredictable flooding and beach breaching. Wave overtopping of barrier beaches is the first step to modeling beach breaching. Carmel River State Beach, in central California, acts a barrier beach for the Carmel River that flows into the Carmel Lagoon. Lagoon height changes were converted to volume changes by a stage-volume curve, then center differenced and averaged to provide total volume rates of change in the lagoon. The van der Meer and Janssen (VJ), European, and Hedges and Reis (HR) overtopping models were compared. The lagoon volume rate of change was compared to the predicted model rate of change for three different overtopping cases in 2006, 2008, and 2009. The models performed similarly with R² values of 0.72-0.86 for narrow banded cases, with an average reduction factor of 0., http://archive.org/details/waveovertoppingo109454551, US Navy (USN) author., Approved for public release; distribution is unlimited.

Nearshore depths for Waimanalo Beach, HI, are extracted from optical imagery, taken by the WorldView-2 satellite on 31 March 2011, by means of automated wave kinematics bathymetry (WKB). Two sets of three sequential images taken at intervals of about 10 seconds are used for the analyses herein. Water depths are calculated using a computer program that registers the images, estimates the currents, and then uses the linear dispersion relationship for surface gravity waves to estimate depth. Depths are generated from close to shore out to about 20 meters depth. Comparisons with SHOALS LIDAR bathymetry values show WKB depths are accurate to about half a meter, with R2 values of 90%, and are frequently in the range of 1020 percent relative error for depths ranging from 216 meters.

An intercomparison of Datawell accelerometer buoys, Datawell GPS buoys, and prototype GPS buoys was conducted to determine the viability of using off-the-shelf GPS receivers to measure ocean surface waves. In the experiment, conducted off the coast of California near Bodega Bay, clusters off Datawell and prototype GPS buoys were deployed to collect ocean surface wave measurements. The first phase of the research was an intercomparison of wave measurements from a Datawell accelerometer sensor, the Magellan MMCX GPS receiver and the GlobalSat MR-350 GPS receiver. The Datawell accelerometer and the Magellan MMCX receiver measurements of both vertical and horizontal wave orbital excursions are in good agreement. The GlobalSat MR-350 receiver also accurately resolved horizontal wave orbital displacements but failed to reproduce the vertical wave excursion measurement by the accelerometer sensors. The second phase of the project was an independent intercomparison between the Datawell MK-II accelerometer buoys, Datawell Waverider GPS buoys, and the prototype GPS buoys built by the NPS team using the Magellan MMCX receiver. The intercomparison showed good agreement between the off-the-shelf GPS buoys, the newer Datawell GPS buoys as well as the traditional Datawell accelerometer buoys in the energetic part of the wave spectrum., http://archive.org/details/fieldevaluationo109455117, US Navy (USN) author, Approved for public release; distribution is unlimited.

Subaqueous beach profiles are obtained for littoral regions near Camp Pendleton, CA, using observations of wave motion. Imagery was acquired from WorldView2 Satellite on 24 March 2010. Two sequential images taken 10 seconds apart are used for the analyses herein. Water depths were calculated using linear dispersion relationship for surface gravity waves. Depth profiles were established from shoreline out to 1 kilometer offshore and depths of up to 15 meters. Comparisons with USGS DEM values show agreement within five percent in the surf zone (shoreline to wave breaking) and one percent outside the surf zone (offshore of wave breaking)., http://archive.org/details/coastalbathymetr109455519, Approved for public release; distribution is unlimited.