Collaborative Research: Nearshore Canyon Experiment

Naval Postgraduate School, Monterey CA

Investigators

Abstract

Subject: Elgar/Herbers/Guza abstract Funds are provided for development, testing, and improvement of circulation models driven by wave propagation and wave-breaking in the presence of abrupt nearshore topography. These will be tested using data collected from a California field site with two offshore canyons. Specific objectives include: determining how surface gravity waves propagate across a complex inner shelf topography, determining how bathymetrically-induced alongshore variations of the wave field affect shoaling, breaking, and nearshore circulation, and determining the characteristics of mass exchange between the surf zone and the inner shelf in the presence of abrupt topography. Four waverider buoys over the outer and mid shelf will provide offshore wave boundary conditions for the models and characterize the refraction over the outer shelf. Pressure cells at mid shelf will identify reflected waves from Scripps Canyon. PUVs (pressure and velocity sensors) and acoustic doppler current profilers (ADCPs) over the inner shelf will characterize inner shelf and surf zone circulation and wave fields. Drifters will be deployed and tracked. Moderate wave and low wave situations will be compared in an attempt to isolate flows induced by the canyon in the absence of wave forcing. The buoys, pressure cells, and PUVs will provide estimates of the evolution of the directional wave spectrum for comparison with model output. Various inner shelf models, including the NOPP community model, will be compared to the field data.