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The likelihood of rip currents as a function of water depth (tidal level), incident wave height, period, direction, and spectral spreading in both frequency and direction is investigated with a Boussinesq numerical model (FUNWAVE) for alongshore uniform, moderately variable, and strongly variable bathymetry, providing two- dimensional probability distributions of rip-current occurrence along the coast. The simulations suggest that over strongly irregular alongshore bathymetry rip-current likelihood increases with longer wave periods and narrower directional spectra. In contrast, over more uniform alongshore bathymetry, rip current likelihood in- creases with shorter wave periods and broader directional spectra. The simulations suggest that as bathymetric variability increases, the effects of different incident wave fields decreases.
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Performance of a One-Dimensional Model of Wave-Driven Nearshore Alongshore Tracer Transport and Decay with Applications for Dry Weather Coastal Pollution
Dry weather pollution sources cause coastal water quality problems that are not accounted for in existing beach advisory metrics. A 1D wave-driven advection and loss model was developed for a 30 km nearshore domain spanning the United States/Mexico border region. Bathymetric nonuniformities, such as the inlet and shoal near the Tijuana River estuary mouth, were neglected. Nearshore alongshore velocities were estimated by using wave properties at an offshore location. The 1D model was evaluated using the hourly output of a 3D regional hydrodynamic model. The 1D model had high skill in reproducing the spatially averaged alongshore velocities from the 3D model. The 1D and 3D models agreed on tracer exceedance or nonexceedance above a human illness probability threshold for 87% of model time steps. 1D model tracer was well-correlated with targeted water samples tested for DNA-based human fecal indicators. This demonstrates that a simple, computationally fast, 1D nearshore wave-driven advection model can reproduce nearshore tracer evolution from a 3D model over a range of wave conditions ignoring bathymetric nonuniformities at this site and may be applicable to other locations.
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- PAR ID:
- 10483937
- Publisher / Repository:
- ACS Publications
- Date Published:
- Journal Name:
- Environmental Science & Technology
- Volume:
- 57
- Issue:
- 39
- ISSN:
- 0013-936X
- Page Range / eLocation ID:
- 14674 to 14683
- Subject(s) / Keyword(s):
- nearshore pollution modeling water quality waves
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1021/acs.est.2c08656
