Events Calendar

Astani CEE Ph.D. Seminar

Speaker: Falk Feddersen Associate Research Oceanographer , Integrative Oceanography Division Scripps Institution of Oceanography, UCSD

Talk Title: Surfzone eddies in strong alongshore currents: Forced or Instabilities?

Abstract:

Beaches throughout the United States are chronically impacted by poor water quality, making swimmers sick and affecting coastal economies. Run-off pollution often drains directly into the surfzone and the mechanisms dispersing and diluting pollution or other tracers (e.g. larvae) are not clear. Surfzone 2D turbulent eddies are the dominant mechanisms for surfzone dispersion and dilution, and these eddies are generated either from a shear-instability of the alongshore current (“shear-waves''), from finite-crest length breaking of individual waves, or from alongshore gradients in wave-group forcing, which have distinct length-scales. SandyDuck based observations of surfzone eddies are compared to funwaveC model simulations. Finite-crest length breaking induces energy at much larger frequencies and wave-lengths than a NSWE model. The relative contributions of shear instabilities and finite-crest length breaking on the momentum and vorticity dynamics are examined. The results will have implications for modeling the dispersion and dilution of surfzone tracers (whether fecal indicator bacteria, sediment, or larvae).


Host: Dr. Patrick Lynett

Location: John Stauffer Science Lecture Hall (SLH) - 102

Audiences: Everyone Is Invited

Contact: Evangeline Reyes