Observations from the Nearshore Canyon Experiment indicate that the direction of alongshore currents often reverses along Black’s Beach (San Diego), with Southward currents at the North end of the beach, and Northward currents at the South end. Simulations (see small and large movies of simulated currents over several hours) suggest that reversals result from alongshore variability of breaking waves, which in turn results from refraction over a submarine canyon. My colleagues in this work are Prof. R.T. Guza of the Scripps Institution of Oceanography, William C. O’Rielly, Prof. Tom Herbers of the Naval Postgraduate School, and Steve Elgar and Britt Raubenheimer of the Wood’s Hole Oceanographic Institution. So far, we’ve developed a simple model for nearshore waves and currents (the fact that the wave field varies much more slowly alongshore than across-shore leads to a boundary-layer-like model for nearshore currents). In the few cases considered so far, the model predicts reversals in wave-generated forcing of alongshore currents roughly where the observed currents reversed. I’m now testing the model using the full NCEX data set. Here’s a seminar I gave at the 2008 Ocean Sciences conference with some results from this work: