Case Studies in Wave-Current Interaction

James C. McWilliams
UCLA

Surface gravity waves have significant dynamical influences on oceanic
currents, especially in the upper ocean and near the coastline. Wave
effects are being incorporated in circulation models, including ROMS,
based on a multi-scale asymptotic theory that identifies the principal
conservative effects --- vortex force, material transport, and
Bernoulli-head pressure gradient --- and on parameterizations of
non-conservative wave breaking. Several case studies will be
discussed: (1) stably stratified, surface Ekman currents under high
winds; (2) deep-water infragravity wave generation and global seismic
hum; and (3) shear instability of wave-generated littoral currents.