Waves breaking in the shallow surf zone near the shoreline inject turbulence into the water column that may reach the bed to suspend sediment. Breaking-wave turbulence in the surf zone is, however, poorly understood, which is one of the reasons why many process-based coastal-evolution models predict coastal change during severe storms inadequately. Here, we use data collected in two natural surf zones to derive a new parameterization for the stability function C-mu that determines the magnitude of the eddy viscosity nu(t) in two-equation turbulent-viscosity models, nu(t) = C(mu)k(2)/epsilon, where k is turbulent kinetic energy and epsilon is the turbulence dissipation rate. In both data sets, the ratio of turbulence production to dissipation is small... |