Jie Yu, North Carolina State University


Rip Currents and Wave-Current Interaction


Abstract: Breaking waves generate large-scale surf zone currents, e.g. alongshore and rip currents. These persisting currents provide the primary mechanisms to transport, mix and disperse water, sediment and pollutants in the shallow surf zone, where ocean currents generally do not extend. Rip currents are widely acknowledged as a major beach hazard, accounting for 80% surfzone rescues in the US. Studies in Florida show that rip currents cause more deaths than hurricanes do. Their influence on shoreline erosion and water quality on recreational beaches can be significant. Theoretical understanding of their generation mechanisms, however, has not been satisfactory, in particular on beaches lacking alongshore variability.

In this talk, I will present some recent development in modeling rip current dynamics, addressing the importance of the fully dynamical interactions of waves and currents. The existence of a hydrodynamic instability, due to this mutual interaction and leading to the formation of rip currents on alongshore uniform beaches, calls for particular attention of the multi-scale dynamics when modeling hydro-morphodynamic systems in coastal environment.

Address: Department of Civil, Construction, and Environmental Engineering. North Carolina State University. Website