Rip current review

Abstract

Rip currents are shore-normal, narrow, seaward-flowing currents that originate within surf zone, extend seaward of the breaking region (rip head), and can obtain relatively high velocities. Within the last decade, there have been a significant number of laboratory and field observations within rip current systems. An overview of rip current kinematics based on these observations and the scientific advances obtained from these efforts are synthesized. Rip current flows are partitioned into mean, infragravity, very low frequency (vorticity), and tidal contributions, and it is found that each contributes significantly to the total. Data from the laboratory and the field suggest that the rip current strength increases with increasing wave energy and decreasing water depths. The maximum mean current occurs inside the surf zone, where the maximum forcing is present owing to the dissipation of waves.