Numerical simulations of larval transport into a rip-channeled surf zone
Fujimura, Atsushi G.
Reniers, Ad J.H.M.
Paris, Claire B.
Shanks, Alan L.
MacMahan, Jamie H.
Morgan, Steven G.
MetadataShow full item record
Competent larvae of intertidal invertebrates have to migrate toward shore for settlement; however, their migration through the surf zone is not understood. We investigated larval transport mechanisms at a ripchanneled beach. Because tracking larvae in the surf zone is infeasible, we used a three-dimensional biophysical model to simulate the processes. The coupled model consists of a physical module for currents and waves, and a biological module for adding larval traits and behaviors as well as Stokes drift to Lagrangian particles. Model calculations were performed with and without onshore wind forcing. Without wind, wave-driven onshore streaming occurs in the bottom boundary layer outside the surf zone. With onshore wind, onshore currents occur near the surface. In the surf zone, offshore-directed rip currents and compensating onshore-directed currents over shoals are formed in both no-wind and wind cases. In the biological module, neutral, negative, and positive buoyant particles were released offshore. Additionally, particles either sank in the presence of turbulence or not. Two scenarios achieved successful onshore migration: Negatively buoyant larvae without wind forcing sink in the turbulent bottom boundary layer and are carried onshore by streaming; positively buoyant larvae drift toward shore in wind-driven surface currents to the surf zone, then sink in the turbulent surf zone and remain near the bottom while transported shoreward. In both cases, the larval concentration is highest in the rip channel, consistent with field data. This successful result is only obtained if turbulence-dependent sinking behavior and Stokes drift are included in the transport of larvae.
The article of record as published may be located at http://dx.doi.org/10.4319/lo.2014.59.4.1434
Showing items related by title, author, creator and subject.
The impact of synoptic-scale flow on sea breeze front propagation and intensity at Eglin Air Force Base Weaver, James C. (Monterey California. Naval Postgraduate School, 2006-03);This study investigates the impact of the synoptic-scale flow on the propagation and intensity of the sea breeze front at Eglin Air Force Base. The 925 mb wind direction and speed from the 12 UTC Tallahassee sounding was ...
Asanuma, Hiromi (Monterey, California. Naval Postgraduate School, 1999-06-01); NPS-OC-99-01During 1997-1998, oceanographic conditions off Central California were monitored by means of a series of thirteen cruises which measured water properties along an oceanographic section perpendicular to the California Coast. ...
Brennan, John Frederick; Meaux, Richard P. (Monterey, California. Naval Postgraduate School, 1964);The nearshore circulation off a long sand beach at the southern end of Monterey Bay, California, was studied during February and March 1964. In preparation for the study, various types of floats were tested, and a resume ...