A preliminary laboratory study of the lateral entrainment of non-local waters by a subsurface mesoscale eddy

Most previous studies of mesoscale variability in the ocean have emphasized that rings and eddies are isolated vortices embedded in relatively homogeneous water. Recent observations of eddy systems in the California Current System (CCS), however, show that at least some CCS eddy systems continue to dynamically interact with inshore coastal (cold) and offshore (warm) waters of the California Current through the process of lateral vortex entrainment. Oceanic data suggest that lateral vortex entrainment of non-local waters with significantly different temperature and salinity characteristics may partially account for the presence of high shear mixing regimes, double diffusive phenomenon and secondary circulations at depth in the vicinity of the eddies. Two different sets of laboratory experiments were conducted to assess the kinematic possibility of lateral vortex entrainment as a generation mechanism for these oceanic phenomena. The results of the laboratory studies qualitatively support the conclusion that lateral vortex entrainment could produce at least some of the observed oceanic phenomena.