Submesoscale structure of the California current near San Clemente Island

Abstract

The purpose of the San Clemente Basin Experiment (SCBE) was to survey the upper ocean currents and temperature in a region southwest of San Clemente Island (SCI). To accomplish this, two cruises were made in this area during which currents were measured by using a shipboard mounted Acoustic Doppler Current profile (ADCP), and temperature was measured during the second cruise by deploying Expendable Bathythermographs (XBT). The first cruise took place during 17-21 July 1989 and the second one during 2-6 September 1989. Data indicate a variety of features. Two different flow patterns were observed. Strong poleward alongshore flow (about 40 cm/s) occurred 5-15 km west of SCI and small scale eddies were seen further offshore, i.e., farther than 15 km west of SCI. The alongshore flow intensified poleward, reaching 300 m depth. The small scale eddies have a length scale of about 10 km and are believed to be associated with larger scale horizontal shear due to the California current.