A description of the currents on the continental shelf near Eel Point, San Clemente Island, California, from July 10, 2006, to July 23, 2007

Abstract

This thesis investigated the current patterns around San Clemente Island, California. The data were from a mooring located at Eel Point, during the period July 10, 2006 to July 23, 2007. The currents were dominated by strong poleward flow along isobaths. Semi-diurnal and diurnal tides dominated the kinetic energy and rotary spectra. Clockwise rotation dominated the rotary spectra with inertial peaks in both the near surface and near bottom depths. There were on average 2-3 current reversals every three months which appear to be unrelated to the wind stress curl. The stratification was described for the year, with one upwelling event occurring in late spring. Using wavelet analysis, it was shown that inertial/diurnal and semi-diurnal energy were present intermittently throughout the water column. The strongest modes of energy were associated with the near bottom depths. Wind stress was poorly related to the currents. Oscillations with a 2-3 day period were observed in the alongshore flow. These lasted for approximately 10 days in April 2007 and are referred to as the April event. This event was observed from mid-water to the bottom. The event had maximum velocities of 30 cm/s at mid-water and upward phase speed of 0.12 cm/s. These oscillations were rectilinear at mid-water and became counter clockwise with depth. It is speculated that this event may have been a coastally trapped wave but, with these data it cannot be determined as such. SCI/SCORE is owned and operated by Navy and supports training for the largest concentration of naval forces in the world. This thesis provides information on ocean currents and stratification on the continental shelf at SCI for SCORE and military participants to use with military exercises, regional climatologies, ocean engineering design studies, and marine mammal studies.