Hydrographic measurements from ten Naval Oceanographic Office cruises during 19972002 were analyzed. Data included CTD soundings to 1000 dbar and shipboard ADCP current measurements. Water properties (pressure, spiciness, acceleration potential) were optimally interpolated onto the 26.0 kg/m3 and 26.8 kg/m3 isopycnal. Steric heights for the sea surface relative to 1000 dbar are compared with satellite altimeter measurements. Mean fields and their variability were described. The 26.8 kg/m3 isopycnal shoaled offshore, forming a ridge about 100 km from shore that divided low offshore and high inshore spiciness. The 26.0 kg/m3 isopycnal sloped upward toward the coast due to upwelling. Acceleration potential on the 26.0 kg/m3 isopycnal showed persistent poleward inshore flow for all cruises and with indication of weak circulation of offshore waters toward the coast to the north of Monterey Bay and weak circulation of inshore waters to the west near Point Sur. The 26.8 kg/m3 isopycnal showed a similar pattern but with stronger poleward flow along the coast. Data from individual cruises provided details on the variability of the mean fields. The most robust properties were the spiciness distributions. A distinct gradient of spiciness occurred near 12312W on both isopycnals, separating high spiciness inshore water from lower spiciness offshore.

Subjects: California Current System; Central California; CalCOFI; Monterey Bay; Naval Oceanographic Office physical oceanography surveys; isentropic analysis