Book Description

The California Front, the boundary region between the Eastern North Pacific Central Water and the Transition Water, is approximately 170 mi wide, and is centered approximately 530 mi off the California Coast. (This region contains large anomalies in water structure that influence sound transmission.) The location of the maximum horizontal change in water properties was established from serial oceanographic stations, and the detail of thermal and current structures was obtained with a towed thermistor chain and attached current meters. The boundary is characterized by stronger than normal horizontal temperature (and salinity) gradients; large vertical changes in isotherm depths; temperature inversions; a large surface temperature gradient; and a thermocline separation. Temperature inversions produce sound channels above the level of increased temperature. Measured current shear shows relative current in the upper layers to be in a southerly direction on the eastern side of the boundary and in a westerly direction on the western side; however, current shear inside the boundary regions was in diverse directions. (Author).