Analysis of Tracer Data Collected during the SCCCAMP 1985 Intensive Measurement Periods

Abstract

This paper contains an analysis of data obtained from measurements of the concentration of tracer gases released during the four intensive measurement periods of the 1985 South-Central Coast Cooperative Air Monitoring Program (SCCCAMP). These tracer experiments were designed to document mesoscale circulation patterns in the coastal region of Santa Barbara and Ventura counties in southern California. Analyses of these concentration data are aimed at evaluating the design of the experiments, describing the movement of the tracers and comparing transport patterns to measured winds, and evaluating the ability of trajectory calculations, which are based on winds from a diagnostic wind model to reproduce those patterns of transport. The study concludes that patterns of recirculation over the 2-day period of the tests are successfully documented, revealing transport in the Santa Barbara Channel that is consistent with the circulation about the midchannel eddy, and diurnal patterns of onshore?offshore flow. Trajectories based on an interpolation of observed winds disagreed with the observed transport patterns of tracer material, especially for releases that initially traveled into the channel during the early morning hours. Apparently, the circulation in the channel and the complex flow near the coast was not sufficiently resolved by the measurement network.