in the summer of 1991, a 4-week international field experiment was conducted to measure ozone concentrations and fluxes in the san joaquin valley, california. the field data will be used to improve understanding of the exchange processes occurring between the atmosphere and various types of vegetation. the data will also be used to develop a comprehensive computer model for ozone transport and deposition in the valley. canadian participation in this experiment comprised a series of low level flights, with repeated passes over agricultural sites (cotton, grapes, grassland, orchards, tomatoes), as well as regional-scale flights and higher-level soundings to document atmospheric conditions. specific information is given on the aircraft instrumentation, software, recorded parameters, analysis procedures, data formats, flight characteristics, and data collected on fluxes of sensible and latent heat, co2, momentum, and ozone. the highest ozone deposition velocities were measured over corn and cotton sites. a correlation is suggested between the measured greenness index and the ozone deposition velocity; this relationship is almost independent of the type of vegetation overflown. this in turn suggests a method for characterizing the deposition velocities for the entire valley using remotely sensed data from satellites