Abstract
Published data on ozone increments in urban plumes are summarized, and a detailed analysis of the data set from the London, UK, Ozone Survey is presented. The survey involved 20 monitoring sites within about 100 m of the center of London, producing a large data base from which to quantify the urban plume effect. The studies indicate that hourly average O sub(3) concentrations outside the plume are well above ambient concentrations. Data are presented on plume trajectories, the influence of time of emission and travel time on incremental O sub(3) in the plume, and the diurnal profile of O sub(3) concentration at receptor sites.