Author Description

The synoptic climatology of ozone for Southern Ontario has shownthat, over the 1976-1981 period, average summer ozone (O3)concentrations follow a relationship similar to that reported forevent analysis during periods of high O3 concentration. Highestaverage concentrations, 36 parts per billion (ppb), occur with"back of the high" situations while lowest average concentrations(20 ppb) occur with "front of the high" situations. Withsimilar weather events in the winter, the pattern is reversedwith highest average O3 concentrations on the "front of thehigh" (19 ppb) and lowest average concentrations on the "back ofthe high" (13 ppb). Concentration of O3 in the "front of thehigh" sector is due in part, to the intrusion of O3 in thevicinity of storms from the stratoshpere. The seasonal variationof average concentrations in these situations is low ranging from14 to 26 ppb.