Extent of photochemical smog reaction in the Sydney metropolitan areas

The Sydney basin region experiences some high ozone episodes in summer, especially in the north west and south west of Sydney. Observation-based methods can be used to provide a means to access the potential extent of photochemical smog problem at various regions in the Sydney area. In this study, the observation-based Integrated Empirical Rates (IER) model is used to determine and understand the photochemical smog at various sites in Sydney using ambient measurements at the monitoring stations. Using the 1998/1999 summer air quality data, clustering and principal component analysis methods are then applied to delineate the various regions in the Sydney basin based on the extent of photochemical reaction and the ozone concentrations. This will help in determining and classifying the various regions having different photochemical characteristics, from which appropriate control policy may be used to reduce the photochemical smog.