A Preliminary Investigation Of Interaction Between Ozone And Particulates In An Oceanic Temperate Climate

Abstract

Results from smog chamber studies indicate that some Ozone (03) loss occurs in the atmosphere through being adsorbed on the surface of particulate matter present in the atmosphere. However, the field measurements, which can provide better clues to what exactly happens in the real atmosphere is lacking. The present study is based on concurrent measurement of O 3 concentration, particulate concentration and meteorological data during summer and winter periods from three different sites in Auckland, New Zealand. Multivariate data analysis technique was used for quantification of the relationship between the two pollutants. Monitoring revealed that both O 3 and Coarse Particulate Matter (CPM) exhibit diurnal variation, while the Fine Particulate Matter (FPM) concentration does not show any distinct pattern with respect to the time of the day. FPM concentration is higher in winter and low in summer, while CPM follows a totally opposite seasonal pattern. There was a significant increase in the mass concentration of both pollutants (i.e. O 3 and particulates) when air mass passed over the Auckland city compared to its origin in the marine sector. It was found that the relationship between O 3 and particulate concentration varied among the three sites. Two of the sites (i.e. coastal and urban) showed no significant (positive or negative) relationship between ozone and particles (either FPM or CPM). For the third site (i.e. rural), it was found that CPM concentration played a significant role in determining variability in O 3 concentration. Potential reasons are suggested for this difference.