Inter-Relationships and Seasonal Variations of Inorganic Components of Pm10 in a Western Pacific Coastal City

Five year (1995–1999) datasets for inorganic major and trace components in PM₁₀ from three monitoring sites in Hong Kong are presented. The concentrations of most chemical constituents show a high degree of seasonality, with high concentrations in winter but low ones in summer, resulting from the combined effects of summer monsoon scavenging and the influx of the continental air mass of the winter monsoon. High correlations exist within crustal components, as well as within sea-salt components. Non-seasalt sulphate and ammonium ion contributions to the PM₁₀ mass are similar at all sites and are greatest in the winter months, showing the importance of non-local contributions. The concentrations of chemical components in PM₁₀ from this study are compared with those in wet deposition in Hong Kong, as well as with PM₁₀ results from other countries. In general, the Asian countries experience more elevated concentrations of PM₁₀.