Abstract: The relationships among monthly average concentrations of air pollutants (SO2, NO2 and PM10) over Urumqi and the monthly coal consumption, inversion layer thickness and monthly average wind speed were investigated. It was found that coal consumption and inversion layer thickness were the dominant factors affecting the diffusion of air pollutants over Urumqi. Based on these analyses, the regression models were developed to describe the effects of coal consumption, inversion layer thickness and wind speed on the concentrations of air pollutants. It was concluded that the effect of inversion layer thickness on different pollutants was different, and wind speed played more important role in diffusion of air pollutants during heating period than during nonheating period.

Key words: air pollutant, quantitative model, inversion layer, coal consumption, Urumqi