Observational Studies of Concentration Distributions of Atmospheric Fine Particles during Winter in the North Suburban Area of Nanjing

Atmospheric fine particles and boundary layer meteorological elements were observed in December, 2007,at the north suburban of Nanjing. The physical characteristics of fine particles, including diurnal variation of number concentration, size distribution, and the relations with meteorological factors were analyzed. The results show that aerosol pollution is serious in this region; the deterioration of visibility has close correlation with fine particles. The concentration diurnal variation showed a two peak pattern; the accumulation mode particles dominate surface concentration distributions; and fine particles increase during hazy periods. It is also indicated that, the meteorological conditions play a critical role in formation of fog and haze; lower relative humidity, weaker temperature inversion, and higher mixed height in haze periods than that in fog periods, can be quite useful to haze forecasting.