Variation of Visibility in Hangzhou Urban and Their Relation with Major Factors
Hong Shengmao 1, Jiao Li 1, He Xi 1, Bao Zhen 1, Sun Hongliang 1, Xu Hong 1, Ma Wanli 2, Yang Le 1, He Jiping 1 (1. Hangzhou Environmental Monitoring Center Station, Hangzhou 310007; 2. Hangzhou Environmental Meteorological Center, Hangzhou 310008,China)
Based on the study and monitoring of visibility and major air pollutants in Hangzhou City,the major causes of the decrease of visibility were discussed in urban area. The results showed that the visibility decreased significantly, the average values of visibility was about 10 km in 1980s,and about 7 km in first this centure. The major weather phenomenon in the lower visibility was haze. The seasonal variation of visibility was very obvious,it was best in summer and worst in winter. The visibility was decreased when the pollutants and relative humidity increased. The results of the multiple regression analysis between the visibility and pollutants and meteorological factors demonstrated that the relative humidity,NO2,aerosol particles PM2.5 were the three major factors which affected the visibility of Hangzhou urban area.
【CateGory Index】： X513