天津武清能见度特征分析

Analysis on the Characteristics of Visibility in Wuqing,Tianjin

利用2006年8～9月的野外观测资料,分析了天津武清区晴天能见度的变化特征,并分析了能见度与细粒子(PM2.5)、大气污染物和大气相对湿度(RH)的相关性。结果表明:观测期内大气平均能见度为6.3km,低于4km的时间段占50%;日变化表现为日出前(北京时间5时)能见度最低,约为2.6km,下午15时最高,约为11.1km;不同大气相对湿度下能见度与大气中细颗粒物浓度相关性不同;污染气体浓度与能见度呈反相关关系,φ(SO2)、φ(NO2)、φ(NO)、φ(NH3)和φ(CO)越高,能见度越低。

The characteristic of visibility in Wuqing, Tianjin was analyzed by using the experiment data from August to September, 2006. The relationship between visibility and the fine particle （PM2.5）, atmosphere pollution, Relative Humidity （RH） was analyzed at the same time. The results indicate that the average visibility was 6.3 km during experiment, and there was half time which visibility was lower than 4 km. The lowest visibility appeared at 0500 LST, which was about 2.6 km, and the highest visibility appeared at 1500 LST, which was about 11.1 km. The relationship between visibility and PM2. 5 was different in different RH. The concentration of atmosphere pollution and visibility showed inverse correlation, which the concentration of SO2, NO2, NO, NH3 and CO was higher, the visibility was lower.