北京西南部地区大气污染分析

Relationship between Visibility and Air Pollution over Southwestern Beijing

近年来北京的气象特征、雾霾发生频次、能见度变化特征及特点受到越来越多的关注。利用北京西南地区代表站的能见度,通过回归分析、Mann-Kendall趋势分析突变检验方法等,对近34年能见度的变化特征及突变性进行了分析研究,发现平原地区和山区日平均能见度年际变化均呈下降趋势,季节变化以春冬季能见度较好,日变化显著,平原站年均能见度在1997年前后出现突变。结合常规地面观测要素进行了相关分析,发现能见度与湿度相关性最好。利用房山区环保局提供的2013年全年污染物浓度数据,分析能见度与污染指数的关系,发现在各污染因子中,PM2.5同能见度的相关性最好,SO2相关性最差,为今后污染治理提供参考依据。

In recent years,more and more attention is focused on the characteristic changes of weather in Beijing,the frequency of fog and haze,and the changes of visibility.In virtue of regression analysis and Mann-Kendall rank statistics,the trends and the abrupt variations of visibility are analyzed by using the data of manual air horizontal visibility at surface meteorological stations from 1980 to 2014in the southwestern Beijing.The annual mean values of visibility show decreasing trends at the stations of plain and mountain areas.The visibility is better in spring and winter,and the diurnal variation of visibility is significantly.The analysis results show that abrupt variations of the annual mean visibility in the plain areas appeared in 1997.There existed significant correlation between visibility and surface meteorological conditions and air pollutants,with the correlation between the humidity and visibility being the best.Using air pollution data published by the local authorities in 2013,the analysis of visibility and air pollutant concentration illustrates that the correlation between PM2.5and visibility is the best,while that between SO2 and visibility is the poorest.