2013-2016年浙北城市群空气质量变化特征及与气象条件的关系分析

Variation Characteristics of Air Quality and Its Relationship with Meteorological Factors from 2013 to 2016 in the Northern Urban Agglomerations of Zhejiang Province

利用2013-2016年浙北城市群逐日空气质量日报数据,对空气质量指数(AQI)、首要污染物及各污染物浓度的特征变化进行研究,结合气象资料探讨降水、风速、逆温等气象条件对空气质量变化的影响。结果表明:(1)在2013-2016年期间,浙北城市群AQI整体呈逐年减小趋势,季节AQI差异减小趋势明显,年内除夏季外,春季、秋季和冬季AQI均逐年减小;(2)以PM2.5为首要污染物的污染天数有所减少,而以O3为首要污染物的污染天数增加明显,光化学污染成为浙北城市群越来越重要的污染形式。(3)PM2.5、PM10、CO、SO2和NO2平均质量浓度在不同季节均有所下降,O3平均质量浓度较为稳定,且各城市质量浓度变化趋势不一致。(4)年降水日数增多和春季、秋季和冬季边界层逆温频率减少是PM2.5、PM10、CO、SO2和NO2质量浓度减少的重要原因之一。(5)浙北城市群政府采取的一系列防治大气污染的措施,使得浙北城市群除O3外的污染物排放量得到有效控制。

Based on the daily air quality report in 2013 to 2016 in the northern urban agglomerations of Zhejiang province,the variation characteristics of air quality index(AQI),primary pollutant and concentration of air pollutants were analyzed,and the influence of meteorological conditions such as precipitation,wind speed and temperature inversion on the change of air quality were discussed.The results as follows:1)the air quality index had a decreasing tendency in the northern urban agglomerations of Zhejiang province during the 2013-2016 period,and the seasonal variation of the air quality index decreased.In addition to summer,the AQI in spring,autumn and winter is decreasing year by year.2)pollution days with PM2.5 as the primary pollutant decreased,and pollution days with O3 as the primary pollutant increased obvious.3)the average mass concentration of PM2.5,PM10,CO,SO2 and NO2 decreased in different seasons,but the average mass concentration of O3 was stable,and the change trend of quality concentration of O3 in different cities is inconsistent.4)the increase of annual precipitation and the decrease of boundary layer inversion in spring,autumn and winter is one of the important reasons for the decrease of the mass concentration of PM2.5,PM10,CO,SO2 and NO2.5)A series of measures to prevent and control air pollution by the government of the northern Zhejiang urban agglomeration have effectively controlled the pollutant discharge except O3.