蒋荣 钱震 陈帅

摘要：结合南通市空气自动站、大气超级站、气象台的多种在线仪器设备逐时监测数据，对南通市冬季一次典型重污染过程成因及特征进行了分析。结果表明，外来输入和本地聚集的污染物，在高压控制、大气静稳的天气形势下，难以扩散，导致了本次重污染过程。本次污染以细小颗粒物为主，粒径小于2.5μm的颗粒物占总和的99.99%。首要污染物PM2.5中总碳（TC）浓度占9%～21%，TC/ PM2.5浓度占比与PM2.5浓度变化趋势一致。有机碳/元素碳（OC/EC）的比值表明，此次重污染过程存在二次有机碳污染，污染物主要来源于柴油和汽油车尾气排放以及燃煤排放。

关键词：重污染;粒径分布;有机碳/元素碳;PM2.5

中图分类号：X831    文献标识码：A    文章编号：2095-672X（2021）01-0083-05

DOI.10.16647/j.cnki.cn15-1369/X.2021.01.013

Study on the causes and characteristics of a typical heavy air pollution process in Nantong

Jiang Rong， Qian Zhen，Chen Shuai

（Nantong Environmental Monitoring Center，Nantong Jiangsu 226006，China）

Abstract：The causes and characteristics of a typical heavy air pollution process in winter in Nantong were analyzed based on the hourly monitoring data of various On-line monitoring instrument from air automatic station， atmospheric super station and meteorological observatory. Results showed that the heavy air pollution process was the result of the fact that imported and locally gathered pollutants difficult to diffuse under the weather conditions of high pressure control and stable atmosphere. The pollution was dominated by fine particles with particle size less than 2.5 um accounting for 99.99% of the total. In PM2.5， the total carbon （TC） concentration accounts for 9%～21%， and the proportion of TC/ PM2.5 is consistent with the change trend of PM2.5 concentration. The OC/EC ratio indicated that there was secondary organic carbon pollution in this heavy air pollution process. The pollutants mainly came from diesel and gasoline vehicle exhaust emissions and coal burning emissions.

Key words：Heavy air pollution; Particle size distribution; Organic Carbon（OC）/Elemental Carbon（EC）; PM2.5

自“霧霾”一词成为2013年度关键词以来，重污染天气一直备受领导及市民的高度关注。虽然已有大量人力物力财力的投入，我国大气污染防治形势依然非常严峻，2016年东北10城AQI值爆表事件，又一次将重污染天气话题推向风口浪尖。重污染天气不仅会导致高速公路封闭、航班延误等，还危害公众健康。因此，开展重污染天气研究对经济和社会发展、气候与环境变化、人体健康和区域和谐发展等具有重要的现实意义[1]。

针对我国近年频发的重污染天气，诸多学者已从多角度开展了相关研究。周敏等[2]研究了重污染期间上海市细颗粒物化学组分特征及污染来源类型。喻义勇等[3]对南京市一次持续重污染天气特征及成因进行了分析。徐曼等[4]分析了石家庄市冬季典型重污染天气演变过程。……