一次非典型颗粒物与臭氧同时污染过程分析

An analysis on atypical particulate and ozone pollution process

本文针对首次在常州地区夜里出现颗粒物及臭氧同时异常升高的污染过程,从污染物变化特征、气象场、后向轨迹、超级灰霾站监测数据和多组分因子逐步深入分析,较为全面客观揭示了该次污染过程成因,有以下四方面:(1)常州及周边地区当天均发生了区域性雷暴天气,有可能产生高浓度臭氧和大量二次颗粒物,(2)先低压气旋后冷锋过境气象场使得气团汇聚和堆积,(3)初夏雨止过后夜里边界层降低及高温高湿环境进一步促进污染物浓度上升,(4)南方较高浓度的硝酸根和重金属气团为该次污染过程提供了充足的二次污染前体物,四方面原因导致了该次在常州地区发生的较为非典型污染天气过程。

In order to make clear the reason behind the process where particular matter and ozone ab-normally went up at night and was observed for the first time in Changzhou City, this paper presents the results from a step by step in - depth analysis in terms of the variation characteristics of pollu-tants ,meteorological field, backward trajectory and super haze station data. And the reasons behind this pollution process is obtained and summarized as follow ： （ 1） thunderstorm weather having taken place in Changzhou and surrounding areas on that day may produce high concentrations of ozone and large number of secondary particles, （2） low pressure prior to the cold front created the condition for air mass convergence and accumulation, （ 3 ） lowering boundary layer due to rain in early summer to-gether with high temperature and high humidity environment at night promoted further the rise of pol-lutants concentration, （4） high concentrations of nitrates and heavy metals in southern City provided enough precursors for secondary pollution.