浙北地区2018年初一次污染过程分析

Analysis of a Pollution Process in Northern Zhejiang at the Beginning of 2018

为了探讨大气环境污染过程中气象条件对污染过程的影响和污染物的来源,利用常规观测资料、地面自动站资料以及PM_(2.5)数据,同时使用Traj Stat模型分析浙北地区2018年1月25日~2月4日的一次污染输送过程,结果表明:污染物的来源以来自西北方向的远距离输入为主,高值主要集中在苏南、江苏安徽交界处、山东南部及中部和河南东部等地,冷空气持续扩散南下是污染过程的天气背景;稳定的大气层结,较小的风速不利于污染物的扩散。此次污染过程前期相对湿度和能见度数值较高,主要是雾的作用;中后期雾霾混合,以霾为主。2月2日以后又一次冷空气南下,风速持续增大,大气扩散能力不断增强,污染物浓度下降,能见度好转。本研究结果可为今后类似大气环境污染事件提供跨区域污染联防联控的理论依据。

In order to explore the influence of meteorological conditions on the pollution process and the source of pollutants,based on the conventional observation data,ground automatic station data and PM_(2.5) data,and used Traj Stat model to analyze a pollution transport process in northern Zhejiang from January 25 to February 4,2018.The results showed that the sources of pollutants were mainly long-distance input from the northwest.The high values were mainly concentrated in southern Jiangsu,the junction of Jiangsu and Anhui,southern and central Shandong and eastern Henan.The continuous diffusion of cold air southward was the weather background of the pollution process.Stable atmospheric structure and low wind speed was not conducive to the diffusion of pollutants.The relative humidity and visibility were relatively high in the early stage of the pollution process,mainly due to fog;Fog and haze mix together in the middle and later stage,and mainly haze.After February 2,the cold air moved southward again,the wind speed continued to increase,the atmospheric diffusion capacity continued to increase,the concentration of pollutants decreased,and the visibility improved.The results of this study can provide a theoretical basis for cross-regional pollution prevention and control of similar pollution events in the future.