摘要
对污染天气的污染过程及成因进行研究分析,有利于提高污染天气预警预报精准度及污染源管控效率。本文针对贵阳市2023年1月31日-2月1日一次PM_(2.5)污染过程(污染期间AQI分别为104和115),利用反距离权重插值、WRF-Chem数值模拟、卫星遥感监测和在线源解析等手段,从气象条件、本地污染源排放和区域传输叠加等方面进行分析。结果表明,此次污染过程污染期间的PM2.5浓度较污染前期增幅43.5%,污染结束的PM_(2.5)浓度较污染期间降幅64.0%,另外,污染期间贵阳市PM_(2.5)与PM_(10)、SO_(2)、NO_(2)、CO的波动变化高度一致,各区(县、市)PM2.5浓度整体都较高,此次污染事件为大范围的区域污染事件;此次污染过程前期及污染期间昼夜温差较大,夜间降温后近地面形成辐射逆温,不利于PM_(2.5)扩散稀释,个别时段边界层高度与PM_(2.5)质量浓度呈同步增降,且当边界层高度位于600米以下时容易出现PM_(2.5)高值;从排放源来看,污染期间二次无机源、机动车尾气排放和生物质燃烧源较非污染日的贡献占比都有增加;整体来看,本次污染成因主要是由于机动车尾气、生物质燃烧等本地污染源排放,加上贵阳市上风向森林火灾等区域传输叠加共同作用造成的。
Studying the pollution process and causes of polluted weather helped improving the accuracy of pollution weather warning and prediction,as well as the efficiency of pollution source control.This article focuses on a PM_(2.5)pollution process in Guiyang City from January 31 to February 1,2023(with AQI of 104 and 115 respectively during the pollution period).Using methods such as inverse distance weight interpolation,WRF-Chem numerical simulation,satellite remote sensing monitoring,and online source analysis,the analysis is conducted from meteorological conditions,local pollution source emissions,and regional transmission superposition.The results showed that the concentration of PM_(2.5)during the pollution process increased by 43.5%compared to the pre pollution period, and the concentration of PM 2.5 at the end of the pollution decreased by 64.0% compared to the pollution period. In addition, the fluctuation and changes of PM_(2.5)and PM_(10) , SO_(2), NO_(2), CO in Guiyang City during the pollution period were highly consistent, and the PM_(2.5)concentration in each district (county, city) was generally high. This pollution event is a large-scale regional pollution event;the temperature difference between day and night is large in the early stage of the pollution process and during the pollution period. Radiation inversion is formed near the ground after the temperature drops at night, which is not conducive to the diffusion and dilution of PM 2.5 . In some periods, the height of the boundary layer and the PM_(2.5)mass concentration increase and decrease synchronously, and when the boundary layer height is below 600 meters, it is easy to have a high value of PM_(2.5);from the perspective of emission sources, the contributions of secondary inorganic sources, motor vehicle exhaust emissions, and biomass combustion sources have all increased during the pollution period compared to non pollution days;overall, the main cause of this pollution is due to the combined effects of local pollution sources such as motor veh
作者
焦树友
王琴
石宇
陈远航
李光一
张会
Jiao Shuyou;Wang Qin;Shi Yu;Chen Yuanhang;Li Guangyi;Zhang Hui(Guiyang Ecological Environment Bureau;Guiyang Energy Conservation Monitoring Station;Guiyang Ambient Air Quality Forecasting and Forecast Center;Guizhou Chuyun Environmental Protection Technology Co.,Ltd;Guizhou Ecological Meteorological and Satellite Remote Sensing Center,Guiyang 550002;Guangzhou Hexin Instrument Co.,Ltd.,Guangzhou 510000)
出处
《环保科技》
2023年第3期38-45,共8页
Environmental Protection and Technology
关键词
PM2.5
污染过程
本地排放
区域传输
贵阳市
PM_(2.5)
pollution process
local emissions
regional transmission
Guiyang
