新冠病毒肺炎疫情防控期间信阳市中心城区空气质量变化

Variations of Air Quality in the Central City of Xinyang During the Period of COVID-19 Pneumonia Contagion Prevention and Control

基于信阳市中心城区的空气质量指数(AQI)日均值和《环境空气质量标准》(GB3095-2012),着重调查研究了该城区2020年1月21日-3月25日新冠病毒肺炎疫情防控相对严格期间的环境空气质量变化.结果表明:此期间该城区除了1 d重度、3 d中度、11 d轻度污染天气外,没有严重污染天气,空气质量是2016年以来历年同时段最好的,疫情防控使环境空气质量总体上改善显著;环境空气质量存在震荡性变化;空气污染多发生于多云、阴、小雨、风力≤2级并挟带颗粒污染物质的北或偏北风天气条件下,颗粒物特别是PM 2.5为主要污染物质,O 3潜在污染问题突出;疫情防控力度对空气质量变化影响明显,疫控较严时没有出现中、重度污染天气,但仍出现了轻度污染天气,提示未来该城区乃至我国类似城市地区进一步改善环境空气质量可能面临着颗粒物特别是PM 2.5和O 3控制的艰巨性和复杂性问题.

Based on“Ambient air quality standards”(GB3095-2012)and the daily air quality index(AQI)from Jan.21 to Mar.25 of 2020 being in the strict period of COVID-19 pneumonia contagion prevention and control in the central city of Xinyang of Henan province,China,the daily changes of ambient air quality was investigated.The results showed:there was no severe air pollution day occurred except 11 light,3 middle and 1 heavy pollution days,which indicated that the ambient air quality in this city in this period was greatly improved and became the best compared with the same historical period since 2016.However,ambient air quality showed its temporal oscillation.Pollution days in this period happened easily under weather conditions such as cloudy,overcast sky,drizzle,flurry and the north or northerly wind not higher than breeze but carrying air particle pollutants.Particulates,PM 2.5 in particular,were the primary air pollutants,and ozone still showed its potential pollution in this period as before.The contagion prevention and control measures had an significant influence on the air quality,and neither middle nor heavy pollution day occurred under stringent measures,but a few light pollution days happened as well.All the above suggest that the particle pollutants,especially PM 2.5,as well as O 3 might be the formidable challenges in the future to this city or even the akin cities in China being dedicated to a better ambient air quality.