文章基本信息

标题：Impacts of COVID-19 on Air Quality in India
本地全文：下载
作者：Ram Lal Verma ; Jatinder Singh Kamyotra
期刊名称：Aerosol and Air Quality Research
印刷版ISSN：1680-8584
出版年度：2021
卷号：21
期号：4
页码：1-19
DOI：10.4209/aaqr.200482
语种：English
出版社：Chinese Association for Aerosol Research in Taiwan
摘要：The COVID-19 pandemic spread all over the world in early 2020. India imposed a nationwidelockdown on March 25, 2020, for more than a month to contain the COVID-19 infection. Duringthe nationwide lockdown, transport, industries, and commercial activities were suspended, exceptfor essential services. We made a detailed analysis of the impacts of COVID-19 on air quality inIndia by using the data from more than 200 Continuous Ambient Air Quality Monitoring Stations(CAAQMS) and reported a change in the National Air Quality Index (NAQI), spatial distributionand concentration levels of PM10, PM2.5, CO, NO2, SO2, and O3 from January to April 2020 nationwideand in five major cities, namely, Delhi, Mumbai, Kolkata, Chennai, and Hyderabad. We defined theperiod between February 25 to March 24, 2020, as ‘before lockdown’ and March 25 to April 30,2020, as ‘during lockdown’. The NAQI and satellite visual maps of AOD, NO2, CO, and SO2 fromJanuary to April 2020 showed a significant decrease in air pollution levels in India. The averageconcentration levels of PM10, PM2.5, CO, NO2, and SO2 have decreased nationwide by 33, 34, 21,47, and 21%, respectively, during the nationwide lockdown compared to their concentrationlevels before the lockdown. While comparing their concentration levels of the nationwidelockdown period with those observed in April 2019 at the same CAAQMS, it was found that thenationwide average concentration levels of PM10, PM2.5, CO, NO2, and SO2 were decreased by 53,45, 27, 54, and 35%, respectively. The trends of decreasing air pollutants during the lockdown infive major cities were almost the same as nationwide. The concentration levels of O3 have shownan increasing trend from January–April 2020 including during the nationwide lockdown. TheCOVID-19 has provided a rare opportunity for India for the collection of air pollution baselinedata which could be useful in the formulation of air pollution reduction policies in the future.
关键词：Air quality;Lockdown;COVID-19;Air quality index;Particulate matters