Abstract

The coronavirus disease 2019 (COVID-19) pandemic, caused by the new coronavirus SARS-CoV-2, struck India on January 30,
2020, in Kerala, with the first positive case, forcing a 4-month nation-wide lockdown from March 25 to May 31, 2020, followed
by a period of unlocking. Unfortunately, in the month of March 2021, India was hit by a major second wave of the COVID-19
pandemic, prompting a state-wide lockdown. Lockdown was a curse for India’s 1.39 billion people, yet it was a blessing for
the environment. Because of the disastrous spread of coronavirus and consequent shutdown, many manmade activities were
halted, allowing the ecosystem to flourish. The present article highlights the impacts of both the lockdowns on ambient air
quality of Lucknow, Capital city of most polluted state in India. Air quality index (AQI) values for four hazardous air pollutants
(particulate matter2.5 [PM2.5], NO2, SO2, and CO) were monitored and evaluated in the Lalbagh area of Lucknow during various
phases of 1st and 2nd lockdown and the AQI value of PM2.5 were further converted into concentration term (μg/m3) to analyze a
24 h average variation. The lowest concentration of PM2.5 was measured at 41.5 μg/m3 during the first lockdown and 11.5 μg/m3
during the second lockdown, resulting in a reduction in levels of PM2.5. During the first lockdown, the highest and lowest
recorded AQI values for gaseous pollutants, namely, NO2, SO2, and CO, were 35, 3, 10 and 0, 1 and 5, while during the second
lockdown, the highest and lowest recorded AQI values were 30, 9, 20 and 20, 1,and 5, respectively. Explanatory explanations
for the positive influence of meteorological discoveries in enhancing air quality during 1st lockdown and 2nd lockdown are also
established in this study.