Abstract

This discussion paper looks into the COVID-19 induced lockdown on the air quality of the five most polluted cities in India. There were significant reductions in the concentrations of particulate matter, ≤ 2.5 µm and ≤ 10 µm, NO₂, and CO during lockdown compared to that in 2019. Even then, the levels of particulate matter never reached the target specified by the World Health Organization. There was an increase in the concentrations of O₃ at some cities, which may be attributed to the alterations in the photo-stationary cycle due to change in the concentration of nitrogen oxides and volatile organic carbons.

中文翻译：

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COVID-19大流行封锁导致印度五个主要城市的空气质量

摘要

这份讨论文件调查了COVID-19导致的印度五个污染最严重城市的空气质量封锁。与2019年相比，锁定期间的颗粒物，≤2.5 µm和≤10 µm，NO ₂和CO的浓度显着降低。即使那样，颗粒物的水平也从未达到世界卫生组织指定的目标。在某些城市中，O ₃的浓度有所增加，这可能归因于氮氧化物和挥发性有机碳浓度的变化导致的光平稳周期的变化。