Lockdown Effect on Air Pollution: COVID-19

India is 21 of the world's 30 most polluted cities but recently, Air pollution levels have started to drop dramatically as the second most populated nation endures the second week of a 21 days Lockdown amidst corona virus fears. While the complete shutdown of India's economy was designed to stop the spread of COVID-19. It is having a health benefit of clearing the air that millions of people were choking on. As vehicles stay off the road, construction is put on hold, and factories stop production, the levels of microscopic particulate matter helps air pollution to start to drop. It is true that pollution levels are going down and will continue to be lower as a result of Lockdown.

Recent heavy rains in the north and west of the country have also helped the country's pollution levels. Rain is a very effective aerosol removal process from the atmosphere and can bring down particulate matter values. Since the March 25 Lockdown that forced 1.3 billion Indians to stay home. Air quality in New Delhi, usually the worst in the world has dropped to satisfactory levels. The Lockdown order shut down offices, schools, movie theaters, malls, markets and non-essential service providers. All modes of public transport such as metro trains, buses, inter-state trains and domestic and international flights for civilian movement have also been stopped.

The effect of the Lockdown has been dramatic. In New Delhi, where flights have been diverted because smog shrouded the airport. The air pollution levels have dropped 71 percent in just one week. On March 20, the air had an unhealthy 91 Micrograms per cubic meter of PM 2.5. On March 27, Just a couple days into the Lockdown that level fell to 26 micrograms per cubic meter. Anything above 25 is considered unsafe.

We have not seen such blue skies in Delhi for the past 10 years. It is a silver lining in terms of this awful crisis that we can step outside and breathe fresh air. The air quality is likely to slip into good category soon. It is due to reduced vehicular traffic and rise in temperature. However, It is important to remember that this is a temporary reprieve that will return if industry and vehicular traffic return once the Lockdown is over. As for its effect on the climate crisis. Efforts to control the corona virus pandemic have reduced economic activity and led to localized improvements in the air quality. But it is too early to assess the implications for concentrations of greenhouse gases which are responsible for long-term climate change.