July , 2020
Lockdown has reduced air pollution, world must act to sustain it
17:45 pm

Tushar K. Mahanti

The world had not seen such clear blue skies for years. Global lockdowns dramatically reduced air pollution across countries, erasing the haze that covered the sky. Maybe, the reduction in air pollution due to lockdowns is a temporary phenomenon and when the world comes back to its regular schedule, the quality of air would deteriorate again. But it has opened up a possibility that given the proper implementation of long-term ambitious policies and forward-looking investments, air pollution can be checked.


The coronavirus pandemic is the most urgent threat facing humanity but climate change is the biggest threat that the world has been facing over a long time, said the UN Climate Change Executive Secretary, Patricia Espinosa. Carbon dioxide remains in the atmosphere and oceans for centuries, causing serious health hazards for human beings. Carbon dioxide, a by-product of fossil fuel combustion is the principal greenhouse gas contributor to global warming.


The average global land and ocean surface temperature for March 2020 was 1.16°C (2.09°F) above the 20th century average of 12.7°C (54.9°F) and the second highest in the 141-year record. The rise in global temperature and in turn, climatic changes have a huge impact on the environment. The World Meteorological Organisation report titled ‘State of Global Climate in 2019’, published early March, 2020 shows that increasing land and ocean heat, accelerating sea level rise and melting ice are having a major effect on all aspects of the environment, as well as on the health and well-being of the global population.


Earlier, the Global Environment Outlook (GEO) 2019 of the UN had stated that damage to the planet is so dire during this period that people’s health will be increasingly threatened unless urgent action is taken. The report suggests that about a fourth of all premature deaths and diseases worldwide are due to manmade pollution and environmental damages. It warns that deadly emissions, chemicals polluting drinking water, and the accelerating destruction of ecosystems rucial to the livelihoods of billions of people are driving a worldwide epidemic that will hamper the global economy.


Association between pollution and COVID-19

It’s probably early to have any definite scientific assessment of the relationship between air pollution and the spread of Covid-19. Environmental and meteorological factors have been linked to various diseases, including severe acute respiratory syndrome (SARS) and the Middle East Respiratory Syndrome (MERS).

Based on these findings, Yongjian Zhu’s study titled, “Association between short-term exposure to air pollution and COVID-19 infection: Evidence from China” published in Science of The Total Environment (2020) tried to explore the relationship between ambient air pollutants and the infection caused by Covid-19.

The study collected data of daily confirmed cases, airpollution concentration and meteorological variables in 120 cities in China from January 23, 2020 to February 29, 2020. It applied a generalised additive model to investigate the associations of six air pollutants (PM2.5, PM10, SO2, CO, NO2 and O3) with Covid-19 confirmed cases. The study found significantly positive associations of PM2.5, PM10, NO2 and O3 in the last two weeks with new Covid-19 confirmed cases. Results indicate that there is a significant relationship between air pollution and Covid-19 infection, which could partially explain the effect of the national lockdown and provide clues for the control and prevention of this novel disease.

Government scientists in the US estimate that Covid-19 may kill up to 2.4 lakhs Americans. The majority of the pre-existing conditions that increase the risk of death for Covid-19 are the same diseases that are affected by long-term exposure to air pollution. A study by Xiao Wu, Rachel C. Nethery, Benjamin M. Sabath, Danielle Braun, and Francesca Dominici titled, “Exposure to air pollution and COVID-19 mortality in the United States”, based on data collected for about 3000 counties in the US up to April 04, 2020, finds that the small increase in long-term exposure to PM2.5 leads to a large increase in Covid-19 death rate. An increase of only 1 μg/m3 in PM2.5 is associated with a 15% increase in the Covid-19 death rate. Studies on the correlation between Covid-19 lethality and the atmospheric pollution in northern Italy found that people living in areas with high levels of pollutants are more prone to develop chronic respiratory conditions and suitable to any infectious agent. A prolonged exposure to air pollution leads to a chronic inflammatory stimulus and the high level of pollution in northern Italy should be considered an additional co-factor of the high level of lethality that the Covid-19 pandemic recorded in that area.

Understandably, the above studies are based on shorter time frames and smaller samples and thus, it may be premature to identify poor air quality as the sole cause of the spread of Covid-19 pandemic. But what can be said based on these studies is that poor air quality may be a factor to consider on the spread of Covid-19. After all, according to the World Health Organisation, 4.6 million individuals die annually from diseases and illnesses directly related to poor air quality.


Levels of two major air pollutants drastically reduced globally during the lockdown. Two new studies, published in the journal, Geophysical Research Letters, found that nitrogen dioxide pollution over northern China, western Europe and the US declined by as much as 60% in early 2020 as compared to the same time of the previous year.


One of the studies also found that particulate matter pollution – particles smaller than 2.5 microns – decreased by 35% in northern China. According to Jenny Stavrakou, an atmospheric scientist at the Royal Belgian Institute for Space Aeronomy in Belgium and co-author of one of the research papers, such a significant drop in emissions is unprecedented since air quality monitoring from satellites began in the 1990s.


They found that nitrogen dioxide pollution decreased by an average of 40% over Chinese cities and by 20% and 38% over western Europe and the US during the 2020 lockdown, as compared to the same time in 2019.


By March, the decline in coal use by power plants, oil refining, steel manufacturing and air travel was estimated to have caused a 250 Mt decrease in CO2 emissions. NASA and the European Space Agency reported a dramatic fall in N2O pollution across north-eastern China and the lowest average level of N2O ever recorded in India was a result of the nationwide curfew at the end of March.


The fear that infection from the novel coronavirus can lethally impair lungs and breathing has forced people into prolonged inactivity and considerably improved the air quality of the cities. The International Energy Agency (IEA) has estimated that global energy-related CO2 emissions are set to fall by 8% this year — the largest decrease in emissions ever recorded and six times the previous record drop of 400 million tonnes in 2009 that occurred after the financial crisis.

Indian experience

The environmental website, Carbon Brief, says India’s emissions fell by 1.4% in FY20 (Lockdown began on March 24). During that month, it says, CO2 emissions dropped by


In Delhi, the AQI was ‘satisfactory’ for 18 days in April and May compared to just one day during the same period last year. ‘Satisfactory’, is one step lower than ‘good’ in the six rung AQI. One step lower than ‘satisfactory’ is ‘moderate’ and there were 41 such days compared to 26 in the year-ago period. Thirty-four days were ‘poor’ or ‘very poor’ during April-May 2019 as against two ‘poor’ days during the same period this year.

Based on data from satellite imagery from the European Space Agency’s Copernicus 5P, researchers find that pollution levels dropped most dramatically in Delhi’s metropolitan area. NO2 levels from March 25 to May 2, 2020 averaged 90 upmol / m2 compared to 162 from March 1 to March 24, 2019; NO2 levels from March 25 to May 2 were also far above this year’s 158 upmol / m2.

In Greater Mumbai and Navi Mumbai, a similar trend was observed as NO2 levels from March 25 to May 2, 2020 averaged 77 μmol /m2 compared to 117 μmol/ m2 from March 1 to March 24. In 2019, NO2 levels from March 25 to May 2 averaged 122 μmol /m2. In nearly all other big Indian cities, similar drops in NO2 levels are apparent.

The lockdown improved the air quality index to ‘satisfactory’ levels in nearly 95% of the 105 cities monitored by the country’s Central Pollution Control Board on July 16. Air quality in 48 of these cities were declared good and only five cities reported moderate air quality.


Bengaluru Delhi Chennai Hyderabad Mumbai Kolkata The air quality index in March and April 2020 over the same period last year has declined sharply in major Indian cities indicating an improvement in air quality. India’s IT hub Bengaluru has witnessed a sharp improvement in air quality during this period with 51% fall in the AQI. According to the Karnataka State Pollution Control Board, there was a 60 to 65% pollution reduction during the early days of lockdown. The clean air, however, has come at a cost and is likely to be short-lived. India is slowly getting its factories open and businesses are opening after the lockdown.

Economic opportunity for India

As a result of the rapidly spreading virus, economic growth across the world is feared to decelerate in 2020. The International Monetary Fund (IMF), the Organization for Economic Cooperation and Development (OECD), and The World Bank have all revised their forecasts downward between late 2019 and mid-20, reflecting the rapidly deteriorating state of the global economy. The IMF projected the global growth at 4.9% in 2020, 1.9 percentage points below the April 2020 World Economic Outlook (WEO) forecast.

According to the IMF, India's economy is projected to shrink by 4.5% in the current fiscal due to the lockdown. International rating agencies like Moody's Investors Service, Fitch Rating and S&P Global Ratings have all predicted a 4-5% contractionin India's economic growth in 2020-21.


Amidst the bad news, India still has reasons to look forward. India gets a rare chance to take a centre-stage in the world manufacturing economy. The world has seen the risk of sourcing manufactured produce from one country – China. Such concentration may provide cheap goods but over-dependence on one source may be very expensive and dangerous when the system breaks down. This may lead to the emergence of multiple manufacturing hubs. This may provide India with a great advantage.


The public health system has become a big issue during the pandemic throughout the world. India could be a major manufacturing base for vaccines and it could provide facilities and training for many developing countries and establish R&D for early detection and monitoring of such future situations. The large pharmaceutical base will also help and gain in that process.

The Covid-19 pandemic has given India a rare chance to reinvent agriculture. In times of crisis, social stability is of great importance and that is secured with production and distribution of food grains. For the next one year, until the economy starts recovering, at least there will be food for everyone – a great solace for policy makers. India needs to refocus on the agriculture sector after Covid-19 pandemic, but in different directions. The government must streamline the marketing of agricultural products and focus on value addition and rural agro-processing industries.


But whether it is to expand manufacturing base or to focus on agricultural growth, environmental compliance must be at the core.


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