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Author: Tuhin Bhadra & Kasturi Mukherjee

#PositiveCorona: Impact of COVID-19 Lockdown on the Air Quality of Three Megacities in India

Introduction: The megacities all over the world are vulnerable to air pollution with the rapidly increasing population and economic developmental activities. Uncontrolled urban growth and unplanned industrialization and automation play a key role to deteriorate the quality of air in the megacities of developing countries.  Delhi, Mumbai and Kolkata are three populous megacities in India which face the serious problem of air pollution. Air pollution can broadly be classified into two categories, i.e. (i) Visible air pollution and (2) Invisible air pollution. The smog is an example of visible pollution whereas the good examples of invisible air pollutant are Sulfur dioxide (SO2), Carbon monoxide (CO), Nitrogen dioxide (NO2), Volatile Organic Compound (VOCs), Ozone (O3), Particulates (PM 2.5, PM 10), Chlorofluorocarbons (CFCs), Lead and heavy metals, Unburned hydrogen carbon, Gaseous ammonia (NH3) etc. While all pollutants in the atmosphere cause harm to the planet there are some that are more dangerous than others. These dangerous air pollutants are PM 2.5, PM 10, NO2, NH3, SO2, CO, O3. The concentration of these pollutants is regularly monitored by the Central Pollution Control Board (CPCB) to assess air quality in different locations in India.

A nationwide lockdown was imposed in India from 24th March to 31st May 2020 to prevent the spread of COVID-19. Due to this lockdown, all industrial activities, public transport, and other economic and developmental activities were stopped, which played an important role to reduce the pollution level in the cities across the country. The air quality of Delhi, Mumbai and Kolkata also changed considerably from the pre-lockdown condition to the lockdown period. In the present study, the air quality parameters of these megacities in January (Pre-Lockdown) and April (During-Lockdown) have been studied from the CPCB data to understand the role of COVID-19 Lockdown on the air quality of these cities. Changing the concentration of the major pollutants have been discussed in the following section.

Particulates: Particle pollution -also called particulates matter (PM)-is made up of particles (tiny pieces) of liquid or solid that are in the air. Particulate matter can be released from different types of human activities such as vehicle emissions, smoke particles, dust particles, and ash from industries. The PM 10 is particulate matter 10 micrometers or less in diameter whereas, the PM 2.5 is particulate matter 2.5 micrometers or less in diameter. PM 2.5 is generally described as fine particles. During the Pre-Lockdown normal condition, the PM 2.5 concentration in air in Delhi, Mumbai, and Kolkata were 436 µg/m3, 236 µg/m3 and 246 µg/m3 respectively. Whereas, during the lockdown, the concentration of PM 2.5 in these three megacities became 89 µg/m3, 31 µg/m3 and 78 µg/m3. Similarly, PM 10 concentration during the pre-lockdown period were 334 µg/m3, 220 µg/m3 and 225 µg/m3, which dropped below 56 µg/m3, 70 µg/m3 and 81 µg/m3 during the lockdown.

Nitrogen dioxide and Ammonia: Combustion of fossil fuels (coal, gas, and oil) especially fuel used in cars is the main source of nitrogen dioxide resulting from human activities. The Ammonia (NH3) is a colourless gas which combines in the atmosphere with sulphate and nitrates to form secondary fine particulate matter (PM 2.5). During the Pre-Lockdown normal condition, the NO2 concentration in air in Delhi, Mumbai and Kolkata were 77 µg/m3, 92 µg/m3 and 76 µg/m3 respectively. Whereas, during the lockdown, the concentration of NO2 in these three megacities became 22 µg/m3, 14 µg/m3 and 31 µg/m3. Similarly, NH3 concentration during the pre-lockdown period Delhi, Mumbai and Kolkata were 7 µg/m3, 4 µg/m3 and 13 µg/m3, which dropped below 3 µg/m3, 3 µg/m3 and 8 µg/m3 during the lockdown.

Sulfur dioxide and Carbon monoxide: Fossil fuel combustion at power plants, other industries, and in mobile sources like locomotives, ships are the mail sources of Sulfur dioxide (SO2) emission. Harmful compounds, such as sulfuric acid, sulfurous acid and sulfate particles are formed from the reaction of SO2 with other substances. During the Pre-Lockdown normal condition, the SO2 concentration in air in Delhi, Mumbai and Kolkata were 11 µg/m3, 21 µg/m3 and 22 µg/m3 respectively, which became below 13 µg/m3, 4 µg/m3 and 18 µg/m3 during the lockdown. Carbon monoxide (CO) is a colourless, odorless gas that can be harmful when inhaled in large amounts. CO is released when something is burned. The greatest sources of CO in outdoor air are cars, trucks and other vehicles or machinery that burn fossil fuels. During the Pre-Lockdown normal condition, the CO concentration in air in Delhi, Mumbai and Kolkata were 121 mg/m3, 91 mg/m3 and 30 mg/m3 respectively, which became below 47 mg/m3, 17 mg/m3 and 14 mg/m3 during the lockdown.

Not Only air pollution, the water of the rivers is less polluted now than what they were for decades. This lockdown has reduced pollution and an improvement in all environmental indicators across these cities. The CPCB calculates Air Quality Index (AQI) to assess the air quality of any location-based on some air quality parameters (PM 2.5, PM 10, NO2, NH3, SO2, CO, O3).  AQI values are broadly classified into six categories, i.e. good (0 to 50), satisfactory (51 to 100), moderate (101 to 200), poor (201 to 300), very poor (301 to 400) and severe (401 to 500). According to CPCB, the AQI value in Delhi was 436 (severe) in January and became 89 (satisfactory) in April. During the Pre-Lockdown normal condition (January), the AQI values in Mumbai and Kolkata were 236 (poor) and 246 (poor) respectively, which changed to 70 (satisfactory) and 81 (satisfactory) during the Lockdown in April. The AQI values show, how the lockdown played a crucial role to purify the air of these megacities.  Among the selected pollutants, the maximum reduction of concentration was observed for PM10 and PM2.5 have reduced followed by NO2, CO. A negative trend was observed for SO2 in Delhi.

The environmental benefits of this lockdown are exactly what were required in these cities without any proactive mitigation measure. But stopping or slowing down the industrial activities impose a big question on the growth of economy. However we hope for a better dealing with pollution in post lockdown period.  

The Relevance of Deep Ecological Thoughts in the Perspective COVID-19

Human being has become that force of the ecosystem which is continuously shaping the earth. Human action has transformed between one third and half of the earth’s surface; the concentration of carbon dioxide in the atmosphere has enhanced by almost 30 percent since the onset of the industrial revolution. Humankind fixes more atmospheric nitrogen than all natural terrestrial sources considered. They use more than half of all available surface freshwater; and about one-quarter of Earth’s bird species have been forced to extinction. Simultaneously they are making growing efforts to reverse and to change the course of these trends. It had become obvious that human beings are capable of both creating, and solving all kinds of environmental problems.

But this outbreak of epidemics like COVID-19 reveals humans are nowhere near as special as we like to think. The emergence of COVID-19 has challenged the human-centered relationship between humans and nature. From the prehistoric hunting-gathering society to diverse modern society, in this evolution, somewhere human beings reduced all other species to unemotional machines. Now, it is the time when we must try to understand and appreciate the limitations of the human being as a part of the ecosystem.

In 1973, a Norwegian philosopher Arne Naess introduced us with the term “deep ecology” which claims that all living creatures have same right to live and flourish and human being is just as important as an insect in this ecosystem. As part of the ecosystem, humans must learn to live within nature, according to nature’s laws, and learn to accept our role as one among many. 

Deep ecology and our life today

Deep ecology is an emerging philosophical concept of ecology, which focuses on our moral obligation to protect the environment. It is the radical idea that all life has the right to exist, that no one species is more important than another. This is an ecocentrism philosophy and entirely rejects anthropocentrism. Deep ecology has eight principles. Below we list the concepts and some important details to understand how they are relevant to our life in quarantine.

  • Human and nonhuman life on Earth has a value independent of its usefulness to humans: This world is a wonderful place, and humans often are awed by the wonders of the animals. But there is an underlying aspect, we as humans, vehemently disregard that we are just another species of animals. Humans decide for everything in this world, where it should have been a symbiotic correspondence as every being on earth is entitled to live. Since the beginning of the quarantine period, we have seen that the dolphins have come back in the canals of Italy, endangered sea turtles have laid eggs on beaches in Brazil and India. Human activity destroyed their habitats as they are not useful to humans. The COVID-19 makes us understand that these ‘useless’ nonhuman creatures have similar importance to maintain ecological balance.
  • Biodiversity contributes to this value: From an individual standpoint, deep ecology may seem a bit pessimistic, but most of the discourse regarding this particular philosophy is undeniable. Imagine a world with increasingly low biodiversity, will that be an example of sustainable ecology? This kind of power exhibition of the human population has resulted in a decrease in biodiversity. Land use and land cover changes are responsible for habitat loss, degradation, and fragmentation which in turn affect biodiversity in any region. Besides, the introduction of exotic species and genetically modified organisms, pollution, and overexploitation of resources are some major human-induced threats to biodiversity. The COVID-19 has reduced the activity of the human population and helped to recover the biodiversity on the earth.
  • Humans have no right to reduce this biodiversity except to satisfy vital human needs: The basic idea of deep ecology is about considering human as just another species, how the pride of intelligence has brought up a war which is likely never to end. However, the so-called practicality of humans to be a doctrine of everything on earth is vehemently reducing biodiversity. There is no doubt the humans have destroyed the weather pattern as well as the biodiversity to such an extent that it has become irreversible. Quite a varied species had become extinct due to poaching, also with the name of sustainable hunting humans ethically hunt animals.
  • A substantial percentage of the human populationmust be eliminated: The deep ecologist thinks that a substantial percentage of the human population must be eliminated to establish the balance of the environment. However, it is unethical to kill humans; as a result, they have become the highest populated species that adversely affect the ecology. There are some alternative ways to check the human population. These are war, epidemics like COVID-19, famines and other natural calamities that have eliminated millions of life till date.
  • Humans interfere with the world too much already, and this activity is worsening: From the early age of civilization, humans had the impulse to create things to lower the proximity of labour. The striking of stones gave them fire to burn and round shaped stones formed the first transport. Since then humans have never stopped for a moment to make things easy for their own cause. It was pretty much confined to the discoveries until humans vehemently started to interfere with the world so much that they turned themselves into a paradox. During this time of COVID-19 pandemic, the violence of human interference is becoming more prominent. Be the virus dispersed from the wet market of Wuhan, or from some institute of virology, both are the result of too much power exhibition upon other species. The constant need for change in the lifestyle to make it easier is nothing but a better way to sugar-coat the brutality in the name of development. For the record, there is one only thing humans are good at, and that is interfering. And by doing that they confirm how wonderful that world would have been without them.
  • A new political and economic model must be devised to replace that of present governments: The human race does need a government completely designed in a new pattern. Humans often talk about the urgent need to protect the plant, but then it is wrong. The plant doesn’t need our protection; the world has sustained without humans; humans need to defend their home. Environment-friendly governance is highly required to bring back the ecological balance. Sound environmental policies have to be formed to reduce the human impact on the environment. Besides, new economic models have to be developed to secure human livelihoods.
  • Individuals must be content with the situation they are in instead of striving for a higher standard of living: The concept of self-awareness has projected in such a manner that man has become selfish. The very attitude of overconsumption has increased the global race. Thus, humans became very derogatory to their norms. This excessive consumption of wealth is drying the resources gradually which in turn destroys the balance of the ecosystem. 
  • Deep ecologists have an obligation to implement the above: Deep ecologists always want to establish the right of nonhuman life to preserve the biodiversity of any region. Deep ecologists organize workshops to grow ecological awareness among the human population, to make them environment friendly and to heal our relationship with the earth

Time to rethink…

It is high time we understood that all other ecosystem beings are not meant for human ends. It is ethically wrong and the source of environmental crises. Human needs are unlimited but the planet has limited capacity to meet them. In both the short and long term, the benefits of anthropocentric pressure to satisfy human needs are much lower than the potential costs to society. Ultimately, lost ecological infrastructure and the decline of natural capital, including human health, causes a decline in inclusive wealth. Before the impact becomes more negative we should rethink the relationship between humans and nature keeping deep ecology in the backdrop.

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