New Delhi: Ahead of the World Environment Day on June 5, experts have outlined several environmental factors that saw improvements in India as a result of the lockdowns, namely air quality, noise pollution, water quality, and biodiversity among others
The lockdowns enforced due to the COVID-19 pandemic led to large improvement in air quality in India, say scientists who suggest that such interventions may be used as a possible emergency measure to combat severe air pollution episodes like those witnessed in Delhi-NCR region during the winter months.
Ahead of the World Environment Day on June 5, experts have outlined several environmental factors that saw improvements in India as a result of the lockdowns, namely air quality, noise pollution, water quality, and biodiversity among others due to reduced industrial and human activities.
On March 24, the Union government ordered a nationwide lockdown for 21 days, limiting the movement of people in India as a preventive measure against the COVID-19 pandemic.
Since then the lockdown has been extended many times with gradual lifting of restrictions.
“There is a large improvement in air quality, especially in urban areas — from alarming or poor to satisfactory or good. The main reason is reduced human activities,” said S K Satheesh, Professor at Centre for Atmospheric & Oceanic Sciences, Indian Institute of Science (IISc) Bangalore.
“On an average, reduction in particulate matter (PM) concentrations over southern part of India is around 50-60%, and over the Indo-Gangetic basin, including Delhi, UP, Bihar, West Bengal etc it is as much as 75%,” he said.
Satheesh noted that the major contributing factors of pollution are transport vehicles, industries, crop-residue burning, waste burning and so on.
He explained that in cities, more than half of the air pollution is caused due to vehicular emissions, adding that during the lockdown, there was a large reduction in the number of vehicles on road.
According to two studies, published in the journal Geophysical Research Letters in May, the levels of two major air pollutants, including nitrogen dioxide, drastically reduced since lockdowns were enforced worldwide in response to the COVID-19 pandemic.
In India, satellite data has shown a significant drop in particulate matter or aerosol levels after the COVID-19 lockdown over most parts of the country, Satheesh said.
“Our field measurements show that there is a substantial reduction in the concentration of suspended particulate matter (PM), a major component of air pollution, in the atmosphere due to reduced human activities as a consequence of the lockdown,” he said.
The scientist explained that multi-spectral measurements of aerosol absorption, in addition to data available from Central Pollution Control Board (CPCB), indicate that the drastic decrease in pollution levels is mainly due to a reduction in fossil fuel burning emissions.