ESA Map: Concentration of key air pollutant drops by around 40% in India in lockdown

NEW DELHI: Concentration of sulphur dioxide, a significant contributor to air pollution, dropped over India during the Covid-19 lockdown, says a report of the European Space Agency (ESA).
A new satellite map, released by the ESA on Wednesday, shows that the drop is more significant over Delhi and areas around many large coalfired power plants as well as other industrial zones in the country.
Attributing the drop to substantial reduction in human and industrial activities since the beginning of lockdown in March, the report says the concentration of sulphur dioxide in polluted areas in India had decreased by around 40% in April this year compared to April 2019.
It, however, notes that though some large plants in Odisha, Jharkhand, and Chhattisgarh have maintained a substantial level of activity, such operation appears to have ceased entirely in other parts of the country in April which coincides with the first two phases of lockdown in India.
The new maps are produced by scientists using data from the Copernicus Sentinel-5P satellite. The Copernicus Sentinels are a fleet of dedicated EU-owned satellites, designed to deliver a wealth of data and imagery that are central to the European Union’s Copernicus environmental programme.
“In India, emissions of sulphur dioxide have strongly increased over the last ten years, exacerbating haze problems over large parts of the country. However, owing to the Covid-19 pandemic, human and industrial activity dropped considerably since the beginning of its lockdown on 25 March 2020,” says the report.
Certain reports had last year flagged India as the world’s largest emitter of anthropogenic sulphur dioxide.
Though some atmospheric sulphur dioxide is produced from natural processes globally, such as volcanoes, a substantial amount is produced by human activities – predominantly from power plants burning fossil fuels - and therefore environmentalists and proponents of sustainable development across the globe have consistently been pitching for shift from current fossil fuel dependent economy to clean energy based systems.
The lockdown period had seen substantial decline in concentrations of other pollutants as well. An independent research organisation, Centre for Research on Energy and Clean Air (CERA), had recently noted decrease in level of nitrogen dioxide - another key pollutant - in first two weeks of the lockdown period compared to its levels during two weeks before the lockdown period.
The CERA in its analysis used both ground and satellite data, showing “drastic and clear reductions” in pollution levels, and attributed it to decreasing fossil fuel consumption in transportation, industries and energy sector.