Breathe easy: 40% drop in Sulphur Dioxide concentration in air across India

The observations are significant as India was in 2019 named the world's largest emitter of SO2.

Sulphur Dioxide (SO2) concentration, an air pollutant released by the burning of fossil fuels, reduced across India by almost 40 per cent when the country was shut down for more than two months to contain the coronavirus pandemic, data released by the European Space Agency (ESA) shows.

ESA’s observations show SO2 concentration in Delhi fell when coal-fired power plants and industries shut down for the lockdown, which started on March 24 and now has been eased off. While power plants across the country ceased entirely, some in the states of Odisha, Jharkhand, and Chhattisgarh maintained a substantial level of activity.

The observations are significant as India was in 2019 named the world’s largest emitter of SO2. India’s emissions have increased in the last 10 years, leading to haze and poor air quality in cities including national capital New Delhi.

Coal-based power plants and oil refineries are responsible for two-thirds of the anthropogenic SO2 emissions. “The country ranking shows India as the top emitter of SO2 in the world, contributing more than 15 per cent of the global anthropogenic SO2 emissions,” said Greenpeace in a 2019 report.

"We have experienced a reduction in Sulphur dioxide, however, this is temporary and it's not going to benefit in the long run. We should not forget that because of the drastic fall in consumption in the industrial and commercial categories, the power demand has also gone down during the lockdown. This reduction in SO2 could be achieved in the long run with cleaner energy sources," said Avinash Chanchal, Senior Climate and Energy Campaigner for Greenpeace India.