The only good thing that has happened in this pandemic is air pollution getting curtailed to long lengths. A team of 10 interdisciplinary investigators from the University of Surrey's renowned Global Centre for Clean Air Research (GCARE), including Ph.D. students and post-doctoral researchers, have united to develop a rapid assessment of the impact COVID-19 has had on air quality.
Figures from the World Health Organization show the ongoing pandemic has caused more than 477,000 deaths worldwide as of June 2020, 14,000 of which occurred in India. In this recent study, published by Sustainable Cities and Society, researchers from Surrey's GCARE studied the levels of damaging fine particulate matter (PM2.5) originating from vehicles and other non-vehicular sources in five Indian cities—Chennai, Delhi, Hyderabad, Kolkata, and Mumbai—from the start of the lockdown period until 11 May 2020. The team analyzed PM2.5 distribution and contextualized their findings against those from other cities from across the world. The team also reconnoitered potential factors influencing differences between divergent concentration changes in different cities, as well as aerosol loadings at regional scale.
The results showed that the lockdown reduced concentrations of harmful particles across all five cities, from a 10% reduction in Mumbai up to a 54% reduction in Delhi. These reductions in PM2.5 were found to be comparable to reductions in other cities across the world, such as in Vienna (60%) and Shanghai (42%).
While the reduction in PM2.5 pollution may not be surprising, the size of the reduction should make us all take notice of the impact we have been having on the planet.