COVID-19 Flattens Peak-hour Pollution

• 09 Apr 2020

An analysis carried out by the Centre for Science and Environment has assessed  hourly trend in PM2.5 and NO2 levels during the day before and after the lockdown and also on the day of the Janata curfew.

Key Features

• As vehicles go off the road after the country-wide lockdown in the wake of the novel coronavirus disease (COVID-19) outbreak, the typical two humps of daily pollution coinciding with morning and evening traffic peak-hours have nearly flattened out in India’s big cities.
• As cities slow down to fight the pandemic, daily average levels of particulate matter of size less than 2.5 micron (PM2.5) and nitrogen dioxide (NO2) have reduced sharply from the pre-lockdown days by close to more than half in Delhi and the towns of the national capital region (NCR).
• A similar trend is evident in other big cities including Mumbai, Kolkata, Bengaluru, Hyderabad and Chennai. But the impact of this overall declining trend is dramatic on daily peak-hour pollution.
• This brings out the pronounced effect of traffic on hourly pollution trends. With traffic minimised, hourly trends have plummeted, reducing daily exposures to toxic vehicular pollution.