Kolkata: Cyclonic circulation brings year’s ‘best-ever air’
The city on Wednesday experienced the best-ever air quality of this year courtesy of the cyclonic circulation. In fact, the PM2.5 count fell below the stringent WHO-defined safe limit of 15µg/m³ for a 24-hour average. On Wednesday, the daily average of PM2.5 was 11.1µg/m³.