Mumbai: Mumbai recorded the cleanest air of the year so far on Monday with an Air Quality Index of 28, and a sky that was a bright cerulean blue as opposed to the dull haze that is becoming the norm. On the same day, in comparison, SAFAR, which is the System of Air Quality and Weather Forecasting and Research, recorded the AQI levels at Pune, Ahmedabad and Delhi respectively as 73 (satisfactory), 64 (satisfactory) and 174 (moderate). Mumbai’s AQI of 28 is indicative of good air quality as per the National Ambient Air Quality Standards (NAAQS).
Officials attributed the dip in pollution to favourable weather conditions, including the recent widespread rainfall in Mumbai and strong landward winds.
“Monday was among the cleanest ever air days for Mumbai since we began recording pollution levels in 2015. It was the cleanest day of the year so far. In late May, the city’s AQI had touched between 250-300 on a couple of days, which is in the ‘poor’ category, so the improvement over three weeks has been significant,” said Gufran Beig, project director at SAFAR. “If the wind speed slows down over the next day or so, the air quality will deteriorate again, but it’s common knowledge that during the monsoon season air quality is generally much better in Mumbai,” Beig added.
SAFAR has nine ambient air quality monitors in Mumbai. Mazagaon, Bandra-Kurla Complex and Worli recorded the cleanest air in the city with AQIs of 21, 23 and 26 respectively while Bhandup and Chembur recorded the highest AQIs, at 55 and 53 respectively on Monday.
An AQI of 100 to 199 is considered ‘moderate’, while 50 to 99 is considered ‘satisfactory’ and below 50 is considered ‘good’. AQI in excess of 200 is considered ‘poor’, above 300 ‘very poor’, above 400 ‘severe’ and above 500 is considered ‘severe+’. The lowest AQI ever recorded in Mumbai (since 2015) was 12, on September 4, 2019.