Delhi air: After improving to the ‘poor’ category, the air quality in Delhi went down to be ‘very poor’ on Friday morning. The overall Air Quality Index (AQI) of the city stood at 329. A few areas like Rohini registered an AQI of 357, highest since January 2021
“The winds had been mostly calm, so pollutants have accumulated in the atmosphere. The current pollution is mostly from local emissions, but fire counts in neighbouring Punjab and Haryana are increasing significantly. Over the last two days, there have been more than 1200 fire counts,”said VK Soni, senior weather scientist, India Meteorological Department.
According to data from the monitoring stations listed on the government website showing the National Air Quality Index, AQI in Anand Vihar stood at 834, the highest in the city. A few more areas like Rohini registered an AQI of 357, the Jhilmil area recorded an AQI of 418 and the AQI in Sonia Vihar stood at 332.
Meanwhile, Noida, which is part of the national capital region, recorded an AQI of 351 while Gurugram’s AQI stood at 324, as per data released by SAFAR-India.
An AQI between zero and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very poor”, and 401 and 500 “severe”.
The government’s monitoring agency System of Air Quality and Weather Forecasting and Research (SAFAR) said fine particles contributed ~ 52% to PM10. It added the share of stubble fires (1082) in the northwest region to Delhi’s PM2.5 was meagre.
SAFAR said winds at the transport level (750 – 1000 m) were weak and blowing mostly from the northwest direction. “Local surface winds are calm to 8 km/h…for next three days that cause weak dispersion of pollutants. Peak mixing layer height’ during daytime (~1.0 – 1.5 km) leads to moderate vertical dispersion of pollutants.”