Delhi braces for 'severe' air pollution after Diwali as AQI climbs to 376

Delhi entered Diwali under a blanket of smog on Sunday, with air quality already ‘very poor’ and forecast to turn ‘severe’ after the evening’s celebrations.Weak winds were expected to trap pollutants, adding to concerns over firecracker smoke, vehicle emissions and stubble burning.The city’s average Air Quality Index (AQI) rose to 376 from 369 on Saturday. Jahangirpuri recorded the worst reading at 463.The Air Quality Early Warning System for Delhi forecast ‘severe’ conditions from November 9 for the next few days. SEVERAL AREAS ALREADY IN ‘SEVERE’ CATEGORYTwelve monitoring stations reported ‘severe’ air quality on Sunday, while 22 recorded ‘very poor’ levels. Smog reduced visibility across the capital.The Central Pollution Control Board classifies an AQI of 301–400 as ‘very poor’ and 401–500 as ‘severe’. Delhi’s citywide average remained below the severe threshold, though several neighbourhoods had already crossed it. PM2.5 was the main pollutant, with firecracker emissions adding to particulate matter levels.WEAK WINDS TO TRAP POLLUTIONWeather conditions offered little scope for improvement. The early warning system said ventilation was unfavourable for the dispersal of pollutants.A ventilation index below 6,000 square metres per second, combined with average wind speeds below 10 kmph, is considered unfavourable for dispersal. Such conditions allow pollutants to accumulate near the surface.The Decision Support System for Delhi projected that transport would account for 19 per cent of the city’s pollution on Sunday, making it the largest contributor among the sources assessed.Stubble burning was expected to contribute 3.5 per cent, with its share forecast at about 2.99 per cent on Monday.- Ends