Delhi’s air quality remained in the ‘very poor’ category for the fourth consecutive day on Thursday, with the city’s 24-hour average Air Quality Index (AQI) recorded at 369 and forecasts warning that pollution could worsen into the ‘severe’ category between Friday and Sunday, ahead of Diwali.
The Central Pollution Control Board recorded the city’s AQI at 4 pm on Thursday. Although the reading was lower than Wednesday’s 377, it remained close to the severe threshold. The city’s average AQI was 350 on Tuesday and 324 on Monday, indicating that pollution levels have stayed elevated through the week.
The CPCB classifies AQI readings from 301 to 400 as ‘very poor’ and readings from 401 to 500 as ‘severe’. Of the active air-quality monitoring stations in Delhi, 18 recorded readings in the severe category on Thursday. Jahangirpuri reported the highest reading, with an AQI of 454 at 4 pm.
The Air Quality Early Warning System forecast that Delhi’s air would remain in the very poor category on Thursday and could deteriorate further from Friday to Sunday. Its bulletin, which provides a six-day forecast, said air quality could remain between the severe and very poor categories during the period.
The forecast places added significance on the days leading up to Diwali, when fireworks and changing weather conditions can affect pollution levels. However, the supplied assessment identifies several contributors to Delhi’s air pollution, including transport emissions and crop-residue burning.
The Decision Support System for air-quality management, operated under the Ministry of Earth Sciences, estimated that crop-residue burning accounted for 15.601 per cent of Delhi’s pollution contribution on Thursday. Its estimate for Friday was higher at 19.201 per cent, before falling sharply to 1.575 per cent on Saturday.
The system’s estimates also showed that the relative contribution of pollution sources can change from day to day. On Wednesday, vehicle emissions were assessed to have contributed 15.5 per cent of Delhi’s pollution, while crop-residue burning accounted for 20.2 per cent.
The figures underline the role of transport emissions in Delhi’s pollution profile even as the seasonal debate over stubble burning intensifies before Diwali. They also show why city-level air-quality management depends on readings from monitoring stations, source-apportionment models and short-term forecasts rather than on a single pollution source.
The immediate public-health concern is the concentration of pollution in the very poor and severe categories across parts of the city. The next operational milestone is the Air Quality Early Warning System’s forecast period from Friday to Sunday, when Delhi’s air is expected to face a heightened risk of reaching the severe category.
