Delhi’s air quality edged closer to the ‘severe’ category on Friday, with the average Air Quality Index (AQI) settling at 400 in the ‘very poor’ category amid rising pollution and a layer of smog that reduced visibility. Air quality in the national capital is predicted to turn ‘severe’ from Saturday, with Diwali celebrations, vehicular emissions and the peak stubble-burning season expected to add to the pollution burden. Unfavourable meteorological conditions are further aggravating the situation.
Of the 58 air quality monitoring stations that recorded data on Friday, 26 recorded AQI in the ‘severe’ category, 31 in the ‘very poor’ category and only one, Lodhi Road, recorded ‘poor’ air quality. The city’s average AQI deteriorated from 369 on Thursday to 382 on Friday, bringing it closer to the ‘severe’ threshold of 401. Several air quality monitoring stations have already breached this mark, indicating a further deterioration in air quality across the capital.
Several monitoring stations in the national capital recorded ‘severe’ air quality levels. IIT Delhi and Rohini topped the list with an AQI of 474 each, followed by Punjabi Bagh at 465, RK Puram at 443, ITO at 422, Firoz Shah Road at 420 and India Gate at 403.
With Diwali approaching, social media users have also been flagging the deteriorating air quality, with several saying they could already “smell Diwali in the air”.
According to the Air Quality Early Warning System for Delhi, the air quality is likely to remain in the ‘severe’ category from November 7 to 9. The outlook for the subsequent six days indicates that the air quality is likely to fluctuate between the ‘severe’ and ‘very poor’ categories. As pollution worsened, the CAQM on Friday imposed GRAP stage three measures in Delhi-NCR.
Under GRAP-3, strict restrictions are placed on dust-generating and air-pollution-causing construction and demolition activities in NCR.
Weather and air quality experts have attributed the anticipated deterioration in air quality to unfavourable meteorological conditions, the onset of Diwali-related celebrations, vehicular emissions and the ongoing peak period of stubble burning in neighbouring states.
According to the Early Warning System, a ventilation index below 6,000 square metres per second, coupled with an average wind speed of less than 10 kilometres per hour, is unfavourable for effective pollutant dispersion.
PM2.5 was the predominant pollutant in the national capital on Friday. Fine particulate matter, which can penetrate deep into the respiratory system, remains a major concern amid the deteriorating air quality.
According to the Decision Support System for Delhi, the transport sector was the city’s largest polluter on Friday, accounting for 17.9 per cent, followed by stubble burning at 13 per cent.
Among Delhi’s local emission sources, energy production contributed 1.4 per cent, peripheral industries 3.6 per cent, waste burning 1.7 per cent, construction 2.7 per cent, road dust 1.3 per cent, residential sources 4.4 per cent and other sectors 1.2 per cent.