Delhi's average air quality index (AQI) stood at 369 in the ‘very poor’ category on Saturday as a thick layer of smog enveloped the national capital on the eve of Diwali, reducing visibility. The air quality is expected to deteriorate to the ‘severe’ category on Sunday, with festival-related celebrations, vehicular emissions and the peak stubble-burning season likely to add to the pollution load, PTI reported.
Of the 59 monitoring stations that recorded data on Saturday, 16 reported ‘severe’ air quality, while 29 remained in the ‘very poor’ category. The highest AQI of 452 was recorded near IIT Delhi.
The city's average AQI registered a marginal improvement from 382 on Friday to 369 on Saturday, but remained close to the threshold of 401 for the ‘severe’ category. Several monitoring stations had already recorded AQI levels above 400.
According to the Air Quality Early Warning System (EWS) for Delhi, air quality is likely to remain in the ‘severe’ category on November 8 and 9. The outlook for the following six days indicates that pollution levels are expected to fluctuate between the ‘severe’ and ‘very poor’ categories.
The Central Pollution Control Board (CPCB) classifies AQI readings between 0 and 50 as ‘good’, 51 and 100 as ‘satisfactory’, 101 and 200 as ‘moderate’, 201 and 300 as ‘poor’, 301 and 400 as ‘very poor’, and 401 and 500 as ‘severe’.
Weather and air quality experts have attributed the anticipated deterioration to unfavourable meteorological conditions, Diwali-related celebrations, vehicular emissions and the peak period of stubble burning in neighbouring states.
Low wind speeds and poor ventilation are also hindering the dispersion of pollutants. According to the EWS, a ventilation index below 6,000 square metres per second, along with an average wind speed of less than 10 kmph, is unfavourable for the effective dispersal of pollutants.
PM10 was the predominant pollutant in Delhi on Saturday.
The transport sector was the largest contributor to the city's pollution, accounting for 21.4 per cent of the total, according to the Decision Support System (DSS) for Delhi. Stubble burning contributed 1.7 per cent, with its share forecast to rise to 5.4 per cent on Sunday, PTI reported.
Satellite data showed that 589 incidents of crop residue burning were detected across six states on Friday. Punjab accounted for 357 incidents, followed by Madhya Pradesh with 139, Rajasthan with 58, Uttar Pradesh with 23, Haryana with nine and Uttarakhand with three.
A total of 6,226 farm fire incidents were detected across the six states between September 15 and November 6.
The figures were provided by the Consortium for Research on Agroecosystem Monitoring and Modelling from Space (CREAMS) Laboratory of the Indian Agricultural Research Institute in its bulletin, PTI reported.
(With PTI inputs)
