Delhi pollution: AQI nears severe mark at 369, several areas cross 400

New Delhi: Delhi’s Air Quality Index (AQI) stood at 369, in the ‘very poor’ category, on Saturday as smog enveloped the city on the eve of Diwali and reduced visibility.

Air quality is forecast to turn ‘severe’ on Sunday, with Diwali celebrations, vehicular emissions and the peak stubble-burning season expected to add to the pollution burden.

Of the 59 monitoring stations that recorded data on Saturday, air quality was in the ‘severe’ category at 16 stations and in the ‘very poor’ category at 29. The worst AQI reading of 452 was recorded near IIT Delhi.

The city’s average AQI improved slightly from 382 on Friday to 369 on Saturday, remaining close to the ‘severe’ threshold of 400. Several monitoring stations have already crossed this mark, indicating a deterioration in air quality across the national capital.

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 subsequent six days indicates that air quality is likely to fluctuate between the ‘severe’ and ‘very poor’ categories.

As per the Central Pollution Control Board (CPCB), an AQI between 0 and 50 is classified 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, the onset of Diwali-related celebrations, vehicular emissions and the peak period of stubble burning in neighbouring states.

Unfavourable meteorological conditions are further aggravating the situation. According to the EWS, 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 the effective dispersion of pollutants.

PM10 was the predominant pollutant in the national capital on Saturday.

According to the Decision Support System (DSS) for Delhi, the transport sector was the largest contributor to the city’s pollution on Saturday, accounting for 21.4 per cent. The contribution of stubble burning was estimated at 1.7 per cent, with forecasts suggesting that it could rise to 5.4 per cent on Sunday.

Satellite data showed that 589 residue-burning incidents were detected across six states on Friday. Of these, 357 were reported in Punjab, nine in Haryana, 23 in Uttar Pradesh, 58 in Rajasthan, three in Uttarakhand and 139 in Madhya Pradesh.

A total of 6,226 farm fire incidents were detected across the six states between September 15 and November 6.

The data was provided by the Consortium for Research on Agroecosystem Monitoring and Modelling from Space (CREAMS) Laboratory of the Indian Agricultural Research Institute in its bulletin.