India / Delhi's air quality turns 'severe', worst AQI on Diwali in 4 years

New Delhi: The air quality in the national capital deteriorated to the “severe” category a day after Diwali on Sunday, with the Air Quality Index (AQI) at ITO area and Anand Vihar recorded as 461 and 478 respectively, according to Delhi Pollution Control Committee (DPCC) data.

A thick blanket of smog enveloped several areas across Delhi in the morning, reducing visibility. An improvement in the air quality is expected starting the second half of Sunday, with light rain expected across the capital. Wind direction is expected to change to south easterly, reducing the impact of farm fires on Delhi’s air.

The AQI for PM 2.5 pollutant stood at 460 in Pusa, 475 in Patparganj, 450 in Lodhi Road, 491 in Ashok Vihar, 500 in Jahangirpuri and 442 in the IGI airport area. An AQI between 101 and 200 is considered moderate, 201-300 ‘poor’, 301- 400 ‘very poor’ and 401-500 ‘severe’, while the AQI above 500 falls in the severe plus category.

With many Delhiites ignoring the cracker ban in the city, on Saturday night, the AQI was recorded as 414 — the worst AQI in the city since 2016 on Diwali. On Friday, it dipped to 339 — in the ‘very poor’ category.

The city recorded a 24-hour average AQI of 337 on Diwali last year (October 27), and 368 and 400 in the next two days. Thereafter, pollution levels remained in the “severe” category for three days in a row.

The share of stubble burning in PM 2.5 also increased from 14 per cent on Friday to 32 per cent on Saturday owing to transport-level North-Westerly winds with adequate speed, SAFAR said.

“Isolated to scattered rainfall under the influence of fresh Western Disturbance by November 15 is also expected. These factors will greatly help in flushing out the impact of any additional locally generated emissions and biomass related impact to make AQI in the lower end of very poor by November 16,” SAFAR’s official forecast said.

The Central Pollution Control Board has asked all State Pollution Control Board (SPCBs), Pollution Control Committees and Regional Directorates of CPCB to conduct ambient air quality monitoring at two or three locations for seven days after Diwali to study the impact of pollutants.