Air quality in Delhi-NCR turns 'severe' post Diwali

A day after the Diwali celebrations, air quality in Delhi and surrounding areas on Sunday dipped to 'severe' due to firecracker emissions at various places. 

The air quality in Delhi-NCR plunged into the 'severe' category with Air Quality Index (AQI) reaching 421 on Sunday morning, according to the latest estimates updated by System of Air Quality and Weather Forecasting And Research (SAFAR). 

Most of the areas in the national capital including Delhi University, Pusa Road, Lodhi Road, Mathura Road, IIT-Delhi, Indira Gandhi International Airport (Terminal-3) and Ayanagar recorded air quality in the 'severe' category with an AQI of 479, 433, 392, 427, 398, 468 and 424 respectively.

Earlier a layer of haze was seen over Delhi-NCR on Diwali night as people defied ban and bursted firecrackers with calm winds allowing accumulation of pollutants. 

The city recorded an overall Air Quality Index or AQI of 414 on Saturday, which falls in the 'severe' category. The 24-hour average AQI was 339 on Friday and 314 on Thursday.

Stubble burning accounted for 32 per cent of the city's PM2.5 pollution, which is about 3 per cent the diameter of a human hair and can lead to premature deaths from heart and lung diseases.

It was 331 microgram per cubic metre (µg/m3) in Delhi-NCR at 10 pm, above the emergency threshold of 300 µg/m3. The safe limit is 60 µg/m3.

Almost all areas in the city logged PM2.5 levels above 400 with many regions nearing the 500-mark. Anything above 60 is considered unhealthy. A thick layer of smog enveloped the entire region reducing the visibility.

Residents complained about stinging eyes, sore throat and breathlessness as the city grappled with the third wave of the coronavirus pandemic.

Calm winds have exacerbated the situation, allowing the accumulation of pollutants, weather officials said.

The Ministry of Earth Sciences' air quality monitor, SAFAR, said, 'Even a small increase in local additional emissions is likely to have significant deterioration impact on Sunday and Monday.'

It said, peak levels of PM10 and PM2.5 are expected between 1 am and 6 am in case of additional internal emissions.

Delhi recorded a 24-hour average AQI of 337 on Diwali last year (October 27), and 368 and 400 in the next two days leading to pollution levels remaining in the 'severe' category for three days.

This time, the India Meteorological Department has said that a fresh western disturbance could increase the wind speed and improve the air quality in Delhi-NCR after Diwali.

Light rain is likely on Sunday under the influence of a western disturbance. It is still unclear if it is enough to wash away pollutants, Kuldeep Srivastava, the head of the IMD's regional forecasting centre, said.

VK Soni, the head of the IMD’s environment research centre, said the wind speed is expected to pick up thereafter and the wind direction will be east-southeasterly.

There will be a significant improvement in air quality by November 16, Mr. Soni said.

The Delhi Police arrested 10 people for selling firecrackers and registered 12 cases in the national capital, officials said on Saturday.

The Delhi government and the National Green Tribunal (NGT) has totally banned on the sale or use of all kinds of firecrackers in the National Capital Region (NCR) from November 9 midnight to November 30 midnight, noting the horrific pollution levels.

A bench led by NGT Chairperson Justice Adarsh Kumar Goel clarified that the direction will apply to all cities and towns in the country where the average of ambient air quality during November 2019 was in "poor" and above categories.