New Delhi: The capital’s air quality remained severe on Sunday, a day after Commission for Air Quality Management invoked Stage-IV measures under Graded Response Action Plan (GRAP). The 4pm air quality index, considered the day’s standard reading, stood at 440, a shade higher than 428 at 8pm on Saturday — both in the severe range. This was the highest Jan reading since the index had touched 447 on Jan 14, 2024, and the joint-worst on record for the second half of the month — 440 was also the reading on Jan 17, 2019 — according to Central Pollution Control Board data.
All previous peak readings in Jan, including the all-time high of 460 recorded on Jan 15, 2021, were from the first half of the month. The city did not record a single severe air day in Jan last year. Sunday also marked Delhi’s first severe air quality day of the year and the first since Dec 29, 2025, when the reading was 401. It was also the second-worst this winter, after a peak of 461 on Dec 14. Calm winds linked to a western disturbance, along with dense fog, led to the air quality plunging. The highest contribution of Delhi’s air pollutants was from its own transport sector (12.5%), followed by emissions from Gautam Budh Nagar at 12%, Ghaziabad (9.4%) and Bulandshahr at 8.34%, according to the Centre’s Decision Support System, which estimates the contribution of sources impacting the capital’s air quality. The air is likely to improve to ‘very poor’ on Monday and remain within the range on Tuesday, according to the Centre’s Air Quality Early Warning System.While meteorological conditions played a key role, emissions from both local and neighbouring districts remained high, experts said. Sunil Dahiya, founder and lead analyst at think tank Envirocatalysts, said low wind speed, stable atmospheric conditions, stagnation of local emissions and a higher contribution from neighbouring districts on the city’s east and south-west resulted in a spike in pollutants. “An urgent intervention for reduction of emission load at major sources, along with other GRAP measures in Delhi-NCR, may help reduce the severity of the episode. However, long-term relief will follow reduction of systematic emission load at the sources across a larger airshed,” he said. Anumita Roychowdhury, executive director (research and advocacy) of Centre for Science and Environment, said, “This is the time of the year when adverse atmospheric conditions intensify and trap the already high levels of pollutants in the region. This has also been a long dry spell. The only way to mitigate this air emergency is to reduce round-the-year pollution.”Dense fog shrouded Delhi, with visibility dipping to zero in many places. At Safdarjung, the city’s base station, it remained low between 2.30 am and 8.30 am. At Palam, visibility dropped to 100 metres at 7.30 am, according to India Meteorological Department (IMD). The department issued a yellow alert for moderate to dense fog during the morning hours of Monday. While no flights had to be cancelled or diverted at Indira Gandhi International Airport, several departures and arrivals were delayed. Data from flight-tracking website FlightRadar24 showed that over 500 flights were delayed, with an average delay of about 34 minutes, at the airport. The minimum temperature was 5.3 degrees Celsius on Sunday, two notches below normal, and 0.9°C higher than Saturday’s minimum. As cold wave conditions eased across the region, the minimum is predicted to rise to around 9°C to 11°C by Jan 23. The maximum temperature was recorded at 22.7°C, three notches above normal. It is likely to stay between 24°C and 26°C on Monday. The city may receive very light rain on Jan 23 under the influence of a fresh western disturbance, said a Met official.
