Delhi winter AQI showed no sustained improvement from 2022 to 2026: CREA

Delhi’s mean winter AQI was 295 in 2025-26, higher than the 280 recorded in 2022-23, an analysis by the Centre for Research on Energy and Clean Air has found.

The figure rose to 304 in 2023-24, fell to 285 in 2024-25 and climbed again last winter. Median AQI followed a similarly uneven path, moving from 294 in 2022-23 to 305 in 2025-26.

Using daily AQI bulletins and Graded Response Action Plan records from October 2022 to February 2026, CREA found Delhi was under Stage II or stricter curbs on about 78% to 83% of observed days each winter. The city logged 32 days under the two toughest stages, III and IV, in 2022-23; that rose to 57 in 2024-25 before falling to 42 last winter.

CREA also examined 12 occasions when restrictions were escalated to Stage III or IV. In 10 cases, mean AQI in the following week was higher than in the preceding week. The group cautioned that this does not establish that GRAP measures caused pollution changes, since weather conditions and the measures themselves vary.

Its recommendation is to cut emissions at source across the wider NCR airshed, treating emergency restrictions as a last line of defence.