Delhi Air Quality Worst Since 2021 After Diwali

In the days after Diwali, Delhi’s air quality plunged, with CPCB and independent analyses reporting AQI in the very poor to severe/hazardous range and 24‑hour PM2.5 spiking to about 488 µg/m3 — the worst levels since 2021 and at times ranking Delhi among the world’s most polluted cities. The surge was driven largely by local emissions from widespread firecracker use — including violations of permitted time windows and concerns over the effectiveness of ‘green’ crackers — and was compounded by stagnant winds and a temperature inversion that trapped pollutants, prompting activation of Stage II of the Graded Response Action Plan. Satellite and institute data indicated stubble‑burning made a generally low contribution to Delhi’s PM2.5 this season, though Punjab saw a temporary rise in fire counts and officials exchanged blame over cross‑border smoke. Authorities tightened restrictions and carried out seizures and arrests for illegal crackers (and liquor in some cities), but enforcement gaps and public non‑compliance were widely reported. Doctors and environmentalists warned of immediate respiratory and cardiovascular risks, urged masks and reduced outdoor exposure for children, the elderly and people with health conditions, and cautioned that pollution could worsen as winter conditions set in.