Punjab dominates stubble burning but UP’s share rises, Delhi’s AQI enters danger zone in September

AQI worsens in Delhi, stubble burning shifts

Punjab, known to be India's rice bowl for its significant cultivation, has once again emerged as the epicentre of stubble burning this season, accounting for nearly 62 percent of crop residue fires between September 15 and 29, provisional government data has shown.

However, Uttar Pradesh, is beginning to play a much bigger role with its share climbing to 27 percent in 2025, compared with just 3 percent in 2020.

The shift has been noted as the National Capital Territory's air quality has started showing worrying signs of deterioration. September 2025 turned out to be the first month since 2016 when the average Air Quality Index (AQI) stayed above 100 throughout, signalling persistent pollution even before the onset of the winter season's smog. Studies last year had estimated that stubble burning contributed as much as 31 percent to the worsening of AQI levels in the capital region.

Shifting State-level Dynamics

Between 2018 and 2022, Punjab had consistently contributed more than 70 percent of India’s stubble burning incidents, though its share slipped to 29 percent in 2024 as fires surged in Madhya Pradesh, which then accounted for 44 percent of cases.

Uttar Pradesh’s share stubble burning has since doubled, rising to 41 fires so far this season compared with Punjab’s 96. Haryana, by contrast, has seen a sharp drop from 60 fires last year to just seven for this time of the year. In the second half of September 2023, Punjab had accounted for 62 percent of incidents and Haryana 23 percent, while in 2025, Punjab’s dominance has returned but UP has stepped into Haryana’s place.

Why it Matters

The persistence of AQI above 100 in September — a threshold indicating unhealthy air quality — shows Delhi’s pollution challenge extends beyond stubble burning alone. Vehicle emissions, dust and local biomass burning add to the mix, but farm fires are expected to accelerate the deterioration in coming weeks as harvesting peaks in northern states.

For Delhi, the next two months will likely be decisive in determining whether this year’s smog season breaks past records of severity.