New Delhi: The contribution of stubble burning to Delhi’s PM2.5 levels Tuesday touched 4.1%, the highest this season. It had been negligible so far at less than 1%, but the share of farm fires in the city’s air quality is likely to rise sharply over the next three days.Decision Support System (DSS), which functions under Union ministry of earth sciences, has estimated this figure could be around 8% Wednesday, 13.3% Thursday and 10.4% Friday. The actual contribution of the burning of paddy residue to the city’s air quality will depend on the intensity of such fires and wind direction and speed.“The wind direction is likely to change to north-westerly, which may carry smoke to Delhi,” said Gufran Beig, founder of System of Air Quality and Weather Forecasting and Research (SAFAR) and chair professor at National Institute of Advanced Studies.The harvesting pattern is different this time compared to previous years, he said. “Last year, Punjab and parts of Haryana had floods, but this time, monsoon was weak. As a result, harvesting was delayed, with farm fires set to peak later than usual. Besides, as many farmers burn paddy residue after satellite overpass time, the burning pattern will be different,” Beig said.TOI had reported that this stubble burning season could be complex as the El Niño effect is expected to lead to fewer western disturbances, which bring rain to Delhi, and slower wind speeds, resulting in more smoke from stubble burning blowing into the city. The peak farm fire period is also expected to coincide with Diwali (Nov 8) this year, when winter conditions begin setting in.From Sept 15 to Oct 19 this year, Punjab recorded 368 farm fires, up from 308 during this period last year. Haryana reported just nine stubble burning counts, down from 38 last year.The contribution of stubble burning to Delhi’s PM2.5 was less in 2025 as the share of farm fires in Delhi’s air quality surpassed 10% on just seven days and was over 20% on only one day. It remained below 5% on most days. The figure was above 20% on 14 days in 2024, according to DSS.Punjab reported 5,114 farm fires last year, down from 10,909 in 2024, while Haryana recorded 662 incidents compared with 1,406 in 2024. Events of paddy residue burning in UP rose from 6,142 in 2024 to 7,290 in 2025. Rajasthan witnessed 2,890 cases last year as against 2,772 in 2024, and Delhi saw a reduction from 13 in 2024 to five last year.
