As the air quality in the national capital has started to worsen over the past few days and stubble burning in Punjab and Haryana is being blamed as one of the reasons behind it, experts and officials in Punjab have dismissed it as a key factor.
As per the Punjab Pollution Control Board (PPCB), the average air quality index (AQI) in Punjab has been 120 from September 21 till October 14, 2020, while the AQI in Delhi has been 179 for the same period. The stubble burning cases in Punjab started around September 21.
PPCB member secretary Kurnesh Garg said that AQI levels in Punjab during this period had largely remained within ‘moderate’ level whereas in Delhi the AQI has slipped into ‘very poor’ category.
“Contribution of stubble burning from Punjab is minimal to Delhi’s air pollution. The ambient air quality of Delhi remains poor or very poor even in December, January and February even though there’s no stubble burning during that period. The major factor of air pollution in Delhi is inherent to the anthropogenic, vehicular, solid waste burning and industrial activity within the NCR. Even active farms fires in the NCR are significantly responsible for deteriorating the Delhi environment than Punjab,” he said.
As paddy (rice) harvesting has gathered momentum in Punjab, as many as 3,517 cases of stubble fire incidents have been reported between September 21 and October 14.
A joint study by the Indian Institute of Science Education and Research (IISER), Mohali, and PPCB in 2018 — “Impact of Aerosol from Paddy Residue Burning on New Delhi-NCR” —had concluded that a significant fraction of Delhi’s air pollution problems are located within the NCR or in Uttar Pradesh. And it is the dominant reason for the poor air quality persisting throughout the winter instead of improving in December onwards as it does in Punjab relative to the paddy burning season.
The hypothesis of stubble fires being responsible for most of the PM enhancements in Delhi does not hold, the study points out.