Stubble-burning declines, yet unchanged aerosol levels highlight gaps in data accuracy and environmental impact assessments.
Chandigarh: The debate over stubble-burning incidents in paddy sowing states has taken a fresh turn, with claims and counterclaims putting a question mark over the authenticity of the stubble-burning date being shared by the states, and the fire incidents detected by the National Aeronautics and Space Administration (NASA). The development has sparked a debate whether the farmers were outsmarting the satellites, or the state agencies were hiding the actual data of stubble- burning. Punjab and Haryana have claimed that nearly 30% decline in farm fires than the last year. Whereas the number of incidents of farm fires in other states like Madhya Pradesh and Uttar Pradesh continues to rise as Madhya Pradesh is topping the table with a whopping 13,385 incidents this year, against 11,736 incidents reported last year. Raising concerns over the authenticity of this data, during a hearing on November 18, the Supreme Court noted discrepancies and undercounting bias in the data collected by NASA’s polar-orbiting satellite and a Korean stationary satellite regarding farm fires. The court was informed that the polar-orbiting satellites capture fires only during their passage over Punjab and Haryana. To address the issue, the top court also directed the Centre and the Commission for Air Quality Management (CAQM) to include data from geostationary satellites alongside NASA’s polar-orbiting systems. Moreover, the Supreme Court on Friday once again directed the CAQM to submit the minutes of meetings attended by its members. This directive came after the court was informed that the issue of farmers reportedly evading geostationary satellites to conceal stubble-burning incidents had been a topic of discussion. Surge in air pollution every year, despite decreasing incidents of stubble-burning cases, also gives a boost to the doubts over the reliability of satellite data, as the states like Punjab and Haryana have reported a significant drop—over 30%—in stubble-burning incidents this year, and nearly 80 % fall than 2022. There were also reports that the farmers were misleading the satellites by burning the crop waste at night. However, experts have rejected such claims, stating that satellites are fully capable of capturing stubble-burning incidents even at night. Specialists from Punjab Agricultural University and the Punjab Pollution Control Board have clarified that satellite technology records such events round the clock. But ground reports suggest that some farmers have adopted some practices to mislead the authorities and burn stubble under the cover of darkness and plough the fields immediately, leaving no visible evidence of the act for the physical verification which is must for action against the farmers. During the visit for physical verification, officials found no incidents of farm fires.
“In lack of evidence, over 50% reported incidents detected by satellite were found inaccurate or not related to agriculture during the physical verification. The physical verification of all 1,000 incidents detected by the HARSAC in Haryana, revealed that only 500 of the incidents were related to agriculture”, said an official in Haryana State Agriculture Department, pleading anonymity.
“Also, some farmers adopted another technique as they collect the crop waste of several acres and burn it at one spot, this confuses the satellite and officials both, as the satellite counts it as a single incident. This also makes it easy for farmers to mitigate the crop waste”, said the official.
Professor Adarshpal Vig, Chairman of the Punjab Pollution Control Board, also dismissed these allegations, asserting, “The data collected by Punjab Remote Sensing Centre using ISRO and NASA satellites captures all events, day and night. This is a foolproof mechanism and the claims that the farmers are outsmarting satellites is purely fictional, and we are relying on this technology for the past several years.”
Sharing the data, Vig claimed that the state government’s efforts have successfully curbed farm fires, with stubble-burning incidents in Punjab dropping from 35,606 in 2023 and 49,526 in 2022 to 10,296 in 2024 (from September 15 to November 22). On the other hand, Haryana saw a reduction from 2,123 to 1,183. Similarly, in Haryana which has a total of 28 lakh acres under paddy this year, reported only 1,210 incidents till date, against 2,239 of the last year and 3,522 reported in 2022.
However, Hiren Jethva, a senior research scientist at NASA, speculated that some farmers might be burning stubble during the late afternoon or nighttime to evade satellite detection. Citing data from South Korea’s GEO-KOMPSAT-2A satellite, he highlighted smoke plumes observed during these hours, while NASA-NOAA satellites record data between 1:30 pm and 2:00 pm.
“Intense stubble-burning in Punjab, on both sides of the border. AQI/PM2.5 in hazardous category in Delhi (US Embassy Data). Do we need more evidence and proofs to convince policy makers that open field burning is a major, giant source of air pollution during this season?”, he shared a post on his account X.
In another post, sharing images of stubble-burning incidents, he wrote, “Today first time in the season a massive increase in stubble-burning incidence observed around noon to 2 pm, 1,000 fire counts from Suomi-NPP/VIIRS in Punjab alone, very little in Haryana. PM2.5 levels skyrocketed in Delhi reaching 1000µg/m3 sending AQ to hazardous category”, he added.
Following the Supreme Court’s directions to address gaps in farm fire data, government agencies, including the Indian Agricultural Research Institute (IARI) and the National Remote Sensing Centre (NRSC), are working to refine and standardise stubble burn area mapping, sources have revealed.
To enhance data accuracy, the NRSC, ICAR-IARI, and remote sensing centres in Punjab and Haryana have initiated a pilot project during the Kharif season. The initiative utilises the European Sentinel-2 satellite, which provides high-resolution (20-metre) images every five days. These images, encompassing optical, near infrared, and short-wave infrared bands, enable precise mapping of burn scars on agricultural fields.
This improved methodology is expected to fill data gaps, particularly those caused by undercounting biases in existing satellite systems and contribute significantly to addressing stubble-burning and its impact on air quality.
But despite such a huge fall in incidents of farm fires, the atmospheric aerosol pollution (AOD) levels have remained unchanged over the past couple of years.
The environmentalists also raised questions over the authenticity of this data saying, “If stubble-burning incidents have reduced so drastically, why hasn’t the aerosol level dropped.”
They are of the view that there was a difference in assessing the total burnt area, rather than just counting incidents as the governments should assess the burnt areas as well.