Although official data shows a sharp fall in the stubble burning incidents in the northern states this season, experts have raised doubts about the accuracy of the data gathered via satellite surveillance, and pointed out loopholes in the system.
Sources said current practice of capturing firm fires using foreign satellites is flawed because it does not capture the real incidents. There are limited windows for capturing data which farmers have started to avoid. Officials on the condition of anonymity said that mapping of actual “burnt areas” in the field does not match with satellite imaging.
“Farmers have altered their burning schedules to avoid detection by satellite monitoring systems although there is no official confirmation of this yet,” a source from the scientific community said, requesting anonymity.
Chandra Bhushan, CEO, International Forum for Environment, Sustainability, and Technology ( iFOREST) said that while as per the official data, the number of farm fires fallen have sharply in the last couple of years while the Aerosol Optical Depth, which measures the concentration of particulates in the atmosphere, has remained unchanged over Punjab and Haryana.
“We need to have re-look at the method of data capturing of fire events. There is a need to assess the burnt area which would indicate a much clearer picture,” Bhusan told FE.
During September 15 – November 18, the total of 27,319 firm fire events reported as per Consortium for Research on Agro-ecosystem Monitoring and Modeling from Space (CREAMS) in northern states of Punjab, Haryana, Uttar Pradesh, Rajasthan, Madhya Pradesh and Delhi, were down 46% on year.
Out of which Punjab which has a share of 35% in total fire cases are from Punjab. Stubble burning in Punjab has dropped 71% on year to 9655 this period, as per the data.
However, the new lows of air quality witnessed in the national capital region (NCR) during last many days would raise doubts about the claim that crop residue burning by farmers has reduced to this extent. Firm fires contribute about 38% of the total pollution in the Delhi-NCR, according to officials, which means, combined with other polluting activities like vehicle transport and construction, it could be a major contributor of the deterioration of air quality in early winter, when the atmospheric moisture causes materials to remain suspended in the air.
Meanwhile, according to the central pollution control board, the measured air quality index (AQI) on Monday was measured at ‘severe’ level at 494. AQI between 401-500 is considered as ‘severe’ while index of 301-400 fall under ‘very poor’ category. An AQI of 201-300 belongs to ‘poor’.
The Indian Institute of Tropical Meteorology (IITM) forecast conditions are likely to remain extremely unfavourable for effective dispersion of pollutants in the Delhi and adjoining areas. “The air quality is likely to be in ‘severe’ category from November 19 – November 21,” IITM has stated in its forecast.
The Commission for Air Quality Management has imposed GRA – stage 4 in Delhi-NCR on Sunday. following a surge in AQI to “severe” levels.