Fumes from crop stubble burning led to doubling of its contribution in Delhi's PM 2.5 pollution load to 22 percent on October 17 from 11 percent the previous day
Delhi's air quality remains in the 'poor' category with stubble burning causing a rise in pollution levels on October 17.
The share of stubble fumes in the national capital's PM 2.5 load doubled to 22 percent on October 17 from 11 percent the previous day, Hindustan Times reported citing the Air Quality Early Warning System for Delhi.
Delhi's air quality index (AQI) on October 17 was recorded at 287 in the poor category, according to the Central Pollution Control Board (CPCB) bulletin.
An AQI between 0 and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor', and 401 and 500 'severe'.
"A ventilation index of 10,000 m2/s was recorded during the day time. But at night, the wind is calm and the temperature is low. The ventilation index also falls. Air pollution levels didn’t deteriorate further only because there was wind in the daytime. The wind direction is north-westerly and will continue to remain so for the next couple of days. Stubble fires will impact Delhi’s air," said Vijay Soni, a scientist at IMD (air quality management division), as quoted by the paper.
A ventilation index lower than 6,000 sqm/second, with average wind speed less than 10 kmph, is unfavourable for dispersal of pollutants.
Data from the Indian Council of Agricultural Research (ICAR) showed that action against stubble fires has not been as widespread this year, the report said.
Only 9,000 subsidised straw management machines were distributed to farmers in Punjab this year, as against roughly 51,000 machines distribute in Punjab and Haryana in the previous two seasons.
"Less than half of the machines that were to be made available have actually reached the farmers. I cannot tell you why this has happened but the money has already been given to states for distribution of machinery," Trilochan Mohapatra, director-general, ICAR told Hindustan Times.(With inputs from PTI)