The air quality in Delhi-NCR slipped to "very poor" category on Friday with AQ index at 306 points. The Ministry of Earth Sciences' air quality research and forecast service, SAFAR, said the reason for deterioration of air quality was the "gradual change in weather conditions -- slow surface winds and cooling -- towards unfavourable side". Besides, stubble burning in Haryana, Punjab and western Uttar Pradesh region was also a major factor for alarming spike in pollution, added SAFAR. It is to be noted that the maximum number of stubble burning takes place between October 15 and November 15 in these regions.
The forecast service has said the the share of stubble burning to Delhi's PM 2.5 concentration would be 10 percent on Friday and would increase to 18 per cent on Saturday.
Kuldeep Srivastava, a senior scientist at the India Meteorological said the slow easterly winds, which at present, are blowing in Delhi, are unfavorable for dispersion of pollutants. But, there could be improvement after October 20.
Meanwhile, SAFAR has advised people to avoid their morning walks or any other outdoor activities as poor air quality might led to respiratory difficulties, cough and other diseases.
The overall AQI at DTU, Dwarka Sector 8, Narela, Wazirpur and Bawana was 312, 316, 310, 312, and 341 respectively today, which fall in the "very poor" category.
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'.
(with PTI inputs)