The air quality in the national capital improved to the satisfactory category on Monday with the rainfall on Sunday evening washing down pollutants from local sources and reducing the impact of stubble burning, authorities said.
According to the Central Pollution Control Board, Delhi’s 24-hour average air quality index (AQI) improved from 160 on Sunday to 82 on Monday.
An AQI between zero 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”.
The Ministry of Earth Sciences” forecast agency SAFAR said the air quality is likely to remain in the satisfactory to moderate categories for the next three days.
“As very calm local conditions are unlikely, rapid deterioration is not expected for the next three days… Overall AQI will be in the upper end of satisfactory to the lower end of moderate category for the next three days,” it said.
SAFAR said smoke from stubble burning accounted for 6 percent of Delhi’s PM2.5 pollution.
However, the impact of farm fires on Delhi’s AQI is likely to “increase rapidly” from October 27 due to the highly favourable speed and direction of transport-level winds from Punjab and Haryana and no likelihood of rainfall, it said.
Rainfall and cloudy conditions across northwest India on Sunday kept the number of farm fires down.
According to Indian Agricultural Research Institute (IARI), the number of stubble burning cases reduced from 620 on Saturday to zero on Sunday in Punjab and from 218 to 38 in Haryana.