NEW DELHI: The national capital’s air quality deteriorated marginally and was recorded in the “poor” category on Wednesday as a change in the wind direction increased the share of stubble burning in the city’s pollution slightly.
The city’s air quality index (AQI) was recorded in the “moderate” category in the morning. However, pollution levels increased by a bit as the day progressed. The 24-hour average AQI stood at 211. It was 171 on Tuesday.
Weather experts and government agencies said no significant change was likely in the next three to four days. V K Soni, the head of the IMD’s environment research centre, said northwesterly winds increased the stubble burning contribution slightly on Wednesday.
According to the Ministry of Earth Sciences’ air quality monitor, SAFAR, stubble burning accounted for 8% of Delhi’s PM2.5 pollution on Wednesday. It was three per cent on Tuesday.
Around 800 fire points were observed in Punjab, Haryana and western Pakistan. However, their impact on Delhi-NCR’s air quality will not be significant, Soni said. The AQI is again going to improve to the “moderate” category by Friday owing to favourable wind speed, he said.
The central government’s Air Quality Early Warning System for Delhi also said Delhi-NCR’s air quality is likely to remain in the “moderate” and the lower end of the “poor” category on Thursday and Friday.
On Wednesday, the prominent surface wind direction was northwesterly and the maximum wind speed 10 km/hr, it said. The minimum and maximum temperatures settled at 10.6 degrees Celsius and 25.4 degrees Celsius respectively.
The IMD said the minimum temperature in Delhi is predicted to drop to 9 degrees Celsius by Saturday, as cold winds have started blowing from hilly regions, which have witnessed a fresh bout of snowfall.