Delhi air quality remains 'severe' for third day 

NEW DELHI: Delhi’s air quality continued to remain in the ‘severe’ zone for the third consecutive day on Sunday, as intense stubble burning activity in neighbouring Punjab and Haryana continued to bring clouds of smoke to the city and the surrounding region. With winds picking up speed, a slight improvement in the pollution levels is likely over the next three days, said government agencies.

As per the Central Pollution Control Board (CPCB), Delhi’s overall air quality index (AQI) on Sunday was 428, against 437 the previous day. The city has been reeling under ‘severe’ air quality since November 5 when post-Diwali fireworks and peak stubble burning activity pushed the pollution levels in the higher end of the ‘severe’ zone, posing a serious health risk to those with respiratory problems as well as the general population at large.

The Centre’s air quality and weather forecasting system in its Sunday forecast said that AQI is likely to improve by Sunday evening, as winds have picked up pace, but will continue to fluctuate between the lower end of severe and the higher end of very poor zones. 

“Currently, air quality is still in severe category because of the large influx of stubble related pollutants which appears to be due to much higher effective fire count observed than that assumed for forecasting. Strong winds coming from the northwest direction are favourable resulting in significant transport of stubble related pollutants to Delhi. This effect is offset by local dispersion of pollutants by moderate surface winds. The total fire count today has reduced to 3,313 from over 4,000 the day before,” it said.

According to officials in the India Meteorological Department (IMD), daytime winds continued to blow from west to northwest over Delhi at a speed of 8-10kmph, which can help dispersion of pollutants concentrated in the year. “Also, visibility further improved to 1200 to 2200m at the IGI and Safdarjung airports on Sunday, which means there was enough sunlight available and will help in improving air quality over the next three days,” said a senior IMD scientist.

He added that night temperature is likely to drop further over next week to 13 degrees C. “A dip in temperature is not favourable for dispersion of pollutants, which is one of the major factors for poor air quality during the winter,” he said.

On Sunday, temperatures were at maximum 29 degrees C and minimum 14 degrees C, normal for this time of year. Satellite images from the NASA fire tracker showed clouds of smoke covering the northwest region. “The emissions from farm fires could be seen enveloping the northwest region,” said Pawan Gupta, a research scientist at the Goddard Earth Sciences Technology and Research (GESTAR), Universities Space Research Association (USRA).