Gurugram air quality may enter ‘severe’ category during weekend

Experts and officials have warned that Gurugram’s air quality might enter the ‘severe’ category over the next day or two.

A day after the city breathed its best air since Diwali, pollution rose once again on Thursday. By weekend, air pollution may even enter the ‘severe’ category, officials and experts said, adding that the condition could be like that on November 3, when the air quality index (AQI) value touched 486—the highest this season.

Smog over Delhi-Gurugram expressway, Gurugram,, on Thursday, November 07, 2019. (Parveen Kumar / HT PHoto)

Air quality in the city stood at 284 (poor) on the Central Pollution Control Board’s daily AQI bulletin, up from 164 (moderate) the previous day. The average level of PM2.5 pollutants also increased from 167ug/m3 on Wednesday to 267ug/m3 on Wednesday (at 7pm).

Experts and officials attributed the deterioration to light showers, slow winds and an overcast sky. Thursday was also marked by a dip in temperature, showed data of the India Meteorological Department, which played a significant role in the accumulation of pollutants. They warned that the air quality might enter the ‘severe’ category over the next day or two.

According to SAFAR’s early air quality warning system for the national capital region (NCR), “The air quality is likely to deteriorate and may remain in ‘very poor’ category on 08.11.2019. The air quality is likely to improve marginally on 09.11.2019 and may remain in poor to lower end of very poor category.” The predicted AQI for Gurugram on Friday is 231, in the ‘poor’ category. However, experts said the results could change depending on fluctuations in meteorology.

“When the sun warms the earth’s surface, suspended particles rise. When the sky is cloudy, penetration of sunlight does not happen, so temperatures drop and pollutants settle much closer to the earth,” Sachin Panwar, a city-based air quality scientist, said.

“The same phenomenon had happened last weekend. The air quality had improved last Saturday due to improvement in wind speed, followed by light showers in the evening, leaving remaining pollutants trapped under cloud cover,” said a senior scientist at CPCB’s air quality lab in Delhi.

Also, inadequate rain led to formation of heavier particles in the air, which could not be dispersed by slow winds at low temperatures leading to emergency-level of air pollution on November 3 (when city AQI touched 486). Similar conditions are likely to occur once again on Friday, experts said.