The air quality of Delhi and Noida was in ‘very poor’ category on Saturday and Gurugram’s was in ‘poor’ category, according to the Central Pollution Control Board (CPCB) data.
The national capital’s air quality is expected to improve slightly in the coming days. “Due to better ventilation conditions, the AQI is forecast to marginally improve to the lower end of ‘very poor’ during the day. AQI is likely to stay in ‘very poor’ category on January 24 and 25. The middle end of ‘very poor’ category is forecast,” said a statement by the government-run monitoring agency SAFAR.
Also, the speed of surface-level winds was “moderate”, which aided in lesser accumulation of pollutants near the surface. However, the “mixing layer height”, which is the height from the ground level up to which pollutants can be dispersed, was “low”. This also led to accumulation of pollutants near the surface.
The AQI of Delhi was 326 on Saturday, as per CPCB’s 4 p.m. bulletin, which is an average of the past 24 hours. The values for Gurugram and Noida were 285 and 325 respectively.
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’.
