The air quality of national capital Delhi has been subject to unremitting deterioration, but the authorities of the city have reported that there was an “unusual improvement” in the air quality of Delhi on Sunday – improving from “very poor” to just “poor”.

The officials of System of Air Quality and Weather Forecasting (SAFAR) released the latest overall air quality index (AQI) on Sunday and it was recorded at 232 – which falls in the ‘poor’ category. As per the data provided by the Central Pollution Control Board (CPCB) on Sunday, three areas of Delhi still remains under ‘very poor’ air quality category, whereas “unusual improvement” was recorded in 21 regions and the air quality improve to “poor”. SAFAR officials said that this was an “unusual improvement” in the air quality of Delhi, especially for this time of the year. And the betterment is due to sudden increase in wind speed which turned out to be favourable for dispersion of pollutants.