The impact of a long-distance dust storm, localised air pressure systems picking up dust and the westerly direction of surface winds left the city gasping for fresh air Sunday.
The air quality in Delhi and most NCR towns was ‘very poor’ as the concentration of particulate matter in the air increased. The air quality forecast says Monday will be worse, with air quality in the ‘severe’ category.
India Meteorological Department (IMD) officials said the lack of rain in Rajasthan, Himachal Pradesh, Punjab and Delhi has led to dust accumulating in these parts. “Without rain, the possibility of formation and accumulation of dust increases. With the prevailing wind system, where wind is flowing from the dry western parts of the country and a western disturbance over the hills in Himachal Pradesh and Jammu and Kashmir is active, you get dust storm-like conditions,” said an IMD official.
As per the Central Pollution Control Board’s air quality index, the city’s air was in the ‘very poor’ range with an AQI value of 334. In Gurgaon, the AQI was 372 while in Ghaziabad it was 382. The primary pollutants were PM 10 and PM 2.5. IMD officials said the impact of PM 10 was more than that of PM 2.5, which points more to the presence of dust particles.
At the Delhi Pollution Control Committee’s Jawaharlal Nehru Stadium station, for example, the concentration of PM 10 at 8 am was 2,290 micrograms per cubic metres, almost 23 times the standard of 100 micrograms per cubic metres. The concentration of PM 2.5 was 254 micrograms per cubic metres against the standard of 60 micrograms per cubic metres. As winds picked up, the concentration gradually decreased.
With a dust storm expected Monday, the air is expected to get poorer. However, IMD has forecast light rain on Tuesday, which will bring down pollution levels.