Delhi’s air quality slipped to ‘very poor’ category on Tuesday after strong winds kicked up dust. It is likely to improve slightly to ‘poor’ category on Wednesday.
The PM10 — a chief pollutant — was 140 microgram per cubic metre at 4 a.m. and went up to 775 microgram per cubic metre by 8 a.m. on Tuesday. It was mainly because of strong winds, 30-45 km per hour, prevailing over the area during night, according to the IMD.
Visibility dropped to 1,100 metres on Tuesday morning compared to 4,000 metres on Monday morning.
The Air Quality Index (AQI) of Delhi was 309 (very poor) at 8 p.m. on Tuesday, up from 254 at 4 p.m. on Tuesday and 162 at 4 p.m. on Monday, according to the Central Pollution Control Board (CPCB) data.
A higher value of AQI means an increase in air pollution and a fall in air quality. An AQI between 201 and 300 is ‘poor’, 301 and 400 are termed ‘very poor’, and 401 and 500 ‘severe’.
“The dust raising strong winds since the early morning of May 16 increased the particulate matter concentration significantly. The air quality is likely to remain in the ‘very poor’ category throughout the day. It is likely to remain in the ‘poor’ category on May 17 and 18. The air quality is likely to improve and reach the lower end of the ‘poor’ category on May 19,” according to the central government’s Air Quality Early Warning System for Delhi.
The Commission for Air Quality Management in NCR and adjoining areas (CAQM) said it is an “exceptional episodic event” which has led to continual dispersion of dust in the ambient air over entire Delhi-NCR and is likely to improve in two days. Rain is also expected on Thursday.
