NEW DELHI: Just two days ahead of Diwali, the national capital recorded its worst air quality of the season on Monday, with pollution levels inching towards “severe plus emergency” category due to a change in wind direction and rampant stubble burning in neighbouring states.
The PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) and PM10 concentrations touched 365 and 503 respectively, touching the “severe-plus emergency” category, according to Central Pollution Control Board (CPCB) data.
Delhi’s overall air quality index on Monday was recorded at 434, which falls in the “severe” category, a drastic decline from Sunday’s “moderate” level at 171.
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”.
In NCR, Faridabad, Ghaziabad, Noida and Greater Noida recorded “severe” pollution levels while Gurgaon recorded “very poor” air quality, CPCB data showed.
Officials attributed the sudden deterioration in the air quality to a change in wind direction, which is now blowing from the northwestern region towards Delhi and bringing dust and smoke from stubble burning in neighbouring states with it.
A thick haze has engulfed the national capital two days ahead of Diwali, following which, experts have warned, the air quality is likely to worsen further due to local factors.
On Sunday, Delhiites had breathed the cleanest air in three weeks, according to CPCB data. The air quality turned severe for the first time this season on October 30.
Officials attributed the sudden deterioration to a change in wind direction, now blowing from the northwestern region towards Delhi, bring with it dust and smoke from stubble burning in neighbouring states.
CPCB chairman S.P. Singh Parihar said the deterioration of the air quality will continue till Tuesday morning.
“But the good news is that speed of surface wind has improved, which may help in dispersing the pollutants,” he said.
The CPCB has called a meeting of transport department to discuss the deteriorating air quality in the national capital.
