Noida: After touching the upper levels of the ‘poor' category a day after Diwali, the AQI in the city and Greater Noida improved marginally on Saturday, once again aided by the dispersal of pollutants by a breeze.
With winds likely to slow down, pollution levels may spike over the next few days.
Air quality in the two NCR cities started to deteriorate since Thursday evening as people burst firecrackers till late into the Diwali night. But the presence of a steady surface wind — clocking up a speed of 6-12 kmph — helped clear the pollutants quickly, so much so that post-Diwali air quality in the two cities, though still ‘poor', was the best in the last eight years.
On Saturday, Noida's average AQI was recorded at 269. Though still ‘poor', it was better than Friday's 274 and marginally worse than 257 on Thursday (Diwali). Greater Noida's average AQI was recorded at 250 on the day, better than Friday's 258. On Thursday, AQI was at 253.
Average AQI in Noida's four air quality monitoring stations oscillated in the ‘poor' category but levels of particulate matter (PM) 2.5 – tiny pollutants that are inhaled and can get absorbed into the bloodstream – hit a high of 424ug/m3 – way past the permissible safe limit of 60ug/m3 – at the Sector 62 around 12am on Saturday.
Around the same time, PM2.5 level touched 477 ug/m3 at the Sector 116 station and 396 ug/m3 at the Sector 1 station. Sector 125 station touched the highest PM2.5 level of 391 ug/m3 around 1am on Saturday.
Average AQIs at Greater Noida's Knowledge Park III and V stations were at 247 and 217, respectively. But the granular particles in the air at Knowledge Park III were high at 370 around 3am on Saturday. Knowledge Park V touched 320 at 12am.
Ghaziabad's air quality plummeted further on Saturday. The city's average AQI touched 330 (very poor), up from 306 recorded a day ago and remains in a very poor category. Loni recorded the highest average AQI at 366, followed by Sanjay Nagar at 342 and Indirapuram at 301, all in the ‘very poor' category. Only Vasundhara remained in ‘poor' category at 287.
At 500, PM2.5 levels touched ‘hazardous' levels in Indirapuram, Vasundhara and Sanjay Nagar — the two areas that saw a steady cacophony of crackers on Diwali and then again on Friday — between 11pm on Friday and 3am on Saturday.
A bulletin issued by the Indian Institute of Tropical Meteorology (IITM) stated the predominant surface wind was calm during morning hours and blowing from northwest or northeast direction over Delhi-NCR.
The wind direction is likely to change, blowing from the southeast or east on Sunday, and its speed may drop to 8 kmph. "These conditions may be extremely unfavourable for the dispersion of pollutants," it said.
sector 50 | 1PM