No relief yet, Chandigarh's air quality remains 'poor'
Chandigarh, November 9
The air quality in the city continued to remain in the “poor” category for the second day on Thursday. The Air Quality Index (AQI) was recorded at 214, causing breathing discomfort to residents, especially the aged, children and patients. Experts have advised such people to exercise caution and cut exposure to outdoor activities.
Earlier on Sunday, for the first time in this season, the average AQI of the city dropped to 205 due to changing weather, vehicular emissions and incidents of farm fires in neighbouring areas.
According to the Central Pollution Control Board, around 9pm, the AQI shot up to 239 at the Air Quality Monitoring Station (AQMS) at Sector 53, which is near Mohali, while AQMS, Sector 22, recorded the AQI at 209 and it touched the level of 193 at the AQMS, Sector 25.
An official of the Chandigarh Pollution Control Committee has attributed the condition to the rising incidents of farm fires on the city’s outskirts and weather condition where temperature drops and air remains stagnant.
Also, the average PM-10 level stood at 175 and PM 2.5 at 239 at AQMS, Sector 53. Similarly, the Sector 22 AQMS registered PM-10 at 197 and PM2.5 at 209. At the AQMS, Sector 25, PM-10 stood at 146 and PM-2.5 at 193.
Dr Ravindra Khaiwal, Professor of Environment Health at the Department of Community Medicine, PGIMER, said the city’s AQI was mainly influenced by vehicular activity, which had increased in the last few days, leading to a rise in exhaust and re-suspension of dust.
The contribution of burning of crop residue mainly depended on prevailing wind directions, but its contribution remained less than other sources in the city, he said, adding that atmospheric boundary layer height also lowered to nearly 600 m due to cold weather, which helped build air pollution close to the grounds.
“With the onset of winter, this layer has descended to a lower altitude compared to its usual height of 10-12 km above earth’s surface. This change, which depends on local meteorological factors, has a direct and immediate effect on the AQI,” he added.