Smog engulfs Kolkata on Sunday night
Kolkata: Kolkata’s ambient air quality deteriorated sharply on Kali Puja-Diwali Sunday night as rampant bursting of firecrackers pushed fine particulate pollution to hazardous levels across the city from 9 pm. Because kali Puja falls unusually late this year, with a wintry chill already setting in, the deterioration was particularly alarming. Environmentalists warned that falling night-time temperatures and atmospheric temperature inversions could trap toxic pollutants close to the ground and prolong their impact well beyond the period of bursting.
Central Pollution Control Board (CPCB) data showed that after recovering in the afternoon, the parameters — mainly PM2.5 and PM10 — started deteriorating again after 6 pm on Sunday. At Salt Lake, the PM2.5 sub-index jumped from 117 at 4 pm on Saturday to 330 by 11 pm, before peaking at 336 at 1 am. Ballygunge recorded a rise from 148 at 4 pm to 321 at 11 pm, while Jadavpur climbed from 159 to 326 during the same period. readings remained elevated at 5 am, indicating that the pollutant load had not fully dispersed Although pollution levels began declining before dawn at several monitoring stations.
At 9 pm on Sunday, all the seven air quality monitoring stations in Kolkata reported “moderate” air quality with Ballygunge and Jadavpur already inching towards “poor”. Residents said a burning smell filled the air in many places, and a haze had enveloped their neighbourhoods from the smoke emitted by crackers. The air quality decline was sharp. Hourly pollution data captured the scale of the spike.
Environmentalist Somendranath Ghosh warned that the impact of cracker pollution could outlast the celebrations.