Cyclone Hamoon increases air pollution in Chennai

CHENNAI: Even as the Cyclone Hamoon crossed Bangladesh on Wednesday, the wind pattern impacted by the cyclone has increased the concentration of air pollutants over Chennai for the last three days.

As per the Tamil Nadu Pollution Control Board (TNPCB) data, the average air quality index (AQI) in Chennai was recorded at 109 on October 23. This increased to 121 on October 24 and 127 on October 25 (Wednesday). As of 6 am on Thursday, the AQI was recorded 121.7 in Chennai.

K Srikanth, weather blogger based in the city, explained that due to the cyclone in the Bay of Bengal, wind is flowing to the city from north, which is from the land surface. “Wind flowing from the north is slow and could not disperse the pollutants from the city. This phenomenon is common during the winter season,” he said.

He added that when the wind starts flowing from the east, once the cyclone weakens further, the pollutants will be dispersed and the level of pollution will come down. It may be noted that the cyclone has already weakened resulting in rains in northeastern states.

Further, he clarified that not all cyclones in Bay of Bengal impact wind from and increase pollution.

Among the 7 monitoring stations, Manali recorded an AQI of 192 on Thursday morning and Perungudi recorded an AQI of 152. AQI in Kodungaiyur and Arumbakkam was 119 and 111 respectively. AQI was comparatively lower in Alandur (104), Royapuram (103), and Velachery (71). As per norms, AQI less than 50 is categorized as good and 51 to 100 is considered satisfactory. AQI between 101 – 200 and 201-300 is categorized as moderate and poor.

Meanwhile, the TNPCB has decided to conduct awareness campaigns on air pollution caused due to bursting of crackers as Diwali festival is only a few days away.