Chandigarh: At 270, AQI shoots up to season’s worst

After showing improvement towards the end of last week, the city’s Air Quality Index (AQI) has worsened again, shooting up to 270 on Monday, the highest so far this season.

Officials attributed stubble burning in neighbouring Punjab and Haryana as the biggest cause for the rising pollution, while also citing bursting of crackers and the changing weather conditions as other reasons.

Though bursting of green crackers is allowed on Diwali, unchecked bursting of crackers is already taking place, leading to pollution. Other factors impacting the AQI include vehicle exhaust fumes and road dust.

The air quality was worst at the Continuous Ambient Air Quality Monitoring Station (CAAQMS) in Sector 53, which borders Mohali, touching 270 at 2 pm on Monday. AQI went past 250 at the Sector-22 CAAQMS as well, while air quality was also poor at the Sector 6 observatory in Panchkula.

An AQI between 201-300 can cause breathing discomfort to most people on prolonged exposure.

The AQI graph had first crossed 200 in the city on October 20, before hitting 250 on October 23.

Thereon, it dropped below 200, which the India Meteorological Department (IMD) officials said was due to the effect of Cyclone Dana in the Bay of Bengal.

Member secretary of Chandigarh Pollution Control Committee, TC Nautiyal said they were monitoring the situation and if it worsened, they will send out advisories to other departments of the UT administration and the municipal corporation as well.

Chandigarh has a Graded Response Action Plan (GRAP) for air pollution. This has different levels to it, and while the earlier levels involve sending advisories, if the air remains in the severe category (AQI over 400) for over two days, for the next two days, the administration can decide to enforce measures, which includes shutting down schools, stopping construction work and using sprinklers in the city.

Decreasing temperatures may worsen air quality

AQI is also considerably affected by the temperature, and once the night temperature starts falling, temperature inversion occurs, which keeps pollutants from dispersing, thereby increasing AQI.

Currently, the temperature is still on the higher side. The maximum temperature rose from 31.4°C on Sunday to 32.1°C on Monday, 3.3 degrees above normal. Even the minimum temperature increased from 18.9°C on Sunday to 19.2°C on Monday, 5.1 degrees above normal.

Speaking about this, IMD Chandigarh director Surender Paul said, “The temperature continues to remain above average because of low rainfall during this month. Dry and sunny skies are keeping the temperature from sliding. Rain is not likely in the city anytime soon as of now.”

Over the next three days, the maximum temperature will remain between 31°C and 32°C, and the minimum temperature around 19°C.