NEW DELHI: This Nov is the second most polluted penultimate month ever after 2021. The average air quality index of Nov this year was 375 against 376 in Nov 2021.
This was also the first time in Nov when AQI never fell below 300 in the entire month, according to data from Central Pollution Control Board (CPCB), which started calculating the index in April 2015.
Delhiites witnessed eight ‘severe’ days, including two ‘severe-plus’ days, this month. With no rain providing respite from the toxic pollution, emissions from local and regional sources, along with unfavourable meteorological conditions, led to high pollution levels.
The lowest AQI was 303, which was still in the ‘very poor’ category. The month also witnessed AQI reaching 494 on a scale of up to 500 on Nov 18, making it the second most polluted day ever. On 10 days, AQI was above 390.
Anumita Roychowdhury, executive director of research and advocacy at Centre for Science and Environment, said, “It is a matter of concern that the overall average PM2.5 levels of winter months are upward now. Even though meteorology plays a role, it is necessary to assess how local and regional emissions are increasing, aggravating the winter build-up. This requires very stringent year-round multi-sector action, not only in Delhi, but also in the entire NCR and beyond.”
Last year, the average AQI in Nov was 373. It was 321 in 2022, 328 in 2020, 312 in 2019, 335 in 2018, 361 in 2017, 374 in 2016 and 358 in 2020.
Dipankar Saha, former head of CPCB’s air laboratory, said, “As no strong western disturbance impacted the plains, there was no rain activity in Nov this year. Rain helps in settling down the pollutants. Since Delhi records adverse meteorology in winter months, the focus should be on emissions reductions at the ground.”
The second most polluted Nov came after Oct 2024 recorded the worst air quality since Oct 2020. Delhi’s average AQI was 231 this Oct, making it the highest since 2020, when it was 265. The average AQI was 219 last Oct, 210 in Oct 2022, 173 in Oct 2021, 234 in Oct 2019, 269 in Oct 2018, 285 in Oct 2017, 271 in Oct 2016, and 264 in Oct 2015.
CPCB classifies an AQI between 0 and 50 as ‘good’, between 51 and 100 as ‘satisfactory’, between 101 and 200 as ‘moderate’, between 201 and 300 as ‘poor’, between 301 and 400 as ‘very poor’, and over 400 as ‘severe’.