Delhi set to see most polluted December in four years: Here’s why
As Delhi’s air quality stood on the brink of the ‘severe’ category on Saturday, the average AQI for December is set to be the worst from 2019 onwards. The average AQI for the month, till December 30, was 346. On Saturday, the 24-hour average AQI at 4 pm was 400, close to the ‘severe’ category, according to data from the Central Pollution Control Board (CPCB). The average AQI for the month is worse than it has been in recent years – in 2022, the average for December was 319, while it was 336 in 2021, 332 in 2020, and 337 in 2019. The last time a higher average was recorded was in 2018 – 360. Inversion and slow winds are normal winter phenomena. The volume of activities — vehicles, industrial activities and waste burning in the entire region – all of this is contributing to the trend, showing us that in the coming year, round-the-year action will have to be scaled up significantly to be able to address this issue. As activities increase, action has to keep pace with that change,” Roychowdhury said. Gufran Beig, founder project-director SAFAR, and chair professor, National Institute of Advanced Studies, pointed to another factor that could be keeping pollution levels higher – large-scale circulation patterns. “In general, large-scale circulation patterns have reduced the surface wind speed. Last year, these patterns – the La Nina phenomenon – resulted in an increase in wind speed that dispersed pollutants and brought cleaner-than-usual air to Delhi in December,” he said.
