Delhi’s air quality improves 11% after Diwali, but relief may be short-lived

Delhi AQI has started worsening as farm fires rise

Delhi’s air became slightly cleaner after Diwali, with pollution levels easing as the city’s average Air Quality Index (AQI) dropped 11 percent in the week following the festival compared to the Diwali period.

According to a Moneycontrol analysis of pollution data from the past 11 years, such post-Diwali relief is not unusual. In five of those years (2016, 2017, 2020, 2021, and 2025), the average AQI in the week after Diwali was lower than on the festival day itself.

This year, Delhi’s average AQI stood at 348 on Diwali day and dropped to 309 over the following nine days.

The improvement comes even as the Delhi government faced criticism from the opposition for allegedly manipulating AQI data and underreporting pollution levels.

However, data shows that such short-term declines are often weather-driven.

Satellite data suggest that the respite may be temporary, with paddy-residue burning — a key seasonal driver of smog — beginning to pick up again across northern India.

In the seven days ending October 30, Punjab recorded 906 fire events, up from 828 during the same period last year. Uttar Pradesh also reported a modest rise, from 231 to 256 fires, while Haryana logged 35 cases, roughly half of last year’s count but showing a slight late-October uptick.

While Delhi breathed marginally easier this week, historical patterns suggest that air quality improvements after an October Diwali are short-lived.

With farm fires expected to intensify in early November and winter inversion setting in, pollution levels are likely to climb again.

Delhi’s AQI was a high 373 on October 30, as per CPCB numbers.