Sea breeze gives Mumbai cleanest Diwali air in four years, AQI still moderate

Mumbai recorded its cleanest Diwali afternoon air in four years on Sunday, with the Air Quality Index (AQI) standing at 131 around 1 pm, according to the Central Pollution Control Board (CPCB).

The reading was lower than the Diwali afternoon AQI recorded in the previous three years. The city recorded 194 in 2025, 181 in 2024, and 149 in 2023.

However, the AQI of 131 falls in the CPCB's 'moderate' category, which can cause breathing discomfort among people with lung diseases, asthma and heart conditions. This is the fourth consecutive Diwali that Mumbai has remained in the moderate category.

Atmospheric scientist Gufran Beig, chair professor at the National Institute of Advanced Studies (NIAS), attributed the relatively lower pollution levels to strong sea breezes.

"Over the past 48 hours, a wind reversal has taken place due to which the sea breeze is blowing at a high speed. This phenomenon has somehow controlled the concentration of pollutants in the air, leading to the overall readings appearing to be little lesser. A few days back, we saw the same thing happening in Delhi as well," Beig told The Indian Express.

He attributed the wind reversal mainly to fluctuations in El Niño conditions.

"Tomorrow (November 9) the AQI may further plummet because today everyone will burst firecrackers and the residue of the pollutant will continue to linger in the air," Beig said.

Mumbai's air quality had already begun deteriorating in the first week of October. Firecracker emissions are expected to push pollution levels higher after Diwali celebrations.

On Sunday, 20 of the city's 26 monitoring stations recorded AQI readings above 100. Bandra East (Kherwadi) recorded the highest reading at 195, followed by Shivaji Nagar (Mankhurd) at 183, Bandra Kurla Complex at 173, Ghatkopar at 170, Chembur at 168, and Mazgaon at 133.