Why Delhi Looked Less Hazy This Diwali Despite Worse Air Quality

What happened: A Centre for Science and Environment report found Delhi's average PM2.5 concentration in the week before Diwali was 236 micrograms per cubic metre, despite the city appearing less hazy. Key numbers: Pre-Diwali average PM2.5 was 236 ug/m3, almost double the 120 ug/m3 recorded in 2025. It was the highest pre-Diwali average in three years. Why it matters: The report links the higher pre-Diwali pollution average to the gap between how hazy the city looked and its measured air quality.

A Centre for Science and Environment report found Delhi's average PM2.5 concentration in the week before Diwali was 236 micrograms per cubic metre, despite the city appearing less hazy.

The report links the higher pre-Diwali pollution average to the gap between how hazy the city looked and its measured air quality.