Vehicles and transport emissions contributed 19% to Delhi’s PM2.5 pollution on the day of the festival, November 8
Pollution can spike sharply in the case of fireworks, but vehicles are one of the biggest contributors to the city’s everyday PM2.5 burden. Vehicles were the single largest contributor to the city’s PM2.5 pollution on Oct. 24, accounting for 25%. Secondary organic aerosols contributed 18.4 %, followed by secondary inorganic aerosols (16.5 %), road dust (10.9 %) and waste burning (5 %). Vehicles and transport emissions contributed 19% to Delhi’s PM2.5 pollution on the day of the festival, November 8, the largest identified source, estimated the IITM’s Decision Support System (DSS). The Delhi Pollution Control Committee’s data reported on November 9 showed that at Akshardham the PM2.5 concentration was at 760.99 micrograms per cubic meter at 11pm. This was an hourly reading, not a 24 hour average, but gives an idea of how intense the spike of pollution was.
Every year, Delhi’s Diwali pollution debate is between two sources: firecrackers and vehicles. But the latest pollution data suggests the problem is more complex. Diwali fireworks add to existing pollution The Indian Institute of Tropical Meteorology (IITM) has set up a new Integrated Atmospheric Chemistry and Aerosol Toxicity Analysis Laboratory (AATAL), which gives a useful picture of Delhi’s pollution mix. Even around Diwali the transport contribution was still substantial. The figure explains why vehicular pollution cannot be seen as a seasonal problem: unlike fireworks, traffic emissions persist throughout the year. The effect was visible on the night of Diwali.
