Stubble burning not major contributor to Delhi's pollution on October 19
On October 19, nearly 68% of Delhi's PM2.5 air pollution actually drifted in from outside the city, according to the Decision Support System (DSS).
Local sources—particularly vehicles—made up about 32%.
Surprisingly, stubble burning only added around 2% that day, showing there's more to Delhi's smog than just farm fires.
Transport biggest polluter in Delhi
A significant portion of the external pollution came from nearby NCR regions like Gautam Buddh Nagar, Gurugram, and Ghaziabad, though the largest share was from unaccounted sources labeled as "others."
Within Delhi, transport was the biggest polluter at over 16%, followed by homes at just over 4%.
Past studies back this up: traffic and burning stuff for fuel are big problems every winter.
All this highlights why tracking where pollution comes from really matters if we want cleaner air.