The Energy and Resources Institute (TERI) has found that 74% of ultrafine particles(PM2.5) in Delhi’s air come from outside the city during summer. Mostly particles polluting Delhi comes from NCR, other small towns nearby Delhi and beyond even from as far as Pakistan,Afghanistan and Oman. Which states that Delhi generates only around 26% of its own pollution.
The proportions change and around 64% of the city’s pollution comes from external sources in winters. Out of it, around 13% pollution comes from outside India.
Delhi also contributes to 40% pollution in Noida and 15% in Gurugram during winter. The two satellite towns are located in Delhi’s downwind path. Whereas Panipat is located on the upwind path of Delhi and receives only 1% pollution from Delhi.