The CSE study released here today is based on real-time data on source contribution from the Decision Support System for Air Quality Management of the Indian Institute of Tropical Meteorology (IITM) in Pune.
It said, “The analysis clearly shows vehicles' contribution is half or more. This is followed by household pollution (12.5-13.5%), industry (9.9-13.7%), construction (6.7-7.9%), waste burning and road dust (each varied between 4.6-4.9% and 3.6-4.1%, respectively).”
The Decision Support System of IITM is part of the Air Quality Early Warning System and provides information on potential emission sources in Delhi. It also tracks data from sources outside Delhi -- 19 districts in the national capital region - along with biomass burning in neighbouring states.
During November 2-6, contribution of pollution sources in NCR dominated initial phase, going up to 70-80%.
Similarly, contribution of biomass burning from other states remained low in initial pre-Diwali phase but peaked post-Diwali. Clearly, the calm conditions during the smog episode post-Diwali have reduced intrusion of cross-boundary movement from NCR and enhanced the share of local pollution in Delhi, the CSE said.
“Clearly, after the closure of all coal-based power plants, expansion of natural gas usage in industry and controls on dirty fuels, vehicles have emerged as the biggest real-time contributor among the local sources of winter pollution in Delhi this year. Action on transportation has to gather strong momentum. At the same time, action on waste management, clean energy access in households, and dust control must be speeded up,” Anumita Roychowdhury, executive director, research and advocacy, CSE, said.