Can India leapfrog into a clean air future – perspectives from measurements, source-receptor modelling and emission inventories

India struggles with frequent exceedances of the ambient air quality standard for particulate matter, ozone and benzene. The situation in the Indo-Gangetic plain (IGP) is particularly severe during post monsoon and winter season.

We show that despite strong governmental efforts to make clean energy accessible and affordable, residential solid fuel usage is still the largest source of particulate matter pollution and carcinogenic benzene in India. Particularly cow dung as a cooking and heating fuel contributes disproportionally to the residential sector emissions and India’s air quality challenge. In addition, crop residue burning, open burning of waste, solid fuel usage in industrial boilers, and power generation units also contribute significantly to the particulate matter and benzene emissions over the region. In urban agglomerations, transport sector emissions aggravate the already poor air quality further.

In this talk we present several recently updated gridded emission inventories with detailed VOC speciation for these air pollution sources. We also look at future projection under different Shared Socioeconomic Pathways (SSPs) for several sources.

We focus on the most polluted part of the year, namely post-monsoon and winter season, to evaluate and compare these updated emission inventories against other available emission inventories and measurements studies. We find that that existing inventories tend to underestimate the magnitude of residential sector emissions and their strong seasonality. The use of solid fuels for heating purposes results in a strong temperature induced emission feedback that can aggravate the wintertime fog. Existing inventories also underestimate the magnitude of crop residue burning emissions and lack open waste burning as a source.

A combination of measurement-based assessments and emission inventories for different air quality intervention strategies are used to evaluate a number of possible air quality interventions for their potential impact. We specifically look at the sectoral coupling between the residential sector, waste management, crop residue management, and the transport sector to propose interventions that maximize air quality gains.