Cross-state air pollution transport calls for more centralization in India's environmental federalism

Ambient air pollution kills over four million people every year globally. Improving air quality presents a complex problem for governments as emissions are produced from a wide range of sources and tend to cross boundaries. To understand the challenge of transboundary air pollution transfer, we use a detailed emissions inventory and a source-oriented chemical transport model to explore state-to-state flows of emissions within the world's largest democracy, India, where poor air quality has caused a public health crisis. On average, 46% of population-weighted air pollution exposure originates from another state. Of the major sources, energy (75%) and industry (53%) see most of their emissions travel to another state. All sectors have 39% or more of their emissions travel across state boundaries. India's current policy framework is not equipped to deal with these problems, as it does not centralize the formulation and enforcement of relevant policies sufficiently. To solve the problem of air pollution, India needs a more centralized form of environmental federalism.