Millions of Indians are breathing in the world’s most toxic air. Each winter, thick smog envelops the capital of New Delhi and numerous cities across the dusty and densely populated North Indian plains. Chief Minister Arvind Kejriwal, the leader of the metropolis that’s home to 20 million people, called New Delhi a “gas chamber.” An estimated 1.1 million people died as a result of air pollution in India in 2015, according to the non-profit Health Effects Institute. The air has since gotten worse.
Vehicle and industrial emissions contribute year-round, as do road and construction dust and domestic fires lit by the poor. But a grim extra wallop comes late in the year from the burning of crop stubble, which continues despite being banned in the surrounding states of Punjab, Uttar Pradesh, Haryana and Rajasthan. Farmers traditionally clear fields by burning in preparation for the winter season. Compounding the problem: The trough-like topography of north India means polluted air lingers in colder months.