The study shows that air pollution in India changes with the seasons, and each pollutant behaves differently. Tiny particles like PM2.5 and PM10 are highest in winter, while gases like ozone and nitrogen dioxide tend to rise in summer.

The smog is blamed for thousands of premature deaths each year and is an annual source of misery for the capital's residents, with various piecemeal government initiatives failing to measurably address the problem.