Using an eight-week long original survey conducted day-by-day in 2015, we leverage daily variation in air quality to estimate the causal effects of pollution on regime support. We test our hypothesis that pollution reduces citizens' assessments of the regime. Our results show that air pollution decreases overall satisfaction at both central and local levels, substantially increases demand for government oversight, and negatively affects perceptions of economic performance. Additionally, we time our survey to partially coincide with a period during which the regime intentionally reduced air pollution, allowing us to exploit this unique instance of authoritarian environmental engineering. We show that government efforts to reduce pollution do successfully improve citizens' evaluations of the regime. This paper provides causal estimates of the importance of environmental challenges in a developing country and sheds light on specific facets of authoritarian governance affected by pollution.