Martin and Zhang (2020) show that the increase in manufacturing output in China's special economic zones significantly increased air pollution. In this complementary paper, we document that widespread migration into these industrial clusters between 2000 and 2010 did little to change overall population exposure to pollution. We show using satellite air pollution data that there is much heterogeneity across zones and that most population growth occurred in relatively cleaner zones, supporting recent literature that documents local willingness to make location decisions based on environmental quality (Chen et al. 2019, Khanna et al. 2020).
