The effect of environmental regulation on population migration: Evidence from China's new ambient air quality standards

Environmental regulations may lead to changes in individual behaviors. This paper investigates the effect of environmental regulations on population migration. Using the new ambient air quality standard (NAAQS) as an event study, the difference-in-differences (DID) strategy is constructed for estimation. We find that, on average, over 18.76 thousand in the net inflow of the permanent population decreases after implementing the NAAQS. The reduction primarily occurs in cities that implement the new standard in the first stage. The mechanism analysis shows the NAAQS both increases the population inflow by improving air quality and reduces it through polluting industry transfer and industrial upgrading. The heterogeneous analyses show that the NAAQS has significantly negative effects on population migration in cities that monitor air quality more strictly, cities located southeast of the Hu Huanyong Line, and cities with higher economic development levels. Conversely, the NAAQS has no significant impact on cities in the northwest of the Hu Huanyong Line and cities with low economic development.