"Political blue sky" in fog and haze governance: evidence from the local major international events in China.

The trade-off between economic development and environmental protection has always been a significant and tough issue for local governments. Studies found that some local governments took temporary measures to control air pollution and created "political blue sky" in certain periods. We collected daily air quality index (AQI) data and individual pollutant concentration data of four cities in China which have hosted major international events in 2019. The air quality of the cities taken temporary measures to control air pollution had an obvious improvement during the events. Furthermore, the improvement mainly occurred in pollution indicators, such as PM and PM, which are more valued and sensitive to the public. The sustainability analysis demonstrates that the air quality deteriorated again after the event, indicating that "political blue sky" comes at the cost of retaliatory pollution.