Unwatched Pollution: The Effect of Intermittent Monitoring on Air Quality
研究发现，美国《清洁空气法》下每六天一次的空气质量监测周期，导致城市在监测日短期抑制污染，而未监测日空气质量显著恶化，地方政府通过空气质量预警协调减排。
Intermittent monitoring of environmental standards may induce strategic changes in polluting activities. This paper documents local strategic responses to a cyclical, once-every-six-day air quality monitoring schedule under the federal Clean Air Act. Using satellite data of monitored areas, I show that air quality is significantly worse on unmonitored days. This effect is explained by short-term suppression of pollution on monitored days, especially during high-pollution periods when the city’s noncompliance risk is high. Cities’ use of air quality warnings increases on monitored days, which suggests local governments’ role in coordinating emission reductions.