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Covid-19, city lockdowns, and air pollution: evidence from China

The rapid spread of Covid-19 is a global public health challenge. To prevent the escalation of its transmission, China locked down one-third of its cities and strictly restricted personal mobility and economic activities. Using timely and comprehensive air quality data in China, we show that these counter-Covid-19 measures led to a remarkable improvement in air quality. Within weeks, the Air Quality Index and PM2.5 concentrations were brought down by 25%. The effects are larger in colder, richer, and more industrialized cities. We estimate that such improvement would avert 24,000 to 36,000 premature deaths from air pollution on a monthly basis.

Lead investigator:

Guojon He


Hong Kong University of Science and Technology

Primary topic:

Science, technology & innovation

Region of data collection:

Asia and Oceania

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Status of data collection


Type of data being collected:

Publicly available

Unit of real-time data collection


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