The AQI of Wuhan City decreased significantly, the higher the population density, the more significant the decline.• NO 2 decreased most in Wuhan, but O 3 increased significantly, and Hubei Province also had the same trend. • The mobile source emission ratio and the local pollution contribution in Wuhan decreased.

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The evolution of the COVID-19 pandemic features the alternation of oscillations and abrupt rises. The oscillations are attributable to weekly and seasonal modulations, while abrupt rises are stimulated by mass gatherings.

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