Fig. 1.

(A) Varying levels of mean concentrations of daily 1-h maximum ozone from December 10, 2019 to February 12, 2020 by spatial interpolation with inverse distance weighting. (B) Spatial distribution of basic reproductive number (R₀) across 154 Chinese cities. (C) Estimated nonlinear relationships and corresponding confidence intervals between the R₀ and daily 1-h maximum ozone concentrations in the multivariable regression analysis with two weighting schemes (equal-weighted and weighted by the number of cases). The violin plot on the left of the panel C indicates the distribution of R₀, and the violin plot at the bottom shows the distribution of ambient 1-h maximum ozone concentrations; their interquartile ranges are represented by the black rectangle, their medians are indicated by the white square, and the distribution of values was shown by the light-blue area.