Skip to main content
. 2022 Feb 9;130(2):027004. doi: 10.1289/EHP9406

Figure 4.

Figures 4A, 4B, 4C, and 4D are four bar graphs titled China, the North China Plain, the Yangtze River Delta region, and the Pearl River Delta, respectively, plotting Average daily maximum 8-hour average ozone concentrations (micrograms per meter cubed), ranging from 0 to 150 in increments of 50 (y-axis) across Season, including Spring, Summer, fall, Winter (x-axis), respectively.

Region-specific seasonal mean MDA8 O3 concentrations during 2005–2019 for (A) China as a whole, (B) the North China Plain (NCP), (C) the Yangtze River Delta region (YRD), and (D) the Pearl River Delta (PRD). The O3 concentrations were predicted by the original model with OMI L24 retrievals. The bars and the corresponding numbers represent the season-specific regional mean MDA8 O3 concentrations (±standard deviation) over 2005–2019. Note: Fall, September–October–November; MDA8, daily maximum 8-h average; O3, ozone; OMI, Ozone Monitoring Instrument; spring, March–April–May; summer, June–July–August; winter, December–January–February.