Fig. 4: The temporal evolution of dual-isotope-constrained source contributions from the Monte Carlo (MC) model during China’s decade-long PM2.5 pollution episodes.
From: Unprecedented shifts in aerosol pollution sources in China under a decade of clean air actions
a The comparison of source contributions (biomass, liquid fossil and coal burning) of BC isotope samples collected at Tianjin (BTH) in North China from this 2020–2023 study compared to the previous 2012–2014 studies33,34. b MC-simulated mean source contributions of BC isotope samples collected at Kaifeng in the Central Plains of China from 2021 autumn to 2023 spring. c MC-simulated mean source contributions of BC isotope samples collected at Yantai in the Shandong Peninsula from Dec. 2020–Mar. 2023. d MC-simulated mean source contributions of BC isotope samples collected at Beijing in North China from the previous January 2014 haze study33. e MC-simulated mean source contributions of BC isotope samples collected at Hefei in the western YRD from Apr. 2016–Dec. 2019 (without sampling from Oct. 2017–Nov. 2018). f MC-simulated mean source contributions of BC isotope samples collected at urban Shanghai in January 2014 ref. 33 and 2019 ref. 4, and at YRE ref. 4. (Shanghai Chongming Island) from Dec. 2018–Nov. 2019. The x-axis dates represent the sampling start dates for each individual isotope sample. Each data point corresponds to one specific measurement; see Supplementary Table 8 for detailed sample dates and information. All MC-simulation results are provided in Supplementary Table 8 and the SD for data in (a–f) are provided in Supplementary Fig. 14. The white gap and break are due to the lack of sampling.
