Fig. 3: Contributions of individual sources to atmospheric fine particulate matter (PM2.5) and its components from 2001–2023.
From: Blockchain-based isotopic big data-driven tracing of global PM sources and interventions
a, b, c, d The source composition of PM2.5 and its components in the worldwide (a) Asia (b) the Americas (c) and Europe (d). The labels CC, BB, VE, LFF, IOC, NS, BP, WM, NEE, LE, VF, and WI are abbreviations for coal combustion, biomass burning, vehicle exhausts, liquid fossil fuels combustion, industrial oil combustion, natural soil, biological process, waste materials, non-exhaust emissions, livestock emissions, volatilized fertilizer, and waste incinerator, respectively. Biological processes include plant debris, fungal bacteria, pollen, particulate matter generated by the oxidation of biogenic volatile organic compound emissions, microbial processes. The uncertainties for these results are provided in the Source Data file. For the specific calculation process, see the “Methods” section. Note: in the isotopic source tracing analysis of OC in PM2.5, the liquid fossil fuels combustion is classified as a subdivided source, while OC emissions from vehicle exhaust are not double-counted. Due to the absence of the δ¹⁵N values for ammonia from biomass burning in the Americas and Europe, the global source apportionment study relied on the δ¹⁵N values for ammonia from Asian biomass burning to estimate global values.
