Fig. 1.

The 12 selected regions in the Northern Hemisphere for source-tagging. The colors in the map represent annual mean BaP emissions from wildfires averaged from 2001 to 2020. The red triangle represents the sampling sites with time series used to compare with modeled BaP concentrations in Fig. S4c. The 12 regions are Southeast Asia (SEAs), Southern Asia (SAs), Eastern Asia (EAs), Mid-eastern Asia (MEAs), Northern Asia (NAs), Northern Africa (NAf), Southern Europe (SEu), Northern Europe (NEu), Tropical America (TAm), Middle North America (MNAm), Northern North America (NNAm), and the Arctic (Arc).