List of Figures

1. Location of Sevettijärvi, Skreådalen, Birkenes, and Sde Boker measurement sites.
2. Fine sulphur concentration field (ng/m$^3$) as computed using CF method for Sevettijärvi, Sde Boker, Birkenes, and Skreådalen. The location of the sites is indicated with an 'x'.
3. PSCF bootstrapped spatial distribution of fine sulphur at 95% confidence level, with 75-th percentile of the concentration distribution as threshold, for Sevettijärvi, Sde Boker, Birkenes, and Skreådalen. The location of the sites is indicated with an 'x'.
4. PSCF spatial distribution of fine sulphur, with 75-th percentile of the concentration distribution as threshold, for Sevettijärvi, Sde Boker, Birkenes, and Skreådalen. The location of the sites is indicated with an 'x'.
5. Spatial distributions of (top) PSCF and (bottom) bootstrapped PSCF with 75-th percentile as threshold for fine arsenic, at Sevettijärvi, and for fine vanadium, at Sde Boker. The location of the sites is indicated with an 'x'.
6. Spatial distribution of joint probability of source contributions to Sevettijärvi and Sde Boker for fine sulphur. The location of the sites is indicated with an 'x'.
7. CF at Sevettijärvi for fine PM, BC ($\mu$g/m$^3$), Zn, NH$_4^+$, Pb, and NO$_3^-$ (ng/m$^3$). The location of the site is indicated with an 'x'.

Figure 1: Location of Sevettijärvi, Skreådalen, Birkenes, and Sde Boker measurement sites.

Figure 2: Fine sulphur concentration field (ng/m$^3$) as computed using CF method for Sevettijärvi, Sde Boker, Birkenes, and Skreådalen. The location of the sites is indicated with an 'x'.

Figure 3: PSCF bootstrapped spatial distribution of fine sulphur at 95% confidence level, with 75-th percentile of the concentration distribution as threshold, for Sevettijärvi, Sde Boker, Birkenes, and Skreådalen. The location of the sites is indicated with an 'x'.

Figure 4: PSCF spatial distribution of fine sulphur, with 75-th percentile of the concentration distribution as threshold, for Sevettijärvi, Sde Boker, Birkenes, and Skreådalen. The location of the sites is indicated with an 'x'.

Figure 5: Spatial distributions of (top) PSCF and (bottom) bootstrapped PSCF with 75-th percentile as threshold for fine arsenic, at Sevettijärvi, and for fine vanadium, at Sde Boker. The location of the sites is indicated with an 'x'.

Figure 6: Spatial distribution of joint probability of source contributions to Sevettijärvi and Sde Boker for fine sulphur. The location of the sites is indicated with an 'x'.

Figure 7: CF at Sevettijärvi for fine PM, BC ($\mu$g/m$^3$), Zn, NH$_4^+$, Pb, and NO$_3^-$ (ng/m$^3$). The location of the site is indicated with an 'x'.