Using a mobile laboratory, M. Bauer et al. captured highly resolved spatial patterns of particulate matter across urban areas in Sarajevo, Bosnia and Herzegovina, revealing pollution levels and gradients that are invisible to fixed monitoring stations. The measurements show pronounced neighbourhood-scale variability and extreme wintertime pollution, reflecting the strong influence of local emission sources in the region.
Crucially, the study goes beyond mapping pollution hotspots by applying source apportionment to the mobile dataset. This analysis disentangles the contributions of key sources such as residential solid-fuel heating, traffic, and cooking activities, providing clear insight into what drives elevated particulate matter concentrations in Sarajevo. The work highlights how robust source apportionment tools, such as those implemented through SoFi, are essential for transforming rich, complex measurement data into actionable understanding of air pollution sources; a critical step for designing effective mitigation strategies in regions facing severe air quality challenges.