Seasonal characteristics and key sources of trace element deposition fluxes in coastal Poland

Coastal regions are important sources of anthropogenic elements that contribute to climatic, hydrological, and environmental changes. The Baltic Sea basin represents a key domain for exploring air quality issues, where inter-annual variability of various pollutants is notable. Trace element atmospheric dry deposition fluxes were investigated for the first time at a coastal urban site in Poland between April 2019 and May 2020. Atmospheric deposits of As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, and V were calculated using the deposition velocities for coarse-mode particles (PM10), considering different meteorological parameters. Data analysis revealed that Ni and As contributed substantially to more than 30% in winter, indicating a significant impact of specific anthropogenic sources (i.e., industrial combustion and coal combustion for domestic heating). Cr accounted for 19%-33% of the total deposition flux, with its highest contribution in spring. The principal component analysis revealed that primary sources, including road- and soil-related dust resuspension, vehicle exhausts, coal combustion, and the industrial sector, had a substantial influence on the total variation in deposition fluxes. The HYSPLIT analysis identified regions such as the northwestern and western Europe as significant for enhancing atmospheric deposition of trace elements in coastal Poland.