Aerosol-associated trace metals are potential sources of bio-limiting nutrients in the open ocean. There are a limited number of observations of atmospheric trace metals and their bioavailability over the southern hemisphere, and limited observations over the Atlantic sector of the Southern Ocean. To understand the potential impact of atmospheric trace elements, aerosol samples were collected following the GEOTRACES cookbook during the GApr23 cruise. We observed minimal mineral dust loads of 37.4 ± 14.5 ng/m³, while the concentrations of all trace elements such as Fe, Mn, Cu, Cr, Cu, Ni, Pb were less than 100 pmol/m³. The calculated enrichment factors for Fe and Mn are close to crustal values, while Cr, Ni, Cu, Zn, and Pb are enriched relative to upper continental sources, suggesting a contribution from anthropogenic emissions for these metals. The fractional solubilities of these trace metals span a wide range, from Fe = 6.1 ± 4.6 %, to Mn = 30.9 ± 28 % and Cu = 35 ± 16.2 %. The strong westerlies enhance atmospheric mixing and acid processing, leading to high fractional solubility of some of the trace elements. We therefore conclude that atmospheric processing of dust is a key determining factor of trace metal fractional solubility during austral summer over the Southern Ocean compared to other possible drivers such as mixing with anthropogenic emissions.  

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