Lithogenic Particle Flux to the Subantarctic Southern Ocean: A Multi‐Tracer Estimate Using Sediment Trap Samples

Mineral dust is a key source of essential micronutrients, particularly iron (Fe), for phytoplankton in the Southern Ocean. However, observations deposition over Ocean are sparse, hindering assessments its influence on marine biogeochemistry. We present time series (2010-2019) lithogenic particle flux estimates using sediment trap samples collected at 1000 m depth subantarctic Time Series (SOTS) site. Lithogenic was estimated individual Fe, aluminium (Al), titanium, and thorium concentrations particles less than 1 mm size. These tracers showed good agreement with one another, their average investigated as proxy mineral deposition. This multi-tracer exhibited strong seasonality, peaking late spring summer. No significant Fe enrichment observed compared to upper continental crust, indicating that material dominates particulate SOTS. Similar Fe:Al ratios our those reported aerosols off southern Australia, coupled trajectory analysis, suggested Australian constitutes primary SOTS sinking particles. Lead also highlighted an anthropogenic contribution particles, which might represent additional aeolian more bio-available waters. study contributes new long-term estimate fluxes may enhance model representation trace metal biogeochemical processes article protected by copyright. All rights reserved.