Long-term Monitoring of Dust Falling to the Ocean

Aeolian dust from  Southern Hemisphere sources was shown to support at least one-third of the Southern Ocean primary productivity. In this study, analysis of aluminum, iron, thorium, and titanium contained in aerosols was used to provide a multi-tracer field-based estimate of the dust deposition flux variability at kunanyi / Mount Wellington in lutruwita / Tasmania (Australia) between 2016 and 2021. Our lithogenic flux estimates were consistent with known climatological features, showing maxima during the austral summer following the Australian dust storm season, and annual minimum deposition flux over winter. Time-series field observations as provided in our study are essential to help validating model estimates of Southern Hemisphere atmospheric deposition fluxes and their subsequent impact on the Southern Ocean's carbon cycle.

Reference: Hird, C., Perron, M.M.G., Holmes, T., et al. (2024). On the use of lithogenic tracer measurements in aerosols to constrain dust deposition fluxes to the ocean southeast of Australia. Aerosol Res., 2, 315-327. https://doi.org/10.5194/ar-2-315-2024