Atmospheric inputs of volcanic iron around Heard and McDonald Islands, Southern Ocean

Atmospheric deposition of iron (Fe) to anaemic waters in the Southern Ocean (SO) can relieve marine phytoplankton growth limitation. This study reports measurements of enhanced Fe loading to the atmosphere around and up to 500 km downwind from Heard and McDonald Islands, on the Kerguelen plateau. Characteristic Fe-to-Aluminum (Al) signature and volcanic tracer enrichments (molybdenum, chromium, and nickel) in the same aerosols when compared to local igneous rock measurements, suggested that atmospheric Fe originated from the volcanic eruption of Big Ben on Heard Island. Our results foster better characterization of the volcanic Fe emissions to the atmosphere and promotes the inclusion of volcanic inputs into modelling representation of the impact of aeolian Fe deposition on remote marine ecosystems.

Reference: Perron, M. M. G., Proemse, B. C., Strzelec, M., et al. (2021). Atmospheric inputs of volcanic iron around Heard and McDonald Islands, Southern Ocean. Env. Sci.: Atm. https://doi.org/10.1039/D1EA00054C.