The motivation for the workshop: Aerosol labile iron (LFe), the fraction of total aerosol iron that contributes to the dissolved Fe (DFe) inventory of the ocean, is a crucial source of the micronutrient Fe to the remote marine environment. Current models for the ocean biogeochemical cycling of Fe assume that after deposition to the surface ocean, all aerosol-LFe gets chelated by “free” marine organic ligands and gets converted to DFe. Yet laboratory studies and numerical simulations have shown that after deposition to the ocean only a small fraction of LFe may be chelated by marine organic ligands and enter the DFe pool. This happens because the free ligand concentration in the dust-affected region of the ocean gets quickly exhausted and the short lifetime of inorganic LFe in seawater does not allow for replenishment of organic ligands by the surface ocean vertical mixing and/or biological production and release. The efficiency of LFe to DFe conversion is one of the major unknowns for the global biogeochemical cycling of Fe.

This workshop is dedicated to an improved understanding of how does bioaccessible LFe move across the ocean-atmosphere interface and become bioavailable for uptake in the ocean at scales important for ocean ecosystems and the carbon cycle.

Goals and expected outcomes of the workshop: 1) A white paper that will provide a workshop assessment report based on the consensus reached by diverse researchers from the oceanographic and atmospheric science communities with backgrounds in the laboratory and in situ measurements, modeling, and remote sensing, and 2) a breakout session at AGU 2021 fall meeting to disseminate the workshop findings to the wider research community interested in the global biogeochemical cycling of iron.

We thank DOE, SOLAS and SCOR for providing financial support for the Iron Workshop.

For questions regarding the meeting please contact Nicholas Meskhidze (NC State University) or Bill Landing (Florida State University)

We look forward to seeing many of you in Asheville!