Abstract
This data includes total and soluble Fe concentrations in aerosol samples and particle size data for aerosol samples using a Coulter Counter or Nanoparticle Tracking Analysis from the manuscript “Composition and plume gas interaction control iron fractional solubility more than particle size in volcanic ash: Implications for fertilization of the North Atlantic”
Deposition of volcanic ash is thought to impact marine biogeochemical cycling by adding soluble iron (Fe) to the surface ocean. The magnitude of this input is a function of the amount of ash deposited, the total Fe content in the ash, and ash-derived Fe’s fractional solubility. However, the relative importance of chemical composition, acidic processing by the volcanic plume, and ash particle size in determining solubility is unclear. We paired an aerosol leach meant to provide an upper limit for fractional Fe solubility with chemical analyses of ash from the Cumbre Vieja and La Soufrière eruptions, which both impacted the North Atlantic in 2021. Fe in the ash samples is <6% soluble, but Fe fractional solubility in Cumbre Vieja ash is approximately triple that of La Soufrière ash. Compared to La Soufrière, a larger proportion of the Fe in Cumbre Vieja ash is in silicate rather than oxide minerals, which release more soluble Fe. Elevated levels of surficial fluorine (F) also suggest that Cumbre Vieja ash was subjected to a more fluorine-rich eruption plume and underwent more acidic processing. Particle size does not appear to be a primary control on Fe release. We estimate that the Cumbre Vieja eruption had a much larger impact on dissolved Fe (DFe) concentration in the surface ocean than the La Soufrière eruption due to differences in soluble Fe content and particle deposition velocity. These differences may help explain why some eruptions elicit a biological response in the ocean while others do not.
This data is associated with the article: Elliott, H.E., Blades, E., Royer, H.M., Buck, C., Kollman, C., Kukkadapu, R., China, S., Cheng, Z., Lata, N.N., Engelhard, M., Bowden, M., Lahiri, N., Parham, R.L., Meagher, L., Angstman, B., Ault, A.P., Hornby, A., Dayton, K., Gazel, E., Gaston, C.J. Composition and plume gas interaction control iron fractional solubility more than particle size in volcanic ash: Implications for fertilization of the North Atlantic.