Does Sea Spray Aerosol Contribute Significantly to Aerosol Trace Element Loading? A Case Study From the US GEOTRACES Pacific Meridional Transect (GP15) Academic Article uri icon

abstract

  • AbstractAtmospheric deposition represents a major input for micronutrient trace elements (TEs) to the surface ocean and is often quantified indirectly through measurements of aerosol TE concentrations. Sea spray aerosol (SSA) dominates aerosol mass concentration over much of the global ocean, but few studies have assessed its contribution to aerosol TE loading, which could result in overestimates of new TE inputs. Lowmineral aerosol concentrations measured during the U.S. GEOTRACES Pacific Meridional Transect (GP15; 152W, 56N to 20S), along with concurrent towfish sampling of surface seawater, provided an opportunity to investigate this aspect of TE biogeochemical cycling. Central Pacific Ocean surface seawater Al, V, Mn, Fe, Co, Ni, Cu, Zn, and Pb concentrations were combined with aerosol Na data to calculate a recycled SSA contribution to aerosol TE loading. Only vanadium was calculated to have a SSA contribution averaging >1% along the transect (mean of 1.5%). We derive scaling factors from previous studies on TE enrichments in the sea surface microlayer and in freshly produced SSA to assess the broader potential for SSA contributions to aerosol TE loading. Maximum applied scaling factors suggest that SSA could contribute significantly to the aerosol loading of some elements (notably V, Cu, and Pb), while for others (e.g., Fe and Al), SSA contributions largely remained <1%. Our study highlights that a lack of focused measurements of TEs in SSA limits our ability to quantify this component of marine aerosol loading and the associated potential for overestimating new TE inputs from atmospheric deposition.

published proceedings

  • GLOBAL BIOGEOCHEMICAL CYCLES

altmetric score

  • 0.25

author list (cited authors)

  • Marsay, C. M., Landing, W. M., Umstead, D., Till, C. P., Freiberger, R., Fitzsimmons, J. N., ... Buck, C. S.

citation count

  • 0

complete list of authors

  • Marsay, Chris M||Landing, William M||Umstead, Devon||Till, Claire P||Freiberger, Robert||Fitzsimmons, Jessica N||Lanning, Nathan T||Shiller, Alan M||Hatta, Mariko||Chmiel, Rebecca||Saito, Mak||Buck, Clifton S

publication date

  • August 2022