Dust Deposition to the Sargasso Sea: A Comparison of Estimates Using Aluminum in the Surface Ocean Versus Aerosols and Rainwater
Year: 2025
Type: article
Abstract: As a major component of mineral aerosol that partially dissolves in seawater, aluminum (Al) has been used to estimate time‐averaged dust fluxes to the ocean, based on dissolved aluminum (DAl) concentrations and an assumed replacement time of DAl (τDAl) in the surface mixed layer, along with the fractional solubility (Als) and mass abundance of Al in dust. We apply this method in the Bermuda region using seasonal water‐column DAl concentrations, and compare our results with fluxes estimated from Al measured in Bermuda aerosols and rain. Inventories of DAl over the maximum mixed‐layer depth of 200 m and empirically derived Als values yield mean dust fluxes of 5.3–11.2 g m−2 yr−1, around 4‐ to 9‐fold higher than fluxes estimated from aerosols and rain, which average 1.2 g m−2 yr−1 over a 318‐day sampling period. This discrepancy likely reflects an underestimate in τDAl and lateral transport of DAl in the surface ocean.
Source: Geophysical Research Letters
DOI: 10.1029/2024gl113217
Institutions: Old Dominion University, Oregon State University, University of South Florida St. Petersburg, Bermuda Institute of Ocean Sciences, Skidaway Institute of Oceanography, University of Georgia, National Oceanic and Atmospheric Administration, University of Washington, NOAA Pacific Marine Environmental Laboratory, Cooperative Institute for Climate, Ocean, & Ecosystem Studies, Bigelow Laboratory for Ocean Sciences, University of Liverpool
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,190
Awards: NSFGEO-NERC: Collaborative Research: Using Time-series Field Observations to Constrain an Ocean Iron Model, NSFGEO-NERC: Collaborative Research: Using Time-series Field Observations to Constrain an Ocean Iron Model, Collaborative Research: Are Low-Temperature Hydrothermal Vents an Important but Overlooked Source of Stabilized Dissolved Iron to the Ocean?, NSFGEO-NERC: Collaborative Research: Using Time-series Field Observations to Constrain an Ocean Iron Model, NSFGEO-NERC: Collaborative Research: Using Time-series Field Observations to Constrain an Ocean Iron Model, NSFGEO-NERC: Collaborative Research: Using Time-series Field Observations to Constrain an Ocean Iron Model, Operation of a Community Marine-Atmospheric Sampling Facility at Tudor Hill, Bermuda
OpenAlex ID: W4409869980