Acetic acid leachable trace metals from bulk aerosol samples collected during the US GEOTRACES EPZT section cruise (R/V Thomas G. Thompson TN303) in the Eastern Tropical Pacific from October to December 2013

Abstract

Atmospheric input is important to the biogeochemical cycling of trace metals in the ocean. The fraction of aerosol trace metals that can potentially dissolve after deposition is of interest for improving knowledge of aerosol/surface ocean interactions. This dataset provides acetic acid leachable trace metal values from bulk aerosol from the Equatorial Pacific along the US GEOTRACES EPTZ transect (TN303) from Peru to Tahiti. This region is characterized as one of the lowest atmospheric deposition regimes in the ocean. Bulk aerosols were collected from the boundary layer (~15 m above sea level) using a high-volume aerosol sampler drawing approximately 1.2 cubic meters of air per minute over Whatman 41 ash-less filter discs. Despite low aerosol loadings, triplicate agreement for most samples was good for Al, Ti, V, Mn, Fe, and Cu. Away from the coast, Cd and Pb values in most samples were close to, or below detection limit. Acetic acid leaches were carried out with a combination of 25% acetic acid and a reducing agent. Leachable trace metal concentrations were determined at the University of Alaska Fairbanks by inductively coupled plasma mass spectrometry (Thermo Element-2) using external calibration curves. The aerosol trace metal fractional solubility was calculated as a percent of the total bulk aerosol data from the same cruise (https://www.bco-dmo.org/dataset/675632).

For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/709276