Year: 2025
Type: article
Abstract: . The chemical processing (“aging”) of mineral dust is thought to increase dust light scattering efficiency, cloud droplet activation, and nutrient solubility. However, the extent of African dust aging during long-range transport to the western Atlantic is poorly understood. Here, we explore African dust aging in wintertime samples collected from Barbados when dust is transported at lower altitudes. Ion chromatography (IC) analysis of bulk nitrate, sulfate, and oxalate increase when African dust reaches Barbados, indicating dust aging. However, aerosol mixing state analysis from computer-controlled scanning electron microscopy with energy dispersive x-ray spectroscopy (CCSEM/EDX) indicates that approximately 67 % of dust particles are internally mixed with sea salt, while only about 26 % of dust particles contain no internally mixed components. SEM/EDX elemental mapping and time-of-flight secondary ion mass spectrometry (TOF-SIMS) reveals that within internally mixed dust and sea salt particles, only sea salt components contain signs of aging.
Authors: Haley M. Royer, Michael T. Sheridan, Hope E. Elliott, Edmund Blades, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Zihua Zhu, Andrew P. Ault, Cassandra J. Gaston
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,725
Awards: G1202769797, G125460123, G2506945562, G2510423872, G2820049545, G2988778103, G5373841109, G5653134238, G6464524557, G6671297155, G7560550554, G7947320051, G8011145372, G8171135661, G821644656, CAREER: Characterizing African Dust Aging and Seasonal Contributions of Dust and Biomass Burning to Aerosol Biogeochemical Cycles
OpenAlex ID: W4411213685