Open AccessIron speciation and mixing in single aerosol particles from the Asian continental outflow
Author(s) -
Moffet Ryan C.,
Furutani Hiroshi,
Rödel Tobias C.,
Henn Tobias R.,
Sprau Peter O.,
Laskin Alexander,
Uematsu Mitsuo,
Gilles Mary K.
Publication year - 2012
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2011jd016746
Subject(s) - mineral dust , aerosol , environmental chemistry , soot , sulfate , coal combustion products , chemical composition , environmental science , particle (ecology) , combustion , carbon fibers , flux (metallurgy) , atmospheric sciences , solubility , mineralogy , chemistry , materials science , geology , metallurgy , oceanography , organic chemistry , composite number , composite material
Bioavailable iron from atmospheric aerosol is an essential nutrient that can control oceanic productivity, thereby impacting the global carbon budget and climate. Particles collected on Okinawa Island during an atmospheric pollution transport event from China were analyzed using complementary single particle techniques to determine the iron source and speciation. Comparing the chemical composition and spatial distribution of iron within ambient particles and standard Asian mineral dust, it was determined that field‐collected atmospheric Fe‐containing particles have numerous sources, especially anthropogenic sources such as coal combustion. Fe‐containing particles were found to be internally mixed with secondary species such as sulfate, soot, and organic carbon. The mass weighted average Fe(II) fraction (defined as Fe(II)/[Fe(II) + Fe(III)]) was determined to be 0.33 ± 0.08. Within the experimental uncertainty, this value lies close to the range of 0.26–0.30 determined for representative Asian mineral dust. Previous studies have indicated that the solubility of iron from combustion is much higher than that from mineral dust. Therefore, chemical and/or physical differences other than oxidation state may help explain the higher solubility of iron in atmospheric particles.