Seasonal Evolution of the Chemical Composition of Atmospheric Aerosol in Terra Nova Bay (Antarctica)

• Published in: Atmosphere
• Main Authors: Flavio Vagnoni, Silvia Illuminati, Anna Annibaldi, Francesco Memmola, Giada Giglione, Anna Maria Falgiani, Federico Girolametti, Matteo Fanelli, Giuseppe Scarponi, Cristina Truzzi
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2021
• Subjects: sequential extraction procedure; metals; Antarctic aerosol; seasonal evolution; enrichment factors; Meteorology. Climatology; QC851-999; Antarctic; The Antarctic; Ross Sea; Terra Nova Bay; Mario Zucchelli; Mario Zucchelli Station; Faraglione; Antarc*; Antarctica
• Online Access: https://doi.org/10.3390/atmos12081030; https://doaj.org/article/0bb2a0d9abce427da11fbe49782110fd

Atmospheric aerosol samples were collected at Faraglione Camp, 3 km away from the Italian Mario Zucchelli Station (Terra Nova Bay, Ross Sea), from 1 December 2013 to 2 February 2014. A two-step extraction procedure was applied to characterize the soluble and insoluble components of PM 10 -bound metals. Samples were analyzed for Al, Fe, Cd, Cu, and Pb by square wave anodic stripping voltammetry (SWASV) and by graphite furnace atomic absorption spectrophotometer (GF-AAS). The mean atmospheric concentrations were (reported as means ± SD) Al 24 ± 3 ng m −3 Fe 23 ± 4 ng m −3 Cd 0.92 ± 0.53 pg m −3 Cu 43 ± 9 pg m −3 , and Pb 16 ± 5 pg m −3 . The fractionation pattern was metal-specific, with Al, Fe, and Pb mainly present in the insoluble fractions, Cd in the soluble one, and Cu equally distributed between the two fractions. The summer evolution showed overall constant behavior of both fractions for Al and Fe, while a bell-shaped trend was observed for the three trace metals. Cd and Cu showed a bell-shaped evolution involving both fractions. A seasonal increase in Pb occurred only for the insoluble fraction, while the soluble fraction remained almost constant. Sequential extraction and enrichment factors indicated a crustal origin for Al, Fe, and Pb, and additional (marine or anthropogenic) contributions for Cd and Cu. Back trajectory analysis showed a strong contribution of air masses derived from the Antarctic plateau. A potential low contribution from anthropized areas cannot be excluded. Further studies are necessary to better characterize the chemical composition of the aerosol, to discriminate between natural and anthropogenic sources, and to evaluate a quantitative source apportionment.