Chemical Composition of Aerosol over the Arctic Ocean from Summer ARctic EXpedition (AREX) 2011–2012 Cruises: Ions, Amines, Elemental Carbon, Organic Matter, Polycyclic Aromatic Hydrocarbons, n-Alkanes, Metals, and Rare Earth Elements

Atmosphere

卷:10

Rita Traversi¹  Silvia Becagli¹  Cristiana Rizzi²  Luca Ferrero²  Marco Cataldi²  Giorgia Sangiorgi²  MariaGrazia Perrone²  Ezio Bolzacchini²  Tomasz Petelski³  Tymon Zielinski³  Przemysław Makuch³  Paulina Pakszys³  Piotr Markuszewski³ 

[1] Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019 Sesto F. no, Florence, Italy;

[2] GEMMA and POLARIS Research Centre, Department of Earth and Environmental Sciences, University of Milano-Bicocca, 20126 Milan, Italy;

[3] Institute of Oceanology, Polish Academy of Sciences, 81-712 Sopot, Poland;

关键词: aerosol;    Arctic Ocean;    inorganic ions;    carboxylic acids;    amines;    elemental carbon;    organic carbon;    polycyclic aromatic hydrocarbon;    n-alkanes;    elements;    Svalbard;   

DOI  :  10.3390/atmos10020054

来源: DOAJ

【 摘 要 】

During the summers of 2011 and 2012, two scientific cruises were carried out over the Arctic Ocean aiming at the determination of the aerosol chemical composition in this pristine environment. First, mass spectrometry was applied to study the concentration and gas/particle partitioning of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes. Experimental and modelled data of phase partitioning were compared: results demonstrated an equilibrium between gas and particle phase for PAHs, while n-alkanes showed a particle-oriented partitioning, due to the local marine origin of them, confirmed by the extremely low value of their carbon preference index. Moreover, the inorganic and organic ions (carboxylic acids and amines) concentrations, together with those of elemental carbon (EC) and organic matter (OM), were analyzed: 63% of aerosol was composed of ionic compounds (>90% from sea-salt) and the OM content was very high (30.5%; close to 29.0% of Cl⁻) in agreement with n-alkanes’ marine signature. Furthermore, the amines’ (dimethylamine, trimethylamine, diethylamine) concentrations were 3.98 ± 1.21, 1.70 ± 0.82, and 1.06 ± 0.56 p.p.t.v., respectively, fully in keeping with concentration values used in the CLOUD (Cosmics Leaving OUtdoor Droplet)-chamber experiments to simulate the ambient nucleation rate in a H₂SO₄-DMA-H₂O system, showing the amines’ importance in polar regions to promote new particle formation. Finally, high resolution mass spectrometry was applied to determine trace elements, including Rare Earth Elements (REEs), highlighting the dominant natural versus anthropic inputs for trace metals (e.g., Fe, Mn, Ti vs. As, Cd, Ni) and possible signatures of such anthropic activity.

【 授权许可】

Unknown