Sources of anions in aerosols in northeast Greenland during late winter

Marlene Fenger Lauridsen, Lise Lotte Sørensen, Kasper Kristensen, Bjarne Jensen, Quynh Nguyen, Jacob Klenø Nøjgaard, Andreas Massling, Henrik Skov, Thomas Becker, Marianne Glasius

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Abstract

The knowledge of climate effects of atmospheric
aerosols is associated with large uncertainty, and a better understanding of their physical and chemical properties is needed, especially in the Arctic environment. The objective of the present study is to improve our understanding of the processes affecting the composition of aerosols in the high Arctic. Therefore size-segregated aerosols were sampled at a high Arctic site, Station Nord (Northeast Greenland), in March 2009 using a Micro Orifice Uniform Deposit Impactor. The aerosol samples were extracted in order to analyse three water-soluble anions: chloride, nitrate and sulphate. The results are discussed based on possible chemical and physical transformations as well as transport patterns. The total concentrations of the ions at Station Nord were 53–507 ngm−3, 2–298 ngm−3 and 535–1087 ngm−3 for chloride (Cl−), nitrate (NO−3 ) and sulphate (SO2−
4 ), respectively. The aerosols in late winter/early spring, after polar sunrise, are found to be a mixture of long-range transported and regional to local originating aerosols. Fine particles, smaller than 1 μm, containing SO2−4 , Cl− and NO−
3 , are hypothesized to originate from long-range transport, where SO2−4 is by far the dominating anion accounting for 50–85% of the analyzed mass. The analysis suggests that Cl− and NO−3 in coarser particles (> 1.5 μm) originate from local/regional sources. Under conditions where the air mass is transported over sea ice at high wind speeds, very coarse particles (> 18 μm) are observed, and it is hypothesized that frost flowers on the sea ice are a source of the very coarse nitrate particles.
Original languageEnglish
JournalAtmospheric Chemistry and Physics
Volume13
Pages (from-to)1569-1578
ISSN1680-7316
DOIs
Publication statusPublished - 2013

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