Abstract
To investigate the characteristics of particulate methanesulfonic acid (MSA<span classCombining double low line"inline-formula">(p)</span>), non-sea-salt sulfate (nss <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M2" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msubsup><mi mathvariantCombining double low line"normal">SO</mi><mn mathvariantCombining double low line"normal">4</mn><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>-</mo></mrow></msubsup></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"29pt" heightCombining double low line"17pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"74b4be02f6bf1e477b176a208786a61b"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"acp-20-5405-2020-ie00001.svg" widthCombining double low line"29pt" heightCombining double low line"17pt" srcCombining double low line"acp-20-5405-2020-ie00001.png"/></svg:svg></span></span>) and organic carbon (OC) aerosols, aerosol and seawater samples were collected over the Southern Ocean (43-70<span classCombining double low line"inline-formula">ĝˆ</span> S) and the Amundsen Sea (70-75<span classCombining double low line"inline-formula">ĝˆ</span> S) during the ANA06B cruise conducted in the austral summer of 2016 aboard the Korean icebreaker IBR/V Araon. Over the Southern Ocean, the atmospheric MSA<span classCombining double low line"inline-formula">(p)</span> concentration was low (<span classCombining double low line"inline-formula">0.10±0.002</span> <span classCombining double low line"inline-formula">μ</span>g m<span classCombining double low line"inline-formula">-3</span>), whereas its concentration increased sharply up to 0.57 <span classCombining double low line"inline-formula">μ</span>g m<span classCombining double low line"inline-formula">-3</span> in the Amundsen Sea where Phaeocystis antarctica (P. antarctica), a producer of dimethylsulfide (DMS), was the dominant phytoplankton species. Unlike MSA<span classCombining double low line"inline-formula">(p)</span>, the mean nss <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M12" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msubsup><mi mathvariantCombining double low line"normal">SO</mi><mn mathvariantCombining double low line"normal">4</mn><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>-</mo></mrow></msubsup></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"29pt" heightCombining double low line"17pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"97cb19aa5ca8b26a6d7fd7d4bad307d2"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"acp-20-5405-2020-ie00002.svg" widthCombining double low line"29pt" heightCombining double low line"17pt" srcCombining double low line"acp-20-5405-2020-ie00002.png"/></svg:svg></span></span> concentration in the Amundsen Sea was comparable to that in the Southern Ocean. Water-soluble organic carbon (WSOC) concentrations over the Southern Ocean and the Amundsen Sea varied from 0.048 to 0.16 and 0.070 to 0.18 <span classCombining double low line"inline-formula">μ</span>gC m<span classCombining double low line"inline-formula">-3</span>, with averages of <span classCombining double low line"inline-formula">0.087±0.038</span> and <span classCombining double low line"inline-formula">0.097±0.038</span> <span classCombining double low line"inline-formula">μ</span>gC m<span classCombining double low line"inline-formula">-3</span>, respectively. For water-insoluble organic carbon (WIOC), its mean concentrations over the Southern Ocean and the Amundsen Sea were <span classCombining double low line"inline-formula">0.25±0.13</span> and <span classCombining double low line"inline-formula">0.26±0.10</span> <span classCombining double low line"inline-formula">μ</span>gC m<span classCombining double low line"inline-formula">-3</span>, varying from 0.083 to 0.49 and 0.12 to 0.38 <span classCombining double low line"inline-formula">μ</span>gC m<span classCombining double low line"inline-formula">-3</span>, respectively. WIOC was the dominant organic carbon species in both the Southern Ocean and the Amundsen Sea, accounting for 73 %-75 % of the total aerosol organic carbon. <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M25" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><mi mathvariantCombining double low line"normal">WSOC</mi><mo>/</mo><msup><mi mathvariantCombining double low line"normal">Na</mi><mo>+</mo></msup></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"62pt" heightCombining double low line"14pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"12dae9807fce924696370d5f814c6d36"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"acp-20-5405-2020-ie00003.svg" widthCombining double low line"62pt" heightCombining double low line"14pt" srcCombining double low line"acp-20-5405-2020-ie00003.png"/></svg:svg></span></span> and <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M26" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><mi mathvariantCombining double low line"normal">WIOC</mi><mo>/</mo><msup><mi mathvariantCombining double low line"normal">Na</mi><mo>+</mo></msup></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"58pt" heightCombining double low line"14pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"65d1d9da7da5fef8d6eccf2d81244993"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"acp-20-5405-2020-ie00004.svg" widthCombining double low line"58pt" heightCombining double low line"14pt" srcCombining double low line"acp-20-5405-2020-ie00004.png"/></svg:svg></span></span> ratios in the fine-mode aerosol particles were higher, especially in the Amundsen Sea where biological productivity was much higher than the Southern Ocean. The fluorescence properties of water-soluble organic aerosols investigated using a fluorescence excitation-emission matrix coupled with parallel factor analysis (EEM-PARAFAC) revealed that protein-like components were dominant in our marine aerosol samples, representing 69 %-91 % of the total intensity. Protein-like components also showed a significant positive relationship with the relative biomass of diatoms; however, they were negatively correlated with the relative biomass of P. antarctica. These results suggest that the protein-like component is most likely produced as a result of biological processes of diatoms in the Amundsen Sea.
.Original language | English |
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Article number | 2020 |
Pages (from-to) | 5405-5424 |
Number of pages | 20 |
Journal | Atmospheric Chemistry and Physics |
Volume | 20 |
Issue number | 9 |
DOIs | |
State | Published - 8 May 2020 |