Dicarboxylic and Oxocarboxylic Acids in the Arctic Coastal Ocean (Beaufort Sea‐Mackenzie Margin). Issue 7 (24th July 2019)

• Record Type: Journal Article
• Authors: Sempéré, Richard; Vaïtilingom, Mickael; Charrière, Bruno; Kawamura, Kimitaka; Panagiotopoulos, Christos
• Is Part Of: Global biogeochemical cycles. Volume 33:Issue 7(2019:Jul.)
• Page Start: 927
• Page End: 940
• Publication Date: 2019-07-24
• Subjects: Arctic Ocean -- Mackenzie River -- bifunctional carboxylic acids -- anthropogenic signatures -- organic matter; Biogeochemical cycles -- Periodicals; Electronic journals; 577.1405
• DOI: 10.1029/2018GB006165
• Languages: English
• ISSNs: 0886-6236

Abstract

Abstract: The distribution of bifunctional carboxylic acids (BCAs) is largely reported as primary or secondary organic aerosols. However, sparse studies describe the distribution of these organic compounds in fluvial and marine environments. In the context of a global warming, we present the first results of a study of the distribution of BCAs in a surface Arctic coastal area near the mouth of the Mackenzie River. These results showed that the Beaufort Sea is an area with elevated BCA content among which glyoxylic acid is predominant, in contrast to low concentrations and predominance of oxalic acid in aerosols reported elsewhere. The carbon fraction of BCAs represents 1.8% to 4.5% of dissolved organic carbon pool in Arctic Ocean. This study reinforces the hypothesis that aquatic biological processes govern the molecular distribution of BCA in marine/river waters, whereas photochemical oxidation reactions regulate their molecular distribution in rain and aerosols. Our results indicate that the Mackenzie River is an important source of BCAs in the Arctic Ocean during July–October period, with a first estimate of 35 × 10 3 tons of BCAs including 12 × 10 3 tons of diacids and 23 × 10 3 tons of oxoacids. Key Points: Here we present the first results of a study of the distribution of BCAs (including dicarboxylic and oxoacids) in a surface Arctic Ocean Arctic Rivers provide large amount of BCA to the Arctic Ocean, a process that might be increased with global warming BCAs have been recognized as major water soluble organic compounds that potentially may act for a part as cloud condensation nuclei (CCN)