Modification of the Conversion of Dimethylsulfide to Methanesulfonic Acid by Anthropogenic Pollution as Revealed by Long-Term Observations

• Main Authors: Bei Jiang (665589), Zhouqing Xie (1572910), Yue Qiu (1521598), Longquan Wang (10340091), Fange Yue (10340088), Hui Kang (579945), Xiawei Yu (10340097), Xudong Wu (720962)
• Format: Other Non-Article Part of Journal/Newspaper
• Language: unknown
• Published: 2021
• Subjects: Physiology; Biotechnology; Ecology; Science Policy; Space Science; Environmental Sciences not elsewhere classified; Biological Sciences not elsewhere classified; Chemical Sciences not elsewhere classified; Physical Sciences not elsewhere classified; marine boundary layer; contrasting atmospheric environments; arctic ocean promoted; term observations since; increased dms emissions; 3 </ sub; term observations; together inhibited; principal factors; oxidation product; northwest pacific; methanesulfonic acid; intensively investigated; claw hypothesis; bering sea; anthropogenic pollution; anthropogenic activities; air masses; aerosols derived; Arctic; Arctic Ocean; Bering Sea; Pacific
• Online Access: https://doi.org/10.1021/acsearthspacechem.1c00222.s002

Since the CLAW hypothesis was proposed approximately three decades ago, aerosols derived from dimethylsulfide (DMS) conversion have been intensively investigated. In this study, long-term observations were conducted for methanesulfonic acid (MSA), the oxidation product of DMS, from 2008 to 2016 in the marine boundary layer of the Bering Sea. We found that (1) the increase in sea surface temperatures led to increased DMS emissions and MSA concentrations; however, (2) air masses from different sources caused significant differences in the conversion efficiencies of DMS to MSA; and (3) air masses with high O 3 and NO 2 , low relative humidity, temperature, and cloud liquid water path from the northwest Pacific, which were influenced by anthropogenic activities, together inhibited the conversion of DMS to MSA. Among them, O 3 , T2M, and RH were the principal factors. Conversely, air masses, with contrasting atmospheric environments, from the Arctic Ocean promoted the conversion of DMS to MSA.