Phys.org November 27, 2024
Ocean-emitted dimethyl sulfide (DMS) is a major source of climate-cooling aerosols. However, most of the marine biogenic sulfur cycling is not routed to DMS but to methanethiol (MeSH), another volatile whose reactivity has hitherto hampered measurements. An international team of researchers (Spain, Argentina, China, USA – Old Dominion University, France) compiled a database of seawater MeSH concentrations, identified their statistical predictors, and produced monthly fields of global marine MeSH emissions adding to DMS emissions. Implemented into a global chemistry-climate model, MeSH emissions increased the sulfate aerosol burden by 30 to 70% over the Southern Ocean and enhanced the aerosol cooling effect while depleting atmospheric oxidants and increasing DMS lifetime and transport. According to the researchers accounting for MeSH emissions reduces the radiative bias of current climate models in climatically relevant region…read more. Open Access TECHNICAL ARTICLE
Increase in the annual mean tropospheric burdens of SO2 and SO42− and the radiative effect accounted for by MeSH emissions. Credit: Science Advances, 27 Nov 2024, Vol 10, Issue 48