Marine Emissions of Methanethiol Increase Aerosol Cooling in the Southern Ocean

ORCID

0000-0001-6694-7334 (Williams)

Document Type

Abstract

Publication Date

2025

DOI

10.5194/egusphere-egu25-17784

Publication Title

EGU General Assembly 2025

Pages

1 pp.

Conference Name

EGU General Assembly 2025, April 27-May 2, 2025, Vienna, Austria

Abstract

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. Therefore, the global emissions and climate impact of MeSH remain unexplored. We 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 increase the sulfate aerosol burden by 30 to 70% over the Southern Ocean and enhance the aerosol cooling effect while depleting atmospheric oxidants and increasing DMS lifetime and transport. Accounting for MeSH emissions reduces the radiative bias of current climate models in this climatically relevant region.

Rights

© Authors 2025

This work is distributed under the Creative Commons Attribution 4.0 International (CC BY 4.0) License.

Original Publication Citation

Villamayor, J., Wohl, C., Galí, M., Mahajan, A. S., Fernández, R. P., Cuevas, C. A., Bossolasco, A., Li, Q., Kettle, A. J., Williams, T., Sarda-Esteve, R., Gros, V., Simó, R., and Saiz-Lopez, A.: Marine emissions of methanethiol increase aerosol cooling in the Southern Ocean, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17784, https://doi.org/10.5194/egusphere-egu25-17784, 2025.

Link to Full Text

Share

Article Location

 
COinS