Through the Cracks: Sea Ice Regions as a Source of Volatile Marine Sulfur in the Springtime Arctic
Year: 2026
Type: article
Abstract: Marine volatile methylated sulfur compounds (VMS) including dimethyl sulfide (DMS) and methanethiol (MeSH), are important natural sources of sulfur to the atmosphere and precursors to aerosols and cloud condensation nuclei. However, observations of DMS and MeSH in regions with sea ice remain limited. We present VMS measurements in the Arctic springtime from the ARTofMELT expedition. Hourly averaged DMS and MeSH observations range from below detection limit (<1 ppt v ) to >1500 ppt v , and from below detection limit (<0.5 ppt v ) to >150 ppt v respectively, with the highest concentrations observed during open ocean influence. MeSH made an important contribution to Arctic atmospheric VMS (median MeSH:DMS ratio of 0.12). In regional atmospheric chemistry model simulations using an oceanic DMS climatology and no sea‐to‐air flux from grid cells with sea ice concentration (SIC) > 0, the DMS log 10 mean bias (LMB) is −0.82 with a mean bias (MB) of −101 ppt v ; the MeSH LMB is −0.81 (MB = −3 ppt v ). Scaling the sea‐to‐air flux by ocean fraction improves the atmospheric VMS model‐observation agreement by better representing VMS emissions during ocean influence from sea‐ice regions. Simulations which scale sea‐to‐air flux by ocean fraction and use different oceanic DMS data sets: the Lana climatology, a machine learning model, and a sea‐ice‐ocean‐biogeochemistry model, have a DMS LMB of 0.22, −0.49, and 0.02, respectively. These analyses provide evidence that MeSH is an important fraction of atmospheric VMS and both partial‐sea‐ice and open‐ocean regions are sources of marine sulfur to the atmosphere in the late‐springtime Arctic, both must be considered in atmospheric models.
DOI: 10.1029/2026jd046878
Authors: Nicole A. June, Cort L. Zang, Samuel E. O’Donnell, Ben G. Kopec, Anderson Da Silva, Betty Croft, Rachel Y.‐W. Chang, Linia Tashmim, Antoine Haddon, Shengqian Zhou, William C. Porter, Jeffrey M. Welker, Shantanu H. Jathar, Nadja Steiner, Michael Tjernström, Paul Zieger, Megan D. Willis, Jeffrey R. Pierce
Institutions: Pacific Northwest National Laboratory, Colorado State University, Michigan Technological University, Centre National de la Recherche Scientifique, Université de Versailles Saint-Quentin-en-Yvelines, Sorbonne Université, Laboratoire atmosphères, milieux, observations spatiales, Dalhousie University, University of California, Riverside, University of Victoria, Washington University in St. Louis, University of Alaska Anchorage, University of Oulu, Fisheries and Oceans Canada, Stockholm University, Bolin Centre for Climate Research
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,070
Funders: National Science Foundation, Polarforskningssekretariatet, University of Alaska Anchorage, European Commission, Canada Research Chairs, Oulun Yliopisto, Ocean Frontier Institute, Canada First Research Excellence Fund, University of the Arctic, Alliance de recherche numérique du Canada, HORIZON EUROPE Framework Programme, Natural Sciences and Engineering Research Council of Canada
Awards: G2204931675, Secondary Marine Aerosol precursors and Links to aerosol growth at ice-melT onset in the Arctic (SMALTA), G378677568, RAPID: Fingerprinting new water-carbon interactions in the Arctic: Isotopic measurements through the Northwest Passage and in Baffin Bay, Clouds and climate transitioning to post-fossil aerosol regime, Support for International Ocean Science Activities Through SCOR, Climate relevant interactions and feedbacks: the key role of sea ice and snow in the polar and global climate system, G830695960
OpenAlex ID: W7223088126