Bromine Monoxide Radical Likely Dominates Dimethylsulfide Oxidation before the Springtime Onset of Arctic Ice Melt

Abstract To understand the atmospheric fate of dimethylsulfide (DMS) during the Arctic spring-to-summer transition, we measured volatile methylated sulfur (VMS) species, including DMS and DMS-derived oxidation products, dimethyl sulfoxide (DMSO), and dimethylsulfone (DMSO2), in the Fram Strait during May and June of 2023. Elevated DMSO contributions to VMS accompany depleted O3, high surface albedo, and air temperatures < 0 °C in air masses influenced by snow-covered sea-ice regions, suggesting that BrO•-initiated oxidation dominated DMS loss prior to the onset of sea-ice melt. In GEOS-Chem simulations, BrO• is the dominant oxidant for DMS, but modeled BrO• concentrations from sea-salt debromination alone are too low to replicate observed O3, DMSO, and DMSO2, suggesting a missing source of reactive bromine from sunlit saline snow. BrO•-initiated oxidation reduces the DMS lifetime and oxidizes DMS through methanesulfinic acid (MSIA) more quickly in the gas phase and in higher yields compared to •OH-initiated oxidation alone. Once melt onset begins and snowpack-driven halogen activation shuts off, •OH oxidation likely dominates Arctic DMS oxidation. Our observations highlight the seasonal variability of halogen oxidation impacting sulfur species in the Arctic marine region, which are likely to change as the sea-ice extent decreases and the melt season in the Arctic lengthens.

Authors

Institutions

Publication Details

Journal
Environmental Science & Technology
Published
2026-10-16
DOI
https://doi.org/10.1021/acs.est.6c06288
Primary Topic
Atmospheric chemistry and aerosols
Type
article
Field-Weighted Citation Impact
0.00

Funders

Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

Bromine Monoxide Radical Likely Dominates Dimethylsulfide Oxidation before the Springtime Onset of Arctic Ice Melt

Nicole A. June, William C. Porter, Megan D. Willis, Michael Tjernström et al.
Environmental Science & Technology
Atmospheric chemistry and aerosols
article

Bromine Monoxide Radical Likely Dominates Dimethylsulfide Oxidation before the Springtime Onset of Arctic Ice Melt

Nicole A. June, William C. Porter, Megan D. Willis, Michael Tjernström, Tucker R. Melles, Jeffrey R. Pierce, Betty Croft, Shantanu H. Jathar, Paul Zieger, Linia Tashmim, Cort L. Zang, Lea Haberstock, Siyuan Wang, Rachel Y.‐W. Chang, Anderson Da Silva
article en

Abstract

Abstract To understand the atmospheric fate of dimethylsulfide (DMS) during the Arctic spring-to-summer transition, we measured volatile methylated sulfur (VMS) species, including DMS and DMS-derived oxidation products, dimethyl sulfoxide (DMSO), and dimethylsulfone (DMSO2), in the Fram Strait during May and June of 2023. Elevated DMSO contributions to VMS accompany depleted O3, high surface albedo, and air temperatures < 0 °C in air masses influenced by snow-covered sea-ice regions, suggesting that BrO•-initiated oxidation dominated DMS loss prior to the onset of sea-ice melt. In GEOS-Chem simulations, BrO• is the dominant oxidant for DMS, but modeled BrO• concentrations from sea-salt debromination alone are too low to replicate observed O3, DMSO, and DMSO2, suggesting a missing source of reactive bromine from sunlit saline snow. BrO•-initiated oxidation reduces the DMS lifetime and oxidizes DMS through methanesulfinic acid (MSIA) more quickly in the gas phase and in higher yields compared to •OH-initiated oxidation alone. Once melt onset begins and snowpack-driven halogen activation shuts off, •OH oxidation likely dominates Arctic DMS oxidation. Our observations highlight the seasonal variability of halogen oxidation impacting sulfur species in the Arctic marine region, which are likely to change as the sea-ice extent decreases and the melt season in the Arctic lengthens.

Environmental Science & Technology
Centre National de la Recherche Scientifique (FR), Dalhousie University (CA), Stockholm University (SE), Université de Versailles Saint-Quentin-en-Yvelines (FR), Sorbonne Université (FR), Bolin Centre for Climate Research (SE), Colorado State University (US)
Polarforskningssekretariatet, Carl Tryggers Stiftelse för Vetenskaplig Forskning, Knut och Alice Wallenbergs Stiftelse, Canada First Research Excellence Fund, Directorate for Geosciences, European Research Council, HORIZON EUROPE Climate, Energy and Mobility
Climate action
Openalex Percentile: Top 20%
Atmospheric chemistry and aerosols
DOISourceOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.