In:
Biogeosciences, Copernicus GmbH, Vol. 20, No. 4 ( 2023-02-24), p. 851-867
Abstract:
Abstract. Dimethyl sulfide (DMS) plays an important role in the atmosphere by influencing the formation of aerosols and cloud condensation nuclei. In
contrast, the role of methanethiol (MeSH) for the budget and flux of reduced sulfur remains poorly understood. In the present study, we
quantified DMS and MeSH together with the trace gases carbon monoxide (CO), isoprene, acetone, acetaldehyde and acetonitrile in
North Atlantic and Arctic Ocean surface waters, covering a transect from 57.2 to 80.9∘ N in high spatial resolution in May–June
2015. Whereas isoprene, acetone, acetaldehyde and acetonitrile concentrations decreased northwards, CO, DMS and MeSH retained
substantial concentrations at high latitudes, indicating specific sources in polar waters. DMS was the only compound with a higher average concentration in
polar (31.2 ± 9.3 nM) than in Atlantic waters (13.5 ± 2 nM), presumably due to DMS originating from sea ice. At
eight sea-ice stations north of 80∘ N, in the diatom-dominated marginal ice zone, DMS and chlorophyll a markedly correlated
(R2 = 0.93) between 0–50 m depth. In contrast to previous studies, MeSH and DMS did not co-vary, indicating decoupled
processes of production and conversion. The contribution of MeSH to the sulfur budget (represented by DMS + MeSH) was on
average 20 % (and up to 50 %) higher than previously observed in the Atlantic and Pacific oceans, suggesting MeSH as an important
source of sulfur possibly emitted to the atmosphere. The potential importance of MeSH was underlined by several correlations with bacterial
taxa, including typical phytoplankton associates from the Rhodobacteraceae and Flavobacteriaceae families. Furthermore, the
correlation of isoprene and chlorophyll a with Alcanivorax indicated a specific relationship with isoprene-producing
phytoplankton. Overall, the demonstrated latitudinal and vertical patterns contribute to understanding how concentrations of central marine trace
gases are linked with chemical and biological dynamics across oceanic waters.
Type of Medium:
Online Resource
ISSN:
1726-4189
DOI:
10.5194/bg-20-851-2023
DOI:
10.5194/bg-20-851-2023-supplement
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2023
detail.hit.zdb_id:
2158181-2
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