Articles | Volume 23, issue 4
https://doi.org/10.5194/bg-23-1653-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-1653-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Spatial variability of greenhouse gas concentrations and fluxes in shallow coastal bays of the western Baltic Sea
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Joakim P. Hansen
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Martijn Hermans
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Alexis Fonseca
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden
Sofia A. Wikström
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Linda Kumblad
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Emil Rydin
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Marc Geibel
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Matthew E. Salter
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Department of Environmental Science, Stockholm University, Stockholm, Sweden
Christoph Humborg
Baltic Sea Centre, Stockholm University, Stockholm, Sweden
Department of Environmental Science, Stockholm University, Stockholm, Sweden
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Robert Wagner, Luisa Ickes, Allan K. Bertram, Nora Els, Elena Gorokhova, Ottmar Möhler, Benjamin J. Murray, Nsikanabasi Silas Umo, and Matthew E. Salter
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Sea spray aerosol particles are a mixture of inorganic salts and organic matter from phytoplankton organisms. At low temperatures in the upper troposphere, both inorganic and organic constituents can induce the formation of ice crystals and thereby impact cloud properties and climate. In this study, we performed experiments in a cloud simulation chamber with particles produced from Arctic seawater samples to quantify the relative contribution of inorganic and organic species in ice formation.
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Short summary
This study presents one of the few studies to simultaneously measure all three major greenhouse gases across multiple shallow coastal bays in the Baltic Sea. Our findings reveal that these bays are highly variable and significant sources of greenhouse gases, with fluxes strongly influenced by bay characteristics and seasonal variation. By linking concentrations to environmental drivers, our work provides novel insights into overlooked but important components of coastal greenhouse gas budgets.
This study presents one of the few studies to simultaneously measure all three major greenhouse...
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