Articles | Volume 22, issue 3
https://doi.org/10.5194/os-22-1781-2026
© 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/os-22-1781-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
03 Jun 2026
Research article |
| 03 Jun 2026
| 03 Jun 2026
Sea ice melt drives vertical pCO2 variability modulating air–sea gas exchange
Henry C. Henson
CORRESPONDING AUTHOR
Department of Ecoscience, Aarhus University, Aarhus, 8000, Denmark
Arctic Research Center, Aarhus University, Aarhus, 8000, Denmark
Dorte H. Søgaard
Arctic Research Center, Aarhus University, Aarhus, 8000, Denmark
Greenland Climate Research Cluster, Greenland Institute of Natural Resources, Nuuk, 3900, Greenland, Denmark
Department of Biology, Center for Ice-free Arctic Research, Aarhus University, Aarhus, 8000, Denmark
Bjarne Jensen
Department of Environmental science, Aarhus University, Roskilde, 4000, Denmark
Kunuk Lennert
UiT, The Arctic University of Norway, Tromsø, 9037, Norway
Tim Papakyriakou
Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada
Mikael K. Sejr
Department of Ecoscience, Aarhus University, Aarhus, 8000, Denmark
Arctic Research Center, Aarhus University, Aarhus, 8000, Denmark
Jakob Sievers
Department of Environmental science, Aarhus University, Roskilde, 4000, Denmark
Søren Rysgaard
Arctic Research Center, Aarhus University, Aarhus, 8000, Denmark
Department of Biology, Center for Ice-free Arctic Research, Aarhus University, Aarhus, 8000, Denmark
Lise Lotte Sørensen
Arctic Research Center, Aarhus University, Aarhus, 8000, Denmark
Department of Environmental science, Aarhus University, Roskilde, 4000, Denmark
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Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-549, https://doi.org/10.5194/essd-2026-549, 2026
Preprint under review for ESSD
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Earth Syst. Sci. Data, 18, 6357–6409, https://doi.org/10.5194/essd-18-6357-2026, https://doi.org/10.5194/essd-18-6357-2026, 2026
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Jonathan Fipper, Jakob Abermann, Ingo Sasgen, Henrik Skov, Lise Lotte Sørensen, and Wolfgang Schöner
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Short summary
Sea ice melt adds less-saline water to the surface ocean. This creates vertical gradients in salinity, temperature, and partial pressures of carbon dioxide (pCO2). The concentration difference of pCO2 across the air-ocean boundary is used to estimate gas transfer. Thus, the depth that we measure will impact our estimates. Similar patterns were observed in multiple Arctic fjords years apart, suggesting these vertical gradients may be common during the spring melt season.
Sea ice melt adds less-saline water to the surface ocean. This creates vertical gradients in...
