Articles | Volume 23, issue 12
https://doi.org/10.5194/bg-23-4321-2026
© 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-23-4321-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
30 Jun 2026
Research article |
| 30 Jun 2026
| 30 Jun 2026
Prediction of present and future spatial occurrence of cyanobacteria and the toxin nodularin in the Baltic Sea
Mohanad Abdelgadir
CORRESPONDING AUTHOR
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, P.O. Box 7050, 750 07, Uppsala, Sweden
Department of Ecology, Environment and Geoscience, Umeå University, 901 87, Umeå, Sweden
Bengt Karlson
Department of Research and Development, Oceanography, Swedish Meteorological and Hydrological Institute, SMHI, 426 71 Västra Frölunda, Sweden
Elin Dahlgren
Department of Aquatic Resources, Swedish University of Agricultural Sciences, Stångholmsvägen 2, 178 93 Drottningholm, Sweden
Malin Olofsson
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, P.O. Box 7050, 750 07, Uppsala, Sweden
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Matteo Masini, Agnes Karlsson, Lars Arneborg, Bengt Karlson, and Inga Monika Koszalka
EGUsphere, https://doi.org/10.5194/egusphere-2026-1344, https://doi.org/10.5194/egusphere-2026-1344, 2026
Short summary
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On the 8th of August, Storm Hans swept through the Baltic Sea disturbing the operation of desalination plants producing drinking water from sea water. In this paper, we build upon reports from the desalination plants to analyze the operational ocean model outputs and observations to identify the coastal processes behind the reported hazards. The results show a potential for future development of forecast framework.
Jenny Hieronymus, Kari Eilola, Malin Olofsson, Inga Hense, H. E. Markus Meier, and Elin Almroth-Rosell
Biogeosciences, 18, 6213–6227, https://doi.org/10.5194/bg-18-6213-2021, https://doi.org/10.5194/bg-18-6213-2021, 2021
Short summary
Short summary
Dense blooms of cyanobacteria occur every summer in the Baltic Proper and can add to eutrophication by their ability to turn nitrogen gas into dissolved inorganic nitrogen. Being able to correctly estimate the size of this nitrogen fixation is important for management purposes. In this work, we find that the life cycle of cyanobacteria plays an important role in capturing the seasonality of the blooms as well as the size of nitrogen fixation in our ocean model.
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Short summary
The study integrated empirical Bayesian kriging, ensemble learning, and stacked species distribution modeling to study the distribution of cyanotoxin nodularin and toxin producer Nodularia spumigena. Area distribution of nodularin is determined by salinity, temperature, phosphate, nitrate-to-phosphate ratio, and distance from shore. Predictions show increased nodularin occurrences in the Eastern Gotland Sea, Northern Baltic Proper, southern parts of the Bothnian Sea, and Arkona Basin by 2100.
The study integrated empirical Bayesian kriging, ensemble learning, and stacked species...
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