Articles | Volume 22, issue 1
https://doi.org/10.5194/os-22-145-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/os-22-145-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
14 Jan 2026
Research article | Highlight paper |
| 14 Jan 2026
| 14 Jan 2026
Compounded effects of long-term warming and the exceptional 2023 marine heatwave on North Atlantic coccolithophore bloom dynamics
Thibault Guinaldo
CORRESPONDING AUTHOR
Centre National de Recherches Météorologiques, Université de Toulouse, Météo-France, CNRS, Toulouse, France
Griet Neukermans
MarSens Research Group, Faculty of Sciences, Ghent University, 9000 Ghent, Belgium
Flanders Marine Institute, InnovOcean Campus, 8400 Ostend, Belgium
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Co-editor-in-chief
The paper contributes to our knowledge of the impact of marine heat waves on ecosystems, a subject that is topical and that we know little of. The impact on coccolithophores is important for carbon uptake. The impact of MHW more generally on algal blooms is also important for higher trophic levels, the wider ecosystem, and for commercial interests such as aquaculture. The study gives useful confirmation that the environmental ranges defined by O’Brien et al for coccolithophore blooms do seem to apply even in these anomalous MHW conditions and in two separate regions.
The paper contributes to our knowledge of the impact of marine heat waves on ecosystems, a...
Short summary
In 2023, an exceptional marine heatwave occurred in the North Atlantic ocean. This study evaluates changes in G.huxleyi dynamics showing bloom decline in the Celtic Sea and reaching unprecedented levels in the Barents Sea. These shifts reflect the direct impact of temperature extremes driven by human-induced climate change with major effects on ocean life and carbon cycle. Continuous monitoring is vital to understand and monitor regional adaptation of marine ecosystems.
In 2023, an exceptional marine heatwave occurred in the North Atlantic ocean. This study...
