Articles | Volume 23, issue 11
https://doi.org/10.5194/bg-23-3965-2026
© 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-23-3965-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
16 Jun 2026
Research article |
| 16 Jun 2026
| 16 Jun 2026
Surface area and Ω-aragonite oversaturation as controls of the runaway precipitation process in ocean alkalinity enhancement
Niels Suitner
CORRESPONDING AUTHOR
Department of Earth System Sciences, University of Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany
Department of Earth System Sciences, University of Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany
Selene Varliero
Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Milan, Italy
Giulia Faucher
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstrasse 1–3, 24148 Kiel, Germany
Philipp Suessle
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstrasse 1–3, 24148 Kiel, Germany
Charly A. Moras
Department of Earth System Sciences, University of Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany
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Short summary
Alkalinity leakage limits the efficiency of ocean alkalinity enhancement. Drivers of this process remain unquantified, restricting accurate assessments. The induced runaway process can be modeled using surface area and aragonite oversaturation as key factors. This study proposes a framework for improving predictability of alkalinity loss due to runaway precipitation, emphasizing the need for field experiments to validate theoretical models concerning dilution and particle sinking processes.
Alkalinity leakage limits the efficiency of ocean alkalinity enhancement. Drivers of this...
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