Articles | Volume 22, issue 19
https://doi.org/10.5194/bg-22-5511-2025
© Author(s) 2025. 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-22-5511-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
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10 Oct 2025
Research article | Highlight paper |
| 10 Oct 2025
| 10 Oct 2025
A tracer study for the development of in-water monitoring, reporting, and verification (MRV) of ship-based ocean alkalinity enhancement
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Jennie E. Rheuban
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Zhaohui Aleck Wang
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Daniel C. McCorkle
Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Anna P. M. Michel
Department of Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Lukas Marx
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Chloe L. Dean
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
MIT-WHOI Joint Program in Oceanography, Massachusetts Institute of Technology, Cambridge, MA, USA
Kate Morkeski
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Matthew G. Hayden
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Mary Burkitt-Gray
Department of Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Francis Elder
Department of Applied Ocean Physics and Engineering, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Yiming Guo
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Heather H. Kim
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
Ke Chen
Department of Physical Oceanography, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
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Co-editor-in-chief
This study represents a pioneering step in the development of in situ monitoring, reporting, and verification (MRV) frameworks for ocean alkalinity enhancement (OAE), a leading marine carbon dioxide removal strategy. The authors conducted one of the first open-ocean rhodamine tracer release experiments explicitly designed to simulate alkalinity enhancement, demonstrating a scalable and practical approach for tracking the fate of alkalinity additions in dynamic marine environments. By moving beyond theoretical modeling and implementing real world testing, this work establishes a critical methodological foundation for future field trials and offers a replicable strategy for validating carbon removal through OAE.
This study represents a pioneering step in the development of in situ monitoring, reporting, and...
Short summary
Ocean alkalinity enhancement (OAE) is a carbon removal approach in which alkaline materials are added to the marine environment, increasing the ocean's ability to store carbon dioxide. We conducted an open-water experiment releasing and tracking a fluorescent water tracer. Under the right conditions, in-water monitoring of OAE does appear to be possible. We conclude with a series of practical recommendations for open-water OAE monitoring.
Ocean alkalinity enhancement (OAE) is a carbon removal approach in which alkaline materials are...
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