Articles | Volume 21, issue 15
https://doi.org/10.5194/bg-21-3551-2024
© Author(s) 2024. 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-21-3551-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Aug 2024
Research article |
| 09 Aug 2024
| 09 Aug 2024
An assessment of ocean alkalinity enhancement using aqueous hydroxides: kinetics, efficiency, and precipitation thresholds
Mallory C. Ringham
CORRESPONDING AUTHOR
Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY, USA
current address: Ebb Carbon Inc., San Carlos, CA, USA
Nathan Hirtle
Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY, USA
Cody Shaw
Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY, USA
Xi Lu
Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY, USA
Julian Herndon
Cooperative Institute for Climate Ocean and Ecosystem Studies, University of Washington, Seattle, WA, USA
Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, WA, USA
Brendan R. Carter
Cooperative Institute for Climate Ocean and Ecosystem Studies, University of Washington, Seattle, WA, USA
Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, WA, USA
Matthew D. Eisaman
Department of Earth & Planetary Sciences, Yale University, New Haven, CT, USA
Yale Center for Natural Carbon Capture, Yale University, New Haven, CT, USA
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Nico Lange, Siv K. Lauvset, Brendan R. Carter, Matthew P. Humphreys, Ryan J. Woosley, Are Olsen, Henry C. Bittig, Alex Kozyr, Marta Álvarez, Kumiko Azetsu-Scott, Susan Becker, Peter J. Brown, Leticia Cotrim da Cunha, Larissa Dias, Mario Hoppema, Masao Ishii, Emil Jeansson, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Carsten Schirnick, Reiner Steinfeldt, Adam Ulfsbo, Anton Velo, and Toste Tanhua
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-496, https://doi.org/10.5194/essd-2026-496, 2026
Preprint under review for ESSD
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv3 is the third version release of GLODAP. The data that are included have been subjected to extensive quality control, including systematic evaluation of systematic cruise differences. This version contains data from 1181 hydrographic cruises covering the world's oceans from 1972 to 2023.
Hyelim Yoo, Li-Qing Jiang, Chris Langdon, Alex Kozyr, Simone R. Alin, Jose Martin Hernandez Ayon, Kumiko Azetsu-Scott, Leticia Barbero, Nicole Besemer, Albert Boyd, Jean R. Brodeur, Wei-Jun Cai, Brendan R. Carter, Cecilia Chapa, Eugene Colbourne, Jessica N. Cross, Ian Enochs, Leticia Espinosa-Carreon, Richard A. Feely, Karina E. Giesbrecht, Helen Gurney-Smith, Burke Hales, Naomi Harada, James Hooper, Christopher W. Hunt, Debby Ianson, Mike Jankulak, Terrence M. Joyce, Esther G. Kennedy, Brian A. King, Arne Körtzinger, Matthias Lankhorst, Gary Maillet, Derek Manzello, Anna K. McLaskey, Viviane V. Menezes, Nicolas Metzl, Christine Michel, Natalie M. Monacci, Julio M. Morell, Akihiko Murata, Jan Newton, Emily O'Grady, Ana M. Palacio-Castro, Denis Pierrot, Marc Ringuette, Christopher Sabine, Joseph E. Salisbury, Akash R. Sastri, Ute Schuster, Uwe Send, Ryan Smith, Michel Starr, James H. Swift, Lynne D. Talley, Helmuth Thomas, Douglas W. R. Wallace, Zhaohui Aleck Wang, Rik Wanninkhof, Chi S. Wong, Patricia L. Yager, and Igor Yashayaev
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-516, https://doi.org/10.5194/essd-2026-516, 2026
Preprint under review for ESSD
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The coastal Ocean Data Analysis Product in North America (CODAP-NA, Version 2026) substantially increased both the spatial and temporal coverage of coastal biogeochemical measurements across North American continental shelves. This version comprises 446 cruises, 31,864 hydrographic profiles, and 195,489 discrete data records covering continental shelf environments from Alaska to Mexico in the west and from Canada to the Caribbean in the east from 1981 to 2024.
Daniel E. Sandborn, Brendan R. Carter, Mark J. Warner, and Larissa M. Dias
Geosci. Model Dev., 19, 5961–5978, https://doi.org/10.5194/gmd-19-5961-2026, https://doi.org/10.5194/gmd-19-5961-2026, 2026
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We present a new implementation of our method for estimation of human-created carbon dioxide in the ocean.
Tracer-based Rapid Anthropogenic Carbon Estimationrelies on transient tracer measurements to infer gas exchange and circulation. Our work implements practical and fundamental improvements increasing accessibility, flexibility, and skill of the method. We provide an updated data product of global ocean carbon inventories spanning the industrial era and a range of future projections.
Matthew P. Humphreys, Siv K. Lauvset, Nico Lange, Henry C. Bittig, Brendan R. Carter, Mario Hoppema, Akihiko Murata, Are Olsen, Toste Tanhua, Adam Ulfsbo, Antón Velo, Ryan J. Woosley, Kumiko Azetsu-Scott, Jens D. Müller, and Fiz F. Pérez
EGUsphere, https://doi.org/10.5194/egusphere-2026-3063, https://doi.org/10.5194/egusphere-2026-3063, 2026
This preprint is open for discussion and under review for Ocean Science (OS).
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The Global Ocean Data Analysis Project (GLODAP) collects oceanographic datasets from research cruises that are needed to study the marine carbon cycle. The datasets are quality controlled and adjusted where necessary to ensure consistency between cruises, and published as a global data product. Here, we present a new method for calculating the consistency adjustments called ‘furthest-first inversion’ which has been developed for the newest version of the data product.
Li-Qing Jiang, Amanda Fay, Jens Daniel Müller, Luke Gregor, Alizée Roobaert, Lydia Keppler, Dustin Carroll, Siv K. Lauvset, Tim DeVries, Judith Hauck, Christian Rödenbeck, Nicolas Metzl, Andrea J. Fassbender, Jean-Pierre Gattuso, Peter Landschützer, Rik Wanninkhof, Christopher Sabine, Simone R. Alin, Mario Hoppema, Are Olsen, Matthew P. Humphreys, Kunal Chakraborty, Ana C. Franco, Kumiko Azetsu-Scott, Dorothee C. E. Bakker, Leticia Barbero, Nicholas R. Bates, Nicole Besemer, Henry C. Bittig, Albert E. Boyd, Daniel Broullón, Wei-Jun Cai, Brendan R. Carter, Thi-Tuyet-Trang Chau, Chen-Tung Arthur Chen, Frédéric Cyr, John E. Dore, Ian Enochs, Richard A. Feely, Hernan E. Garcia, Marion Gehlen, Prasanna Kanti Ghoshal, Lucas Gloege, Melchor González-Dávila, Nicolas Gruber, Debby Ianson, Yosuke Iida, Masao Ishii, Apurva Padamnabh Joshi, Esther Kennedy, Alex Kozyr, Nico Lange, Claire Lo Monaco, Derek P. Manzello, Galen A. McKinley, Natalie M. Monacci, Xose A. Padin, Ana M. Palacio-Castro, Fiz F. Pérez, J. Magdalena Santana-Casiano, Jonathan Sharp, Adrienne Sutton, Jim Swift, Toste Tanhua, Maciej Telszewski, Jens Terhaar, Ruben van Hooidonk, Anton Velo, Andrew J. Watson, Angelicque E. White, Zelun Wu, Liang Xue, Hyelim Yoo, Jiye Zeng, and Guorong Zhong
Earth Syst. Sci. Data, 18, 1405–1462, https://doi.org/10.5194/essd-18-1405-2026, https://doi.org/10.5194/essd-18-1405-2026, 2026
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This review article provides an overview of 68 existing ocean carbonate chemistry data products and data product sets, encompassing a broad range of types, including compilations of cruise datasets, gap-filled observational products, model simulations, and more. It is designed to help researchers identify and access the data products that best support their scientific objectives, thereby facilitating progress in understanding the ocean's changing carbonate chemistry.
Larissa M. Dias and Brendan R. Carter
Geosci. Model Dev., 18, 7275–7295, https://doi.org/10.5194/gmd-18-7275-2025, https://doi.org/10.5194/gmd-18-7275-2025, 2025
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The increasing availability of oceanographic physical and chemical data necessitates accompanying methods for optimizing use of these data. This project produced algorithms (PyESPERs) for estimating biogeochemical seawater properties in Python, a freely available coding language. These algorithms were based on empirical seawater property estimation routines (ESPERs), which were originally written in the proprietary MATLAB coding language and can be used in studies of marine carbonate chemistry.
Brendan R. Carter, Jörg Schwinger, Rolf Sonnerup, Andrea J. Fassbender, Jonathan D. Sharp, Larissa M. Dias, and Daniel E. Sandborn
Earth Syst. Sci. Data, 17, 3073–3088, https://doi.org/10.5194/essd-17-3073-2025, https://doi.org/10.5194/essd-17-3073-2025, 2025
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We infer ocean gas exchange and circulation from ocean tracer measurements and use this to create code to estimate the amount of carbon dioxide dissolved in the ocean that is there due to human emissions of CO2 into the atmosphere. The code works across the ocean depths for the past, present, or future from information about the location, temperature, and salinity of the seawater. We produce a data product with estimates throughout the ocean throughout the last ~300 and the next ~500 years.
Kristin Jones, Lenaïg G. Hemery, Nicholas D. Ward, Peter J. Regier, Mallory C. Ringham, and Matthew D. Eisaman
Biogeosciences, 22, 1615–1630, https://doi.org/10.5194/bg-22-1615-2025, https://doi.org/10.5194/bg-22-1615-2025, 2025
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Ocean alkalinity enhancement is a marine carbon dioxide removal method that aims to mitigate the effects of climate change. This method causes localized increases in ocean pH, but the biological impacts of such changes are not well known. Our study investigated the response of two nearshore invertebrate species to increased pH and found the sea hare to be sensitive to pH changes, whereas the isopod was more resilient. Understanding interactions with biology is important as this field expands.
Li-Qing Jiang, Tim P. Boyer, Christopher R. Paver, Hyelim Yoo, James R. Reagan, Simone R. Alin, Leticia Barbero, Brendan R. Carter, Richard A. Feely, and Rik Wanninkhof
Earth Syst. Sci. Data, 16, 3383–3390, https://doi.org/10.5194/essd-16-3383-2024, https://doi.org/10.5194/essd-16-3383-2024, 2024
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In this paper, we unveil a data product featuring ten coastal ocean acidification variables. These indicators are provided on 1°×1° spatial grids at 14 standardized depth levels, ranging from the surface to a depth of 500 m, along the North American ocean margins.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Marta Álvarez, Kumiko Azetsu-Scott, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 16, 2047–2072, https://doi.org/10.5194/essd-16-2047-2024, https://doi.org/10.5194/essd-16-2047-2024, 2024
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2023 is the fifth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1108 hydrographic cruises covering the world's oceans from 1972 to 2021.
Simone R. Alin, Jan A. Newton, Richard A. Feely, Dana Greeley, Beth Curry, Julian Herndon, and Mark Warner
Earth Syst. Sci. Data, 16, 837–865, https://doi.org/10.5194/essd-16-837-2024, https://doi.org/10.5194/essd-16-837-2024, 2024
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The Salish cruise data product provides 2008–2018 oceanographic data from the southern Salish Sea and nearby coastal sampling stations. Temperature, salinity, oxygen, nutrient, and dissolved inorganic carbon measurements from 715 oceanographic profiles will facilitate further study of ocean acidification, hypoxia, and marine heatwave impacts in this region. Three subsets of the compiled datasets from 35 cruises are available with consistent formatting and multiple commonly used units.
Katja Fennel, Matthew C. Long, Christopher Algar, Brendan Carter, David Keller, Arnaud Laurent, Jann Paul Mattern, Ruth Musgrave, Andreas Oschlies, Josiane Ostiguy, Jaime B. Palter, and Daniel B. Whitt
State Planet, 2-oae2023, 9, https://doi.org/10.5194/sp-2-oae2023-9-2023, https://doi.org/10.5194/sp-2-oae2023-9-2023, 2023
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This paper describes biogeochemical models and modelling techniques for applications related to ocean alkalinity enhancement (OAE) research. Many of the most pressing OAE-related research questions cannot be addressed by observation alone but will require a combination of skilful models and observations. We present illustrative examples with references to further information; describe limitations, caveats, and future research needs; and provide practical recommendations.
Matthew D. Eisaman, Sonja Geilert, Phil Renforth, Laura Bastianini, James Campbell, Andrew W. Dale, Spyros Foteinis, Patricia Grasse, Olivia Hawrot, Carolin R. Löscher, Greg H. Rau, and Jakob Rønning
State Planet, 2-oae2023, 3, https://doi.org/10.5194/sp-2-oae2023-3-2023, https://doi.org/10.5194/sp-2-oae2023-3-2023, 2023
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Ocean-alkalinity-enhancement technologies refer to various methods and approaches aimed at increasing the alkalinity of seawater. This chapter explores technologies for increasing ocean alkalinity, including electrochemical-based approaches, ocean liming, accelerated weathering of limestone, hydrated carbonate addition, and coastal enhanced weathering, and suggests best practices in research and development.
Jonathan D. Sharp, Andrea J. Fassbender, Brendan R. Carter, Gregory C. Johnson, Cristina Schultz, and John P. Dunne
Earth Syst. Sci. Data, 15, 4481–4518, https://doi.org/10.5194/essd-15-4481-2023, https://doi.org/10.5194/essd-15-4481-2023, 2023
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Dissolved oxygen content is a critical metric of ocean health. Recently, expanding fleets of autonomous platforms that measure oxygen in the ocean have produced a wealth of new data. We leverage machine learning to take advantage of this growing global dataset, producing a gridded data product of ocean interior dissolved oxygen at monthly resolution over nearly 2 decades. This work provides novel information for investigations of spatial, seasonal, and interannual variability in ocean oxygen.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Simone Alin, Marta Álvarez, Kumiko Azetsu-Scott, Leticia Barbero, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Mario Hoppema, Matthew P. Humphreys, Masao Ishii, Emil Jeansson, Li-Qing Jiang, Steve D. Jones, Claire Lo Monaco, Akihiko Murata, Jens Daniel Müller, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Adam Ulfsbo, Anton Velo, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 14, 5543–5572, https://doi.org/10.5194/essd-14-5543-2022, https://doi.org/10.5194/essd-14-5543-2022, 2022
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2022 is the fourth update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality controlling, including systematic evaluation of measurement biases. This version contains data from 1085 hydrographic cruises covering the world's oceans from 1972 to 2021.
Jonathan D. Sharp, Andrea J. Fassbender, Brendan R. Carter, Paige D. Lavin, and Adrienne J. Sutton
Earth Syst. Sci. Data, 14, 2081–2108, https://doi.org/10.5194/essd-14-2081-2022, https://doi.org/10.5194/essd-14-2081-2022, 2022
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Oceanographers calculate the exchange of carbon between the ocean and atmosphere by comparing partial pressures of carbon dioxide (pCO2). Because seawater pCO2 is not measured everywhere at all times, interpolation schemes are required to fill observational gaps. We describe a monthly gap-filled dataset of pCO2 in the northeast Pacific Ocean off the west coast of North America created by machine-learning interpolation. This dataset is unique in its robust representation of coastal seasonality.
Siv K. Lauvset, Nico Lange, Toste Tanhua, Henry C. Bittig, Are Olsen, Alex Kozyr, Marta Álvarez, Susan Becker, Peter J. Brown, Brendan R. Carter, Leticia Cotrim da Cunha, Richard A. Feely, Steven van Heuven, Mario Hoppema, Masao Ishii, Emil Jeansson, Sara Jutterström, Steve D. Jones, Maren K. Karlsen, Claire Lo Monaco, Patrick Michaelis, Akihiko Murata, Fiz F. Pérez, Benjamin Pfeil, Carsten Schirnick, Reiner Steinfeldt, Toru Suzuki, Bronte Tilbrook, Anton Velo, Rik Wanninkhof, Ryan J. Woosley, and Robert M. Key
Earth Syst. Sci. Data, 13, 5565–5589, https://doi.org/10.5194/essd-13-5565-2021, https://doi.org/10.5194/essd-13-5565-2021, 2021
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GLODAP is a data product for ocean inorganic carbon and related biogeochemical variables measured by the chemical analysis of water bottle samples from scientific cruises. GLODAPv2.2021 is the third update of GLODAPv2 from 2016. The data that are included have been subjected to extensive quality control, including systematic evaluation of measurement biases. This version contains data from 989 hydrographic cruises covering the world's oceans from 1972 to 2020.
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Short summary
Ocean alkalinity enhancement leverages the large surface area and carbon storage capacity of the oceans to store atmospheric CO2 as dissolved bicarbonate. We monitored CO2 uptake in seawater treated with NaOH to establish operational boundaries for carbon removal experiments. Results show that CO2 equilibration occurred on the order of weeks to months, was consistent with values expected from equilibration calculations, and was limited by mineral precipitation at high pH and CaCO3 saturation.
Ocean alkalinity enhancement leverages the large surface area and carbon storage capacity of the...
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