An updated synthesis of ocean total alkalinity and dissolved inorganic carbon measurements from 1993 to 2023: the SNAPO-CO <sub>2</sub> -v2 dataset

Abstract. Total alkalinity (AT) and dissolved inorganic carbon (CT) in the oceans are important properties to understand the ocean carbon cycle and its link with global change (ocean carbon sinks and sources, ocean acidification) and ultimately to find carbon-based solutions or mitigation procedures (marine carbon removal). We present an extended database (SNAPO-CO2; Metzl et al., 2024c) with 24 700 new additional data for the period 2002 to 2023. The full database now includes more than 67 000 AT and CT observations along with basic ancillary data (time and space location, depth, temperature, and salinity) in various oceanic regions obtained since 1993 mainly in the framework of French research projects. This includes both surface and water columns data acquired in open oceans, coastal zones, rivers, the Mediterranean Sea, and either from time series stations or punctual cruises. Most AT and CT data in this synthesis were measured from discrete samples using the same closed-cell potentiometric titration calibrated with certified reference material, with an overall accuracy of ±4 µmol kg−1 for both AT and CT. The same technique was used on board for underway measurements during cruises conducted in the southern Indian and Southern oceans. The AT and CT data from these cruises are also added to this synthesis. The data are provided in one dataset for the global ocean (https://doi.org/10.17882/102337, Metzl et al., 2024c) that offers a direct use for regional or global purposes, e.g., AT–salinity relationships, long-term CT estimates, constraint and validation of diagnostics CT and AT reconstructed fields, ocean carbon and coupled climate–carbon models simulations, and data derived from Biogeochemical Argo (BGC-Argo) floats. These data can also be used to calculate pH, fugacity of CO2 (fCO2), and other carbon system properties to derive ocean acidification rates or air–sea CO2 fluxes.

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Publication Details

Journal
Earth system science data
Published
2025-03-14
DOI
https://doi.org/10.5194/essd-17-1075-2025
Citations
5
Primary Topic
Ocean Acidification Effects and Responses
Type
article
Field-Weighted Citation Impact
8.97

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article

An updated synthesis of ocean total alkalinity and dissolved inorganic carbon measurements from 1993 to 2023: the SNAPO-CO 2 -v2 dataset

Jonathan Fin, Sébastien Petton, Steeve Comeau, Emilie Grossteffan et al.
5 citations
Earth system science data
Ocean Acidification Effects and Responses
8.97
article

An updated synthesis of ocean total alkalinity and dissolved inorganic carbon measurements from 1993 to 2023: the SNAPO-CO 2 -v2 dataset

Jonathan Fin, Sébastien Petton, Steeve Comeau, Emilie Grossteffan, Nathalie Lefèvre, Christophe Rabouille, Coraline Leseurre, Gilles Reverdin, Bruno Bombled, Catherine Goyet, Céline Ridame, Claude Mignon, Samir Alliouane, Bruno Lansard, Thibaut Wagener, Pascal Conan, Eva Ferreira, Pascale Cuet, Frédéric Gazeau, Jean‐François Ternon, Nicolas Metzl, Aline Tribollet, Cathy Wimart-Rousseau, Mireille Pujo‐Pay, Yann Bozec, Laurent Coppola, Claire Lo Monaco, Jean‐Pierre Gattuso, Franck Touratier, Dominique Lefèvre, Peggy Rimmelin-Maury, Jacqueline Boutin
article en
5 citations

Abstract

Abstract. Total alkalinity (AT) and dissolved inorganic carbon (CT) in the oceans are important properties to understand the ocean carbon cycle and its link with global change (ocean carbon sinks and sources, ocean acidification) and ultimately to find carbon-based solutions or mitigation procedures (marine carbon removal). We present an extended database (SNAPO-CO2; Metzl et al., 2024c) with 24 700 new additional data for the period 2002 to 2023. The full database now includes more than 67 000 AT and CT observations along with basic ancillary data (time and space location, depth, temperature, and salinity) in various oceanic regions obtained since 1993 mainly in the framework of French research projects. This includes both surface and water columns data acquired in open oceans, coastal zones, rivers, the Mediterranean Sea, and either from time series stations or punctual cruises. Most AT and CT data in this synthesis were measured from discrete samples using the same closed-cell potentiometric titration calibrated with certified reference material, with an overall accuracy of ±4 µmol kg−1 for both AT and CT. The same technique was used on board for underway measurements during cruises conducted in the southern Indian and Southern oceans. The AT and CT data from these cruises are also added to this synthesis. The data are provided in one dataset for the global ocean (https://doi.org/10.17882/102337, Metzl et al., 2024c) that offers a direct use for regional or global purposes, e.g., AT–salinity relationships, long-term CT estimates, constraint and validation of diagnostics CT and AT reconstructed fields, ocean carbon and coupled climate–carbon models simulations, and data derived from Biogeochemical Argo (BGC-Argo) floats. These data can also be used to calculate pH, fugacity of CO2 (fCO2), and other carbon system properties to derive ocean acidification rates or air–sea CO2 fluxes.

Earth system science dataVol. 17(3)
Flanders Marine Institute (BE), Centre National de la Recherche Scientifique (FR), Université de Toulon (FR), Université de Perpignan (FR), Ifremer (FR), Université de Bretagne Occidentale (FR), Université de Versailles Saint-Quentin-en-Yvelines (FR), National Oceanography Centre (GB), Université de Montpellier (FR), Commissariat à l'Énergie Atomique et aux Énergies Alternatives (FR), Station Biologique de Roscoff (FR), Sorbonne Université (FR), Centre d'Économie de la Sorbonne (FR), Labex Corail (FR), Institut des Sciences de la Terre (FR), Adaptation et Diversité en Milieu Marin (FR), Institut du Développement Durable et des Relations Internationales (FR), Laboratoire des Sciences du Climat et de l'Environnement (FR), CEA Paris-Saclay (FR), Marine Biodiversity Exploitation and Conservation (FR), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (FR), Institut Universitaire Européen de la Mer (FR), Laboratoire d’Océanographie de Villefranche (FR), Laboratoire des Sciences de l'Environnement Marin (FR), Laboratoire d'Océanographie Microbienne (FR), Institut de Recherche pour le Développement (FR), Observatoire des sciences de l'Univers Paris-Centre Ecce Terra
Sight Research UK, Natural Environment Research Council, Institut national des sciences de l'Univers
Openalex Percentile: Top 2%
Ocean Acidification Effects and Responses
8.97
DOIOpen Access PDFOpenAlex
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