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A multi-decade record of high-quality fCO2 data in version 3 of the Surface Ocean CO2 Atlas (SOCAT)

Dorothee Bakker·Camilla S. Landa·Benjamin Pfeil·Nicolas Metzl·Kevin O’Brien·Are Olsen·Karl Smith·Cathy Cosca·Sumiko Harasawa·Shin-ichiro Nakaoka·Stephen Jones·Yukihiro Nojiri·Tobias Steinhoff·Colm Sweeney·Ute Schuster·Taro Takahashi·Bronte Tilbrook·Chisato Wada·Rik Wanninkhof·Simone R. Alin·Carlos F. Balestrini·Leticia Barbero·Nicholas Bates·Alejandro A. Bianchi·Frederic Bonou·Jacqueline Boutin·Yann Bozec·Eugene F. Burger·Wei-Jun Cai·Robert D. Castle·Liqi Chen·Melissa Chierici·Kim Currie·Wiley Evans·Charles Featherstone·Richard Feely·Agneta Fransson·Catherine Goyet·Naomi Greenwood·Luke Gregor·Steven C. Hankin·Nick J. Hardman-Mountford·Jerome Harlay·Judith Hauck·Mario Hoppema·Matthew P. Humphreys·Christopher W. Hunt·Betty Huss·J. Severino P. Ibanhez·Truls Johannessen·Ralph F. Keeling·Vassilis Kitidis·Arne Kortzinger·Alex Kozyr·Evangelia Krasakopoulou·Akira Kuwata·Peter Landschutzer·Siv K. Lauvset·Nathalie Lefevre·Claire Lo Monaco·Ansley Manke·Jeremy T. Mathis·Liliane Merlivat·Frank J. Millero·Pedro M. S. Monteiro·David R. Munro·Akihiko Murata·Timothy Newberger·Abdirahman M. Omar·Tsuneo Ono·Kristina Paterson·David Pearce·Denis Pierrot·Lisa L. Robbins·Shu Saito·Joe Salisbury·Reiner Schlitzer·Bernd Schneider·Roland Schweitzer·Rainer Sieger·Ingunn Skjelvan·Kevin F. Sullivan·Stewart C. Sutherland·Adrienne J. Sutton·Kazuaki Tadokoro·Maciej Telszewski·Matthias Tuma·Steven M. A. C. van Heuven·Douglas Vandemark·Brian Ward·Andrew J. Watson·Suqing Xu
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Abstract

The Surface Ocean CO 2 Atlas (SOCAT) is a synthesis of quality-controlled f CO 2 (fugacity of carbon dioxide) values for the global surface oceans and coastal seas with regular updates. Version 3 of SOCAT has 14.7 million f CO 2 values from 3646 data sets covering the years 1957 to 2014. This latest version has an additional 4.6 million f CO 2 values relative to version 2 and extends the record from 2011 to 2014. Version 3 also significantly increases the data availability for 2005 to 2013. SOCAT has an average of approximately 1.2 million surface water f CO 2 values per year for the years 2006 to 2012. Quality and documentation of the data has improved. A new feature is the data set quality control (QC) flag of E for data from alternative sensors and platforms. The accuracy of surface water f CO 2 has been defined for all data set QC flags. Automated range checking has been carried out for all data sets during their upload into SOCAT. The upgrade of the interactive Data Set Viewer (previously known as the Cruise Data Viewer) allows better interrogation of the SOCAT data collection and rapid creation of high-quality figures for scientific presentations. Automated data upload has been launched for version 4 and will enable more frequent SOCAT releases in the future. High-profile scientific applications of SOCAT include quantification of the ocean sink for atmospheric carbon dioxide and its long-term variation, detection of ocean acidification, as well as evaluation of coupled-climate and ocean-only biogeochemical models. Users of SOCAT data products are urged to acknowledge the contribution of data providers, as stated in the SOCAT Fair Data Use Statement. This ESSD (Earth System Science Data) “living data” publication documents the methods and data sets used for the assembly of this new version of the SOCAT data collection and compares these with those used for earlier versions of the data collection (Pfeil et al., 2013; Sabine et al., 2013; Bakker et al., 2014).

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Dorothee Bakker, Camilla S. Landa, Benjamin Pfeil, Nicolas Metzl, Kevin O’Brien, Are Olsen, Karl Smith, Cathy Cosca, Sumiko Harasawa, Shin-ichiro Nakaoka, Stephen Jones, Yukihiro Nojiri, Tobias Steinhoff, Colm Sweeney, Ute Schuster, Taro Takahashi, Bronte Tilbrook, Chisato Wada, Rik Wanninkhof, Simone R. Alin, Carlos F. Balestrini, Leticia Barbero, Nicholas Bates, Alejandro A. Bianchi, Frederic Bonou, Jacqueline Boutin, Yann Bozec, Eugene F. Burger, Wei-Jun Cai, Robert D. Castle, Liqi Chen, Melissa Chierici, Kim Currie, Wiley Evans, Charles Featherstone, Richard Feely, Agneta Fransson, Catherine Goyet, Naomi Greenwood, Luke Gregor, Steven C. Hankin, Nick J. Hardman-Mountford, Jerome Harlay, Judith Hauck, Mario Hoppema, Matthew P. Humphreys, Christopher W. Hunt, Betty Huss, J. Severino P. Ibanhez, Truls Johannessen, Ralph F. Keeling, Vassilis Kitidis, Arne Kortzinger, Alex Kozyr, Evangelia Krasakopoulou, Akira Kuwata, Peter Landschutzer, Siv K. Lauvset, Nathalie Lefevre, Claire Lo Monaco, Ansley Manke, Jeremy T. Mathis, Liliane Merlivat, Frank J. Millero, Pedro M. S. Monteiro, David R. Munro, Akihiko Murata, Timothy Newberger, Abdirahman M. Omar, Tsuneo Ono, Kristina Paterson, David Pearce, Denis Pierrot, Lisa L. Robbins, Shu Saito, Joe Salisbury, Reiner Schlitzer, Bernd Schneider, Roland Schweitzer, Rainer Sieger, Ingunn Skjelvan, Kevin F. Sullivan, Stewart C. Sutherland, Adrienne J. Sutton, Kazuaki Tadokoro, Maciej Telszewski, Matthias Tuma, Steven M. A. C. van Heuven, Douglas Vandemark, Brian Ward, Andrew J. Watson, Suqing Xu. 2016. A multi-decade record of high-quality fCO2 data in version 3 of the Surface Ocean CO2 Atlas (SOCAT). https://doi.org/10.5194/essd-2016-15

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