ESSD Earth System Science Data ESSD Earth Syst. Sci. Data 1866-3516 Copernicus Publications Göttingen, Germany 10.5194/essd-2-177-2010 CARINA TCO<sub>2</sub> data in the Atlantic Ocean Pierrot D. 1 Brown P. 2 Van Heuven S. 3 Tanhua T. 4 Schuster U. 2 Wanninkhof R. 5 Key R. M. 6 Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School for Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK Department of Ocean Ecosystems, Faculty of Mathematics and Natural Sciences, University of Groningen, Groningen, The Netherlands Leibniz Institute of Marine Sciences at Kiel University, Duesternbrooker Weg 20, 24105 Kiel, Germany Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, 4301 Rickenbacker Causeway, Miami, FL 33149, USA Princeton University, Program in Atmospheric and Oceanic Science, Forrestal Campus/Sayre Hall, Princeton, NJ 08544, USA 12 07 2010 2 2 177 187 Copyright: © 2010 D. Pierrot et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://essd.copernicus.org/articles/2/177/2010/essd-2-177-2010.html The full text article is available as a PDF file from https://essd.copernicus.org/articles/2/177/2010/essd-2-177-2010.pdf

Water column data of carbon and carbon-relevant hydrographic and hydrochemical parameters from 188 cruises in the Arctic Mediterranean Seas, Atlantic and Southern Ocean have been retrieved and merged in a new data base: the CARINA (CARbon IN the Atlantic) Project. These data have gone through rigorous quality control (QC) procedures so as to improve the quality and consistency of the data as much as possible. Secondary quality control, which involved objective study of data in order to quantify systematic differences in the reported values, was performed for the pertinent parameters in the CARINA data base. Systematic biases in the data have been tentatively corrected in the data products. The products are three merged data files with measured, adjusted and interpolated data of all cruises for each of the three CARINA regions (Arctic Mediterranean Seas, Atlantic and Southern Ocean). Ninety-eight cruises were conducted in the "Atlantic" defined as the region south of the Greenland-Iceland-Scotland Ridge and north of about 30&deg; S. Here we report the details of the secondary QC which was done on the total dissolved inorganic carbon (TCO<sub>2</sub>) data and the adjustments that were applied to yield the final data product in the Atlantic. Procedures of quality control &ndash; including crossover analysis between stations and inversion analysis of all crossover data &ndash; are briefly described. Adjustments were applied to TCO<sub>2</sub> measurements for 17 of the cruises in the Atlantic Ocean region. With these adjustments, the CARINA data base is consistent both internally as well as with GLODAP data, an oceanographic data set based on the WOCE Hydrographic Program in the 1990s, and is now suitable for accurate assessments of, for example, regional oceanic carbon inventories, uptake rates and model validation.

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