Earth System Science Data Discussions www.earth-syst-sci-data-discuss.net 1866-3591 3 1 2010 10.5194/essdd-3-1-2010 http://www.earth-syst-sci-data-discuss.net/3/1/2010/ http://www.earth-syst-sci-data-discuss.net/3/1/2010/essdd-3-1-2010.html http://www.earth-syst-sci-data-discuss.net/3/1/2010/essdd-3-1-2010.pdf 1 26 2010-01-11 CARINA TCO₂ data in the Atlantic Ocean D. Pierrot dpierrot@rsmas.miami.edu P. Brown S. Van Heuven T. Tanhua U. Schuster R. Wanninkhof R. M. Key Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School for Marine and Atmospheric Science, Univ. 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 Univ., 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 Water column data of carbon and carbon-relevant hydrographic and hydrochemical parameters from 188 cruises in the Arctic, 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 to assure the highest possible quality and consistency. 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 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, 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° S. Here we report the details of the secondary QC which was done on the total dissolved inorganic carbon (TCO₂) data and the adjustments that were applied to yield the final data product in the Atlantic. 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