Earth System Science Data Discussions www.earth-syst-sci-data-discuss.net 1866-3591 2 1 2009 10.5194/essdd-2-137-2009 http://www.earth-syst-sci-data-discuss.net/2/137/2009/ http://www.earth-syst-sci-data-discuss.net/2/137/2009/essdd-2-137-2009.html http://www.earth-syst-sci-data-discuss.net/2/137/2009/essdd-2-137-2009.pdf 137 180 2009-08-03 CARINA alkalinity data in the Atlantic Ocean A. Velo avelo@iim.csic.es F. F. Perez P. Brown T. Tanhua U. Schuster R. M. Key Instituto de Investigaciones Marinas, CSIC, Eduardo Cabello, 6, 36208 Vigo, Spain School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK Leibniz-Institut für Meereswissenschaften, Marine Biogeochemie, Kiel, Germany Princeton University, Program in Atmospheric and Oceanic Science, Forrestal Campus/Sayre Hall, Princeton, NJ 08544, USA Data on carbon and carbon-relevant hydrographic and hydrochemical parameters from previously non-publicly available cruise data sets in the Arctic, Atlantic and Southern Ocean have been retrieved and merged to a new database: CARINA (CARbon IN the Atlantic). These data have gone through rigorous quality control (QC) procedures to assure the highest possible quality and consistency. The data for most of the measured parameters in the CARINA data base were objectively examined in order to quantify systematic differences in the reported values, i.e. secondary quality control. Systematic biases found in the data have been corrected in the data products, i.e. three merged data files with measured, calculated and interpolated data for each of the three CARINA regions; Arctic, Atlantic and Southern Ocean. Out of a total of 188 cruise entries in the CARINA database, 98 were conducted in the Atlantic Ocean and of these, 75 cruises report alkalinity values. Here we present details of the secondary QC on alkalinity for the Atlantic Ocean part of CARINA. Procedures of quality control, including crossover analysis between cruises and inversion analysis of all crossover data are briefly described. Adjustments were applied to the alkalinity values for 16 of the cruises in the Atlantic Ocean region. With these adjustments the CARINA database is consistent both internally as well as with GLODAP data, an oceanographic data set based on the World Hydrographic Program in the 1990s. 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