Earth System Science Data Discussions www.earth-syst-sci-data-discuss.net 1866-3591 2 1 2009 10.5194/essdd-2-309-2009 http://www.earth-syst-sci-data-discuss.net/2/309/2009/ http://www.earth-syst-sci-data-discuss.net/2/309/2009/essdd-2-309-2009.html http://www.earth-syst-sci-data-discuss.net/2/309/2009/essdd-2-309-2009.pdf 309 330 2009-08-27 Nordic Seas total alkalinity data in CARINA A. Olsen are.olsen@gfi.uib.no Bjerknes Centre for Climate Research, UNIFOB AS, Allegaten 55, 5007 Bergen, Norway Department of Chemistry, University of Gothenburg, 41296, Göteborg, Sweden Water column data of carbon and carbon relevant hydrographic and hydrochemical parameters from 188 previously non-publicly available cruises in the Arctic, Atlantic, and Southern Ocean have been retrieved and merged into a new database: CARINA (CARbon IN the Atlantic). The data have been subject to rigorous quality control (QC) in order to ensure highest possible quality and consistency. The data for most of the parameters included were examined in order to quantify systematic biases in the reported values, i.e. secondary quality control. Significant biases have been corrected for in the data products, i.e. the three merged files with measured, calculated and interpolated values for each of the three CARINA regions; the Arctic Mediterranean Seas (AMS), the Atlantic (ATL) and the Southern Ocean (SO). With the adjustments the CARINA database is consistent both internally as well as with GLODAP (Key et al., 2004) and is suitable for accurate assessments of, for example, oceanic carbon inventories and uptake rates and for model validation. The Arctic Mediterranean Seas includes the Arctic Ocean and the Nordic Seas, and the quality control was carried out separately in these two areas. This contribution presents an account of the quality control of the total alkalinity (ALK) data from the Nordic Seas in CARINA. 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