Earth System Science Data Discussions www.earth-syst-sci-data-discuss.net 1866-3591 2 1 2009 10.5194/essdd-2-103-2009 http://www.earth-syst-sci-data-discuss.net/2/103/2009/ http://www.earth-syst-sci-data-discuss.net/2/103/2009/essdd-2-103-2009.html http://www.earth-syst-sci-data-discuss.net/2/103/2009/essdd-2-103-2009.pdf 103 135 2009-08-03 CARINA-Oxygen: a new high-quality oxygen database for the Atlantic Ocean I. Stendardo N. Gruber A. Körtzinger Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zürich, Switzerland Leibniz Institute for Marine Sciences (IFM-GEOMAR), Chemical Oceanography, Kiel, Germany In the CARINA project, a new dataset with many previously unpublished hydrographic data from the Atlantic, Arctic and Southern Ocean was assembled and subjected to careful quality control (QC) procedures. In this paper, we present the dissolved oxygen measurements in the Atlantic region of the database and describe in detail the secondary QC procedures that aim to ensure optimal consistency between different cruises in order to permit studies of long-term change. The secondary QC is based on a cross-over analysis, i.e. the comparison of deep ocean data at places that were sampled by different cruises at different times. Initial adjustments to the individual cruises were then determined by an inverse procedure that computes a set of adjustments that requires the minimum amount of adjustment and at the same time reduces the offsets in an optimal manner. The initial adjustments were then reviewed by the CARINA members, and only those that passed the following two criteria were adopted: (i) the region not subject to substantial temporal variability, and (ii) the adjustment must be based on at least three stations from each cruise. 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