Overview of the Nordic Seas CARINA data and salinity measurements

Abstract

Abstract. 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 include the Arctic Ocean and the Nordic Seas, and the quality control was carried out separately in these two areas. This contribution provides an overview of the CARINA data from the Nordic Seas and summarises the findings of the QC of the salinity data. One cruise had salinity data that were of questionable quality, and these have been removed from the data product. An evaluation of the consistency of the quality controlled salinity data suggests that they are consistent to at least ±0.005. Data coverage and parameter measuredRepository-Reference:

Nordic Seas nutrients data in CARINA

“…c Labelled NC because of we felt that the data could not be soundly QC'd given the high hydrographic variability of the area where these data were obtained, the Nordic Seas-North Atlantic overflow regions. See Olsen et al (2009) for map of station positions of each individual cruise. Table 1 provides an overview of the data that were included in the secondary quality controls described in this paper, and station positions are shown in Fig.…”

“…3 of Olsen et al (2009) for station positions of each cruise), a highly variable water mass region and outside the core area of the crossover analyses. Given this we have normally chosen to label data from this cruise (as well as from cruise 58JH19920712 which covered the same area) Not Considered (NC).…”

“…The data from 32L919930718 were not included either, because of the special region covered by this cruise (East Greenland Shelf and Shelf edge, see Fig. 3 of Olsen et al (2009) for station positions of each individual cruise.). The data from these cruises have been labelled NC (Not considered) in Table 1.…”

“…The crossover and inversion analysis (Gouretski and Jancke, 2001;Johnson et al, 2001) used to evaluate the consistency of the Nordic Seas nutrients data, was carried out using the version of the cnaX routines (Tanhua et al, 2010c) described by (Olsen et al, 2009). Briefly, the crossover points were found by identifying all station pairs, from different cruises, within 300 km from each other.…”

“…The data from these regions were therefore analysed separately. The data from the Arctic Ocean are described by Jutterström et al (2010) while the other Nordic Seas data are described in Jeansson et al (2010), Falck andOlsen (2009), Olsen et al (2009) and Olsen (2009a, b). The data acquisition and quality control by use of control charts and certified reference materials, for two time series stations, one of which is in the Iceland Sea and included in CARINA-AMS, are described in Olafsson et al (2010).…”