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Abstract.A compiled set of in situ data is important to evaluate the quality of ocean-colour satellite-data records. Here we describe the data compiled for the validation of the ocean-colour products from the ESA Ocean Colour Climate Change Initiative (OC-CCI). The data were acquired from several sources (MOBY, BOUSSOLE, AERONET-OC, SeaBASS, NOMAD, MERMAID, AMT, ICES, HOT, GeP&CO), span between 1997 and 2012, and have a global distribution. Observations of the following variables were compiled: spectral remote-sensing reflectances, concentrations of chlorophyll a, spectral inherent optical properties and spectral diffuse attenuation coefficients. The data were from multi-project archives acquired via the open internet services or from individual projects, acquired directly from data providers. Methodologies were implemented for homogenisation, quality control and merging of all data. No changes were made to the original data, other than averaging of observations that were close in time and space, elimination of some points after quality control and conversion to a standard format. The final result is a merged table designed for validation of satellite-derived ocean-colour products and available in text format. Metadata of each in situ measurement (original source, cruise or experiment, principal investigator) were preserved throughout the work and made available in the final table. Using all the data in a validation exercise increases the number of matchups and enhances the representativeness of different marine regimes. By making available the metadata, it is also possible to analyse each set of data separately. The compiled data are available at doi:10.1594/PANGAEA.854832 (Valente et al., 2015).

[1] Two bottom-mounted acoustic Doppler current profilers and a vertical string of temperature, conductivity, and pressure sensors were deployed at each end of the Bosphorus Strait in September 2008 and remained in place for over 5 months. These observations showed a two-layer structure of the exchange flow in the Bosphorus Strait with brackish waters originating in the Black Sea moving southward and more saline, denser waters from the Sea of Marmara flowing northward. Considerable differences in mean flow, current fluctuations, and layer thickness were also found. In the northern Bosphorus, the current variations were more pronounced in the lower layer than in the upper layer. The opposite situation was observed in the southern Bosphorus where the upper layer currents fluctuated more noticeably. The near-surface currents often exceeded 200 cm/s in the southern section and were generally below 30 cm/s in the northern section. Currents usually below 70 cm/s were observed in the lower layer in the southern part of the strait, while the lower layer outflow to the Black Sea in the northern part of the strait frequently reached 100 cm/s, with flow concentrated in a strong midlayer maximum core. The upper layer thickness displayed temporal variability and, on average, was about 39 m near its northern end and about 14 m near its southern end. Flow variability was found to be closely associated with variability of the bottom pressure difference and the atmospheric forcing on the synoptic time scale (2-10 days).

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