The data recorded by the oceanographic platforms operate in the Aegean and the Ionian Seas (fixed stations, ferry box system, gliders) are released through the POSEIDON portal. Physical and biochemical parameters of the marine environment as well as atmospheric parameters in the fixed station locations are available both in real time and delayed mode. The forecasting module of the POSEIDON system consists of four numerical models that provide in daily basis forecasts regarding the atmospheric, sea state, hydrodynamic and ecological conditions of the Eastern Mediterranean. The online POSEIDON database contains the data recorded by the insitu platforms offering also downloading functions for the whole data set, while a user-friendly tool is also available for accessing the results of all the forecasting models for the last five years.

Data access will be provided in near real time and in delayed mode. Parameters include salinity, temperature, chlorophyll fluorescence, turbidity, oxygen, pH, pCO2, wave height and direction, current speed and direction and also in air data on temperature, irradiation and air pressure. Also data from laboratory analyses of water samples are included, e.g. chlorophyll, salinity, CDOM, coloured dissolved organic matter, phytoplankton abundance and biodiversity. Data is distributed through the Baltic Operational Oceanographic System, BOOS and through the Swedish Oceanographic Data Centre at SMHI. Data is accessible through download and through web services. Data and metadata is delivered through SMHI systems for distributing oceanographic data, e.g. http://sharkdata.smhi.se according to EU standards and procedures.

The oceanographic data from the Oslofjord at 1 m and 60 m are in the range of a salinity of ~10-34 and a temperature range of -1 to 20 °C. Other sensor data that can be available are Chl-a fluorescence, turbidity, pH and pCO2. The station will give access to the above data for doing research on biogeochemistry and climate. NIVA staff will support via data QC and setup of remote data access.

Moving 10-years analysis of pH at Mediterranean Sea for each season : - winter (January-March), - spring (April-June), - summer (July-September), - autumn (October-December). Every year of the time dimension corresponds to the 10-year centered average of each season. Decades span from 1959-1968 until 2005-2014. Observational data span from 1930 to 2014. Depth range (IODE standard depths): -1500.0, -1400.0, -1300.0, -1200.0, -1100.0, -1000.0, -900.0, -800.0, -700.0, -600.0, -500.0, -400.0, -300.0, -250.0, -200.0, -150.0, -125.0, -100.0, -75.0, -50.0, -30.0, -20.0, -10.0, -5.0, -0.0. Data Sources: observational data from SeaDataNet/EMODNet Chemistry Data Network. Description of DIVA analysis: Geostatistical data analysis by DIVA (Data-Interpolating Variational Analysis) tool. Profiles were interpolated at standard depths using weighted parabolic interpolation algorithm (Reiniger and Ross, 1968). GEBCO 1min topography is used for the contouring preparation. Analyzed filed masked using relative error threshold 0.3 and 0.5. DIVA settings: A constant value for signal-to-noise ratio was used equal to 1. Correlation length was optimized and filtered vertically and a seasonally-averaged profile was used. Logarithmic transformation applied to the data prior to the analysis. Background field: the data mean value is subtracted from the data. Detrending of data: no. Advection constraint applied: no. Originators of Italian data sets-List of contributors: o Brunetti Fabio (OGS) o Cardin Vanessa, Bensi Manuel doi:10.6092/36728450-4296-4e6a-967d-d5b6da55f306 o Cardin Vanessa, Bensi Manuel, Ursella Laura, Siena Giuseppe doi:10.6092/f8e6d18e-f877-4aa5-a983-a03b06ccb987 o Cataletto Bruno (OGS) o Cinzia Comici Cinzia (OGS) o Civitarese Giuseppe (OGS) o DeVittor Cinzia (OGS) o Giani Michele (OGS) o Kovacevic Vedrana (OGS) o Mosetti Renzo (OGS) o Solidoro C.,Beran A.,Cataletto B.,Celussi M.,Cibic T.,Comici C.,Del Negro P.,De Vittor C.,Minocci M.,Monti M.,Fabbro C.,Falconi C.,Franzo A.,Libralato S.,Lipizer M.,Negussanti J.S.,Russel H.,Valli G., doi:10.6092/e5518899-b914-43b0-8139-023718aa63f5 o Celio Massimo (ARPA FVG) o Malaguti Antonella (ENEA) o Fonda Umani Serena (UNITS) o Bignami Francesco (ISAC/CNR) o Boldrini Alfredo (ISMAR/CNR) o Marini Mauro (ISMAR/CNR) o Miserocchi Stefano (ISMAR/CNR) o Zaccone Renata (IAMC/CNR) o Lavezza, R., Dubroca, L. F. C., Ludicone, D., Kress, N., Herut, B., Civitarese, G., Cruzado, A., Lefèvre, D., Souvermezoglou, E., Yilmaz, A., Tugrul, S., and Ribera d'Alcala, M.: Compilation of quality controlled nutrient profiles from the Mediterranean Sea, doi:10.1594/PANGAEA.771907, 2011. Units: pH units

POSEIDON is an operational marine monitoring, forecasting and information system for the Greek Seas. The observing component is a distributed infrastructure made by three coastal buoys (Saronikos buoy-SB, Heraklion Coastal Buoy-HCB and Athos buoy-AB) and one Ferrybox (PFB). A calibration laboratory) is supporting the observing activities. The Ferrybox is installed on board H/S/F “Knossos Palace” and is equipped with sensors measuring T, C/S, DO, pH, fluorescence and turbidity. It is the only Ferry Box in the Mediterranean operating daily along the route Heraklion – Piraeus.

EMODnet Chemistry aims to provide access to marine chemistry data sets and derived data products concerning eutrophication, ocean acidification and contaminants. The chemicals chosen reflect importance to the Marine Strategy Framework Directive (MSFD). This regional aggregated dataset contains all unrestricted EMODnet Chemistry data on contaminants (20 parameters), and covers the North East Atlantic Ocean with 2400 CDI records divided per matrices: 122 in biota (as time series), 1689 in water (as vertical profiles), 589 in sediment (478 Vertical profiles and 111 Time series). Vertical profiles temporal range is from 1970-07-29 to 2017-02-28. Time series temporal range is from 1979-02-28 to 2014-10-21. Data were aggregated and quality controlled by ‘IFREMER / IDM / SISMER - Scientific Information Systems for the SEA’ from France. Regional datasets concerning contaminants are automatically harvested. Parameter names in these datasets are based on P01, BODC Parameter Usage Vocabulary, which is available at: http://seadatanet.maris2.nl/bandit/browse_step.php . Each measurement value has a quality flag indicator. The resulting data collections for each Sea Basin are harmonised, and the collections are quality controlled by EMODnet Chemistry Regional Leaders using ODV Software and following a common methodology for all Sea Regions. Harmonisation means that: (1) unit conversion is carried out to express contaminant concentrations with a limited set of measurement units (according to EU directives 2013/39/UE; Comm. Dec. EU 2017/848) and (2) merging of variables described by different “local names” ,but corresponding exactly to the same concepts in BODC P01 vocabulary. The harmonised dataset can be downloaded as ODV spreadsheet (TXT file), which is composed of metadata header followed by tab separated values. This worksheet can be imported to ODV Software for visualisation (More information can be found at: https://www.seadatanet.org/Software/ODV ). The same dataset is offered also as XLSX file in a long/vertical format, in which each P01 measurement is a record line. Additionally, there are a series of columns that split P01 terms in subcomponents (measure, substance, CAS number, matrix...).This transposed format is more adapted to worksheet applications users (e.g. LibreOffice Calc). The 20 parameter names in this metadata record are based on P02, SeaDataNet Parameter Discovery Vocabulary, which is available at: http://seadatanet.maris2.nl/v_bodc_vocab_v2/vocab_relations.asp?lib=P02 . Detailed documentation will be published soon. The original datasets can be searched and downloaded from EMODnet Chemistry Download Service: https://emodnet-chemistry.maris.nl/search