Chemistry

Data & products on marine water quality

Eutrophication

EMODnet Chemistry gives free and open access to data on eutrophication in seawater from all EU basins. More than 600.000 data sets and CDI metadata concerning eutrophication are currently stored in the EMODnet Chemistry portal. The data sets are managed by tens of data centres; a robot harvesting system allows to automatically retrieve from connected data centres all data sets within a configured query filter.

The data sets included in the Portal concern the groups of variables listed in the table below.
Group of variables Examples of used parameters
Chlorophyll Chlorophyll pigment concentration
Dissolved gasses Dissolved oxygen parameters
Fertilisers Ammonium, phosphate, nutrient concentration parameters
Organic matter Carbon concentrations
Silicates Silicate concentration parameters in the water column

The Measurement data, as delivered by the originators, are accessible through the Data Discovery and Access Service. The Service provides relevant metadata, including identifier, data originator and data holding center for all datasets. The data can be downloaded depending on the specific sharing policy (public, restricted, moratorium...) applied by the originator, after user registration and shopping request.

Data collections of standardised, harmonised and validated datasets are available for six sea regions, as shown in the figure on the right. Each regional data collection is accessible through a digital object identifier. The aggregated data are available in ODV csv spreadsheet format, which can be easily handled and visualised with ODV Software. Multiple parameter codes (P01 terms) and associated standard units (P06 terms) are automatically aggregated and standardized by using the EMODnet Chemistry P35 vocabulary.

All datasets have been submitted to a step by step aggregation process. Firstly, they have been prepared and validated using ODV tools. Secondly, data harmonisation and quality assessment have been undertaken per region. Users can find the whole process in the User Manual for aggregated datasets of eutrophication_and ocean acidification.

Visualization products are available through the Map Viewer. The HELP tab provides practical information about the characteristics and functionalities of the system.

Validated data collections have been used as input for preparing spatially interpolated concentration maps, with DIVA (Data-Interpolating Variational Analysis) software. In particular, these products consist in seasonal climatologies built as 6-years running averages. The maps displays the depth-time variability of Ammonium, Dissolved inorganic nitrogen (DIN), Phosphate, Silicate, Chlorophyll � a, Dissolved oxygen concentration. Horizontal sections of the 4-dimensional fields (longitude, latitude, depth and time) can be visualized at a selected depth and time. The climatological fields can also be interpolated and visualized on arbitrary vertical sections.

The products named Plots firstly display location of sampling stations for a single parameter and give information on the number of observations. These maps can be customized selecting both depth and time ranges. Secondly, the maps give access to dynamic plots, time series or vertical profiles, by clicking on the dots representing the sampling stations (figure below on the right). Users can easily customize the plots as well.

Data collections are accessible through the Catalogue Service where users can also retrieve the full set of metadata, originators and distributors.
Detailed information about the methods used for creating the climatologies can be found in User Manual for regional climatologies with DIVA.

EMODnet Chemistry is not responsible of the use of the data and products by third-parties. Users are requested to ensure proper acknowledgment of the EMODnet Chemistry project and the data originators.