HELCOM regularly produces a Pollution Load Compilation (PLC) which assesses the data collected by the Contracting Parties on total air and waterborne inputs of nutrients and some hazardous substances to the Baltic Sea. PLC are an important part of HELCOM´s assessment system on the status of the Baltic marine environment since 1987. HELCOM Pollution Load Compilation database (HELCOM PLC database) contains waterborne discharge data collected and reported by HELCOM Contracting Parties for annual and periodic assessments of inputs of nutrients and selected hazardous substances in to the Baltic Sea. Description of the data collected in the PLC database is presented in the HELCOM Guidelines for the annual and periodical compilation and reporting of waterborne pollution inputs to the Baltic Sea: http://www.helcom.fi/Lists/Publications/PLC-Water-Guidelines-2019.pdf The database is hosted by Baltic Nest Institute, Stockholm University Baltic Sea Centre.

HELCOM Coastal fish core indicator database (COOL) contains updated data used in coastal fish core indicators for every current monitoring station in the Baltic Sea and information on the latest status assessment for the two coastal fish indicators: http://www.helcom.fi/baltic-sea-trends/indicators/abundance-of-coastal-fish-key-functional-groups/ http://www.helcom.fi/baltic-sea-trends/indicators/abundance-of-key-coastal-fish-species The collection of monitoring data is described in the Monitoring guideline: http://www.helcom.fi/Documents/Action%20areas/Monitoring%20and%20assessment/Manuals%20and%20Guidelines/Guidelines%20for%20Coastal%20fish%20Monitoring%20of%20HELCOM.pdf The database was developed in BalticBoost project (http://www.helcom.fi/helcom-at-work/projects/completed-projects/baltic-boost/) Theme 1: Biodiversity, which focused on developing a biodiversity assessment tool and improving data arrangements for the biodiversity elements where this is limited (e.g. coastal fish, birds and seals) so that a comprehensive assessment of biodiversity in the Baltic Sea can be carried out by 2018. The monitoring data is reported by HELCOM Contracting Parties and reported data is verified annually by HELCOM FISH-PRO group.

This online application serves as a joint regional tool to identify low risk routes for IMO Ballast Water Convention exemptions (A-4) for HELCOM and OSPAR marine areas. Data are provided following the port survey protocol described in the HELCOM/OSPAR Joint Harmonised Procedure. https://helcom.fi/wp-content/uploads/2021/01/HELCOM-OSPAR-Joint-Harmonized-Procedure-for-BWMC-A-4-exemptions_2020.pdf The database contains environmental data recorded from OSPAR and HELCOM ports as well as species observations and applies World Register of Marine Species (WoRMS) taxonomy. The data model used is based on Darwin Core format, with required extensions added. The database can be searched, viewed and downloaded using a specific web application. The whole database can be downloaded as a zipped ESRI File geodatabase. The HELCOM/OSPAR Ballast Water Exemptions Decision Support Tool was further developed in the EU INTERREG Baltic Sea Region project COMPLETE, following work developed with funding through the HELCOM ALIENS 2 and 3 and BALSAM projects by the HELCOM Secretariat and Germany (BSH/Brockmann consult). The data contained in the database are resulting from various sources and contains also historical legacy data from old projects. Main sources are listed below: - HELCOM and OSPAR countries national projects - HELCOM ALIENS 2 - HELCOM ALIENS 3 - HELCOM BALSAM

The aim of HELCOM Biodiversity database is to collate all available species observation data made available by HELCOM Contracting Parties. The database contains +1M species observations and applies World Register of Marine Species (WoRMS) taxonomy. The data model used is based on Darwin Core format, with required extensions added. Species observations are mostly pointwise observations, but also gridded observations are included for some species. The database can be searched, viewed and downloaded using a specific web application. The whole database can be downloaded as a zipped ESRI File geodatabase. Disclaimer: Data in the database is stemming from various sources. While there has been considerable quality assurance efforts, the accuracy of data can not be quaranteed. Note that HELCOM Contracting Parties report open sea observations on zoobenthos, zooplanton and phytoplantkon to ICES Dome database and those observations are not included in HELCOM Biodiversity database. Biodiversity database attribute description is available below: attrribute; type (description): origin_of_data_collection; Text (Origin of data call / data collection project from which the observation has been obtained) aphiaID; Number (WoRMS AphiaID or species which is used to retrieve taxonomy information from WoRMS webservice) scientific_name; Text (Scientific name of the species as reported in source data) taxonomical_status; Text (Taxonomical status of Scientific name according to WoRMS) accepted_name; Text (Accepted name of the AphiaID according to WoRMS) species_group; Text (Species group of the AphiaID) synonyms; Text (Synonyms of AphiaID according to WoRMS) data_source; Text (Data provider organization) subunit; Text (Further explanation about any subunits or groups of the institution that are responsible for the data submission.) field_number; Text (unique identifier, number or text or combination, created at collection time to identify each observation, e.g. sample numbers) count_value; Number: Number of individuals: Count value (integer) count_unit; Text: Unit of count value count_estimate; Codelist: Total, Modelled, Maximum, Minimum, C-POD, Null. If not available, use Null count_method; Text. Count method as free text decimal_latitude; Number (Latitude coordinate of observation location in WGS84 decimal degrees, 6 decimals) decimal_longitude; Number (Longitude coordinate of observation location in WGS84 decimal degrees, 6 decimals) coordinate_uncertainty; Number (The horizontal distance (in meters) from the given decimal_latitude and decimal_longitude describing the smallest circle containing the whole of the Location. Leave the value empty if the uncertainty is unknown, cannot be estimated, or is not applicable (because there are no coordinates). Zero is not a valid value for this term. polygon_id_1x1km; ID of the polygon to which observations are within (EEA grid) polygon_id_2x2km; ID of the polygon to which observations are within (EEA grid) polygon_id_5x5km; ID of the polygon to which observations are within (EEA grid) polygon_id_10x10km; ID of the polygon to which observations are within (EEA grid) data_generalization; Text (Codelist: no data generalization, data aggregation as grid (1x1km), data aggregation as grid (2x2km), data aggregation as grid (5x5km), data aggregation as grid (10x10km), Other, please specify in the "Notes" section) year_collected; Number (Year as in YYYY) month_collected; Number (Month as in MM) day_collected; Number (Day as in DD) start_day_collected; Number (Year as in YYYY, used if not a date for sampling but rather a time frame exists. Starting year for that sampling period) start_month_collected; Number (Month as in MM, used if not a date for sampling but rather a time frame exists. Starting month for that sampling period) start_day_collected; Number (Day as in DD, used if not a date for sampling but rather a time frame exists. Starting day for that sampling period) end_year_collected; Number (Year as in YYYY, used if not a date for sampling but rather a time frame exists. Last year for that sampling period) end_month_collected; Number (Month as in MM, used if not a date for sampling but rather a time frame exists. Last month for that sampling period) end_day_collected; Number (Day as in DD, used if not a date for sampling but rather a time frame exists. Last day for that sampling period) notes; Text (Any other information) citation; Text. If specific citation should be used for observation, it should be described here restriction; Yes/No (No, if no restrictions on use. Yes, if any information restricted for this observation, that cannot be shared freely) restriction_description; Free text (If Restriction=Yes, then describe the reason and type of restriction) information_withheld; Text (Codelist: no information withheld, Location information aggregated, Location information aggregated and more detailed information can be asked from the Institution, Other, please specify in the "Notes" section