Observations of Modiolus modiolus were collected from the Baltic Sea area for HELCOM Red List species list. The HELCOM Red List of Baltic Sea species in danger of becoming extinct (2013) is the first threat assessment for Baltic Sea species that covers all marine mammals, fish, birds, macrophytes (aquatic plants), and benthic invertebrates, and follows the Red List criteria of the International Union for Conservation of Nature (IUCN). Almost 2800 species were considered in the Red List assessment and about 1750 were evaluated according to the IUCN Red List criteria. Modiolus modiolus has been placed to the Red List category of Vulnerable (VU) species. Dataset for download contains spatial grid of the Baltic Sea. Distribution of the species can be found in corresponding name column. Values are coded: 1 - Present before year 2000 or in 2000, 2 - Present after year 2000, 3 - Present both before and after year 2000.

Observations of Salmo salar were collected from the Baltic Sea area for HELCOM Red List species list. The HELCOM Red List of Baltic Sea species in danger of becoming extinct (2013) is the first threat assessment for Baltic Sea species that covers all marine mammals, fish, birds, macrophytes (aquatic plants), and benthic invertebrates, and follows the Red List criteria of the International Union for Conservation of Nature (IUCN). Almost 2800 species were considered in the Red List assessment and about 1750 were evaluated according to the IUCN Red List criteria. Salmo salar has been placed to the Red List category of Vulnerable (VU) species. The map shows the sub-basins in the HELCOM area where the species is known to occur regularly (HELCOM 2012). Reproduction only takes place in rivers.

Summary Estimated observations of the biotopes AA.E1F1 and AB.E1F1 were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic photic or aphotic shell gravel dominated by vase tunicate (Ciona intestinalis)The HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AA.E1F1 and AB.E1F1 according to HELCOM RED LIST assessment experts:The biotopes are known from German waters in the Baltic Sea, but may also occur in other areas in the southwestern Baltic Sea where the vase tunicate (Ciona intestinalis) occurs. The distribution map indicates the area in the 100 x 100 km grid where biotopes are known to occur. The biotopes may potentially occur in other areas with high salinity on shell gravel covered bottoms, but are currently not known from other locations.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

Observations of Melanogrammus aeglefinus were collected from the Baltic Sea area for HELCOM Red List species list. The HELCOM Red List of Baltic Sea species in danger of becoming extinct (2013) is the first threat assessment for Baltic Sea species that covers all marine mammals, fish, birds, macrophytes (aquatic plants), and benthic invertebrates, and follows the Red List criteria of the International Union for Conservation of Nature (IUCN). Almost 2800 species were considered in the Red List assessment and about 1750 were evaluated according to the IUCN Red List criteria. Melanogrammus aeglefinus has been placed to the Red List category of Near Threatened (NT) species. The map shows the sub-basins in the HELCOM area where the species is known to occur regularly and to reproduce (HELCOM 2012).

This dataset contains all PCB in seawater monitoring station locationsas reported to HELCOM secretariat by HELCOM Contracting Parties by 2016.

Summary Estimated observations of the biotope AB.A1J and AB.M1J were collected from the Baltic Sea area by expert judgements for HELCOM Red List of biotopes, habitats and biotope complexes. Description Baltic aphotic rock and boulders or mixed substrates dominated by sponges (Porifera)The HELCOM Red List of Baltic Sea underwater biotopes, habitats and biotope complexes (2013) is an updated and improved version of the Red List assessment of marine and coastal biotopes and biotope complexes published in 1998. The classification of the report follows the proposed International Union for Conservation of Nature (IUCN) criteria and assessment principals but with some modifications for the Baltic Sea.Altogether, the HELCOM Underwater Biotope and habitat classification (HELCOM HUB) includes 209 biotopes of which 59 were red-listed. Many of the red-listed biotopes are located in deep areas of the Baltic Sea due to oxygen-free nature as well as in the southwestern Baltic Sea due to the salinity restricted distribution of species in certain biotope. The HELCOM assessment relies heavily on expert judgment and inference, and the questionnaire data represents the estimated presence-absence data not in-situ measured data. This must be taken in account when observing the map presentation. The biotopes are shown on the map using the EEA 100 km grid. This dataset displays estimated presence of AB.A1J and AB.M1J according to HELCOM RED LIST assessment experts:The sponge biotopes are distributed along the whole Baltic Sea coastline. But as aphotic stony bottoms are scarce in the South-western and Southern Baltic Sea the biotopes are distributed mainly along the Swedish, Danish, Estonian and Finnish coastline or at some offshore reefs. The higher the salinities, the higher the diversity of the sponges and due to the more erect growth also the diversity of the inhabiting invertebrate and fish communities. The distribution map indicates the area in the 100 x 100 km grid where biotopes are known to occur.(Data (expert judgements) collected in HELCOM RED LIST project, released in May 2013)

This dataset contains results on HELCOM Assessment unit level 4b for dissolved inorganic nitrogen. The information provided represents the data and results from the HELCOM HOLAS 3 indicator evaluation for eutrophication, covering the data period from 2016-2021. Data reported from national monitoring programmes to the HELCOM COMBINE database (hosted by ICES) is utilized for open sea assessment units. Open sea data extraction is carried out by ICES for in-situ (bottle) data creating the underlying assessment dataset [link ]. Coastal assessment units (WFD water types or water bodies) are assessed based on WFD result data reported by countries. Indicator analysis of both open sea and coastal areas is carried out using the HEAT assessment tool (https://github.com/ices-tools-prod/HEAT). This analysis provide the basis of the HELCOM indicator evaluations and are utilized in the HOLAS 3 thematic assessment of eutrophication. Attribute description: ES = Eutrophication Status ES_SD = Standard Deviation ES_N = Number of Observations ES_N_Min = Minimum Number of Observations any given year ES_SE = Standards Error ES_CI = Confidence Interval ET = Eutrophication Target / Threshold ER = Eutrophication Ratio ACDEV = Acceptable Deviation BEST = ET / (1 + ACDEV / 100) EQR = Ecological Quality Ratio EQR_HG = Ecological Quality Ratio High/Good Boundary EQR_GM = Ecological Quality Ratio Good/Moderate Boundary EQR_MP = Ecological Quality Ratio Moderate/Poor Boundary EQR_PB = Ecological Quality Ratio Poor/Bad Boundary EQRS = Ecological Quality Ratio Scaled GTC = General Temporal Confidence STC = Specific Temporal Confindence TTC = Total Temporal Confidence GSC = General Spatial Confidence SSC = Specific Spatial Confidence TSC = Total Spatial Confidence TC = Total Confidence

This core indicator evaluates the status of the marine environment based on concentrations of Polyaromatic hydrocarbons (PAH) in sediment and biota. Quantitative threshold value is used to classify core indicators status in “Achieve”, “Fail” or “Not assessed”. As There is no commonly agreed threshold value for measuring metabolites available, this report only considers concentrations of contaminants. This dataset displays the result of the indicator in HELCOM Assessment Scale 4 (Division of the Baltic Sea into 17 sub-basins and further division into coastal and off-shore areas and division of the coastal areas by WFD water types or water bodies). Attribute information: "OBJECTID" = Object identification "HELCOM_ID" = Code of the HELCOM scale 4 assessment unit "Descriptio" = Description of the HELCOM scale 4 assessment unit "AULEVEL" = Assessment unit level used for the indicator "Contamination ratio biota (FLU)" = Contamination ratio in biota for fluoranthene "STATUS_FLU" = Status of the indicator in biota for benzo(a)pyrene (“Achieve”, “Fail” or “Not assessed”) "Contamination ratio in sediment (ANT)" = Contamination ratio in sediment for anthracene "STATUS_ANT" = Status of the indicator in sediment (“Achieve”, “Fail” or “Not assessed”) "Contamination ratio in biota (BAP)" = Contamination ratio in biota for benzo(a)pyrene "STATUS_BAP" = Status of the indicator in biota for benzo(a)pyrene (“Achieve”, “Fail” or “Not assessed”) "Overall status" = Overall Status of the indicator according to one-out-all-out (“Achieve”, “Fail” or “Not assessed”)

This core indicator evaluates the status of coastal sea areas of the Baltic Sea based on the abundance of sea trout parr in rivers where they breed. The determination of whether good status is reached is based on a comparison of the observed parr densities in rearing habitats with the reference potential parr densities in the specified habitats. This dataset displays the result of the indicator in HELCOM Assessment Scale 3 (Division of the Baltic Sea into 17 sub-basins and further division into coastal and offshore areas). Attribute information: "HELCOM_ID" = ID of the HELCOM scale 3 assessment unit "level_2" = Name of the HELCOM scale 2 assessment unit "level_3" = Name of HELCOM scale 3 assessment unit "ICES Subdivision" = ICES assessment unit number "Area (km2)" = Area of the HELCOM scale 3 assessment unit "Indicator_" = Name of the indicator "Unit" = Unit of the indicator "Type" = 1 = boundary values increase/decrease monotonically, 2 = optimum range indicator "Status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "ConfA" = Confidence of classification "ConfT" = Temporal confidence of classification "ConfS" = Spatial confidence of classification "ConfM" = Methodological confidence of classification "notes" = additional info "AULEVEL" = Assessment unit level used for the indicator

This core indicator evaluates the average chlorophyll-a concentration in surface water (0 – 10 m) during summer (June – September) during the assessment period 2016-2021. The measured average chlorophyll-a is a combined estimate of three types of data: 1) in-situ measurements from oceanographic monitoring data (surface water 0-10 m) and 2) earth observation data. 3) Ferrybox data. More detailed description on methodology can be found at HELCOM Core indicator report at https://indicators.helcom.fi/indicator/chlorophyll/ This dataset displays the result of the indicator in HELCOM Assessment Scale 4b (Division of the Baltic Sea into 19 open sea sub-basins and division of coastal areas to WFD water types or water bodies). The open sea areas have been assessed based on HELCOM Monitoring data, earth observation data and ferrybox data. Results for coastal areas are based on national WFD results reported by HELCOM EG EUTRO. Attribute information: "HELCOM_ID" = Code of the HELCOM scale 4b assessment unit "Country" = Country/ Opensea "level_2" = name of the subbasin "level_4" = Name of the HELCOM scale 4 assessment unit "Area (km2)" = Area of the HELCOM scale 4 assessment unit "Indicator" = Name of indicator “Season” = Season of the indicator (Summer = June-September) “Period” = Assessment period (20162021 = 2016 – 2021) Indicator value (ES) = Indicator value calculated for the assessment unit "Standard deviation (STD)" = Standard deviation of data used for calculating ES "Number of samples " = Number of samples by assessment unit "Theshold value (ET)" = Commonly agreed thershold value "Ratio between ES and ET (ER)" = Eutrophication ratio: Ratio between ES and ET (in case of indicator with positive response to eutrophication) "ES_SCORE” = Confidence based on the data used for calculating ES "ET_SCORE” = Confidence of target-setting procedure "I_SCORE” = Confidence (%) = average of ES-Score and ET-Score "Indicator Weight" = Indicator Weight in integrated eutrophication assessment “Status” = Status of the indicator (“Good”, “Not good”, “Not assessed” or "Not applicable") “Confidence” = Confidence of result based on I-SCORE (“High”, “Moderate” or “Low”) "AULEVEL" = Assessment unit level used for the indicator