This dataset represents the integrated assessment of hazardous substances in the Baltic Sea in 2016-2021. This dataset displays the result of the assessment in HELCOM Assessment unit Level 3 (Division of the Baltic Sea into 17 sub-basins and further division into coastal and offshore areas).

This core indicator evaluates the status of abundance of wintering waterbirds in the Baltic Sea region, here visualized for grazing feeders. The wintering waterbirds are considered to reflect good status when at least 75% of the considered species deviate less than 30% downwards (species laying more than one egg per year) or 20% downwards (species laying one egg per year) from the baseline condition during the reference period 1991-2000. 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 "country" = Country "Group area" = Name of the group area "level_2" = Name of scale 2 HELCOM assessment unit (subbasin) "level_3" = Name of scale 3 HELCOM assessment unit "Area (km2)" = Area of HELCOM assessment unit "coastal" = HELCOM ID of the coastal areas "open_sea" = Open sea assessment unit name "Abundance" = Assessed parameter "Threshold" = Threshold value "Wading feeders" = Results for the category "Wading feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Surface feeders" = Results for the category "Surface feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Pelagic feeders" = Results for the category "Pelagic feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Benthic feeders" = Results for the category "Benthic feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Grazing feeders" = Results for the category "Grazing feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "AULEVEL" = Assessment unit level used for the indicator

This dataset contains integrated eutrophication status assessment 2011-2016, visualized for direct effects (C2_ER). The assessment is done on HELCOM Assessment Unit level 4: HELCOM Subbasins with coastal WFD water type or water bodies. The HEAT 3.0 has been applied for open sea assessment units using HELCOM core indicators and for coastal areas using national WFD indicators. For more information about the methodology, see State of the Baltic Sea report and HELCOM Eutrophication assessment manual. Attribute information: "HELCOM_ID": ID of HELCOM Level 4 Assessment unit "Country": Country / opensea "level_2": Name of HELCOM Level 2 Assessment unit "Name": Name of HELCOM Level 4 Assessment unit "Area_km2": Area of assessment unit Descriptio: Name of assessment unit "C1_N": Criteria 1, number of indicators used for calculating Eutrophication ratio (ER) "C1_ER": Criteria 1, ER "C1_SCORE": Criteria 1, Confidence of ER "C2_N": Criteria 2, number of indicators used for calculating ER "C2_ER": Criteria 2, ER "C2_SCORE": Criteria 2, Confidence of ER "C3_N": Criteria 3, number of indicators used for calculating ER "C3_ER": Criteria 3, ER "C3_SCORE": Criteria 3, Confidence of ER "N": Number of criteria used for calculating overall ER "ER": Overall ER "SCORE": Status confidence "STATUS": Status classification (Good (classes 0-0.5 & 0.5-1.0), Not Good (classes 1.0-1.5, 1.5-2.0 & >2.0), Not assessed) "CONFIDENCE": Final confidence rating (< 50% = low, 50-74 % = Moderate, = 75 % = High) "AULEVEL": Level of assessment units

This dataset represents the Integrated biodiversity status assessment for ringed seals. Status is shown in five categories based on the integrated assessment scores obtained in the tool. Biological quality ratios (BQR) above 0.6 correspond to good status. The assessment is based on the one-out-all-out approach, i.e. the indicator reflecting the worst status in each assessment unit. The status of the ringed seals was assessed using two core indicators: - population trends and abundance of seals - distribution of Baltic seals. This dataset displays the result of the integrated biodiversity status in HELCOM Assessment unit Scale 2 (Division of the Baltic Sea into 17 sub-basins). Attribute information: "HELCOM_ID" = ID of the HELCOM scale 2 assessment unit "Level_2" = Name of the HELCOM scale 2 assessment unit "EcosystemC" = Ecosystem component analyzedSeal species "BQR" = Biological Quality Ratio "Conf" = Confidence of the assessment "Total_indi" = Number of indicators used "Area_km2" = Area of the HELCOM scale 2 assessment unit "D1CX" = MSFD descriptor 1 criteria X "Conf_D1C_1" = Confidence of MSFD descriptor 1 criteria 2 "STATUS" = Status of assessment (0-0.2 = not good (lowest score), 0.2-0.4 = not good (lower score), 0.4-0.6 = not good (low score), 0.6-0.8 = good (high score, 0.8-1.0 = good (highest score))

The Diatom/Dinoflagellate index (Dia/Dino index) reflects the dominance patterns in the phytoplankton spring bloom. It has high relevance for the pathway of the food into the pelagic or benthic food web. In principle, the indicator is applicable in all coastal and open sea assessment units, except lagoons, large river plumes and the Bothnian Bay; however, thresholds for the good status are defined only for the southern and central Baltic Sea up to now. The indicator is not yet agreed as a HELCOM core indicator but is tested in the HOLAS II project for the Eastern Gotland Basin. In this assessment unit, the average Dia/Dino index of the years 2011-2016 was just below the threshold value of 0.5 for good status. The confidence of the indicator evaluation depends on the data frequency. The data have to represent the diatom and dinoflagellate blooms adequately. If the diatom bloom is not sufficiently represented in the data, an alternative Dia/Dino index may be applied, based on silicate consumption data. This indicator is robust; its calculation is simple and traceable. The phytoplankton monitoring is operational in the whole Baltic Sea using methods prescribed in the COMBINE manual. Currently, a high quality of the data is assured by the experts of the HELCOM Phytoplankton Expert Group (PEG). The basic data are phytoplankton biomass data, determined as explained in the HELCOM COMBINE manual, originating from the depth of 0 – 10 m. Also silicate data were used that were taken parallel to the phytoplankton sampling. Diatom-dinoflagellate ratio dataset displays the result of the indicator in HELCOM Assessment Scale 2 (Division of the Baltic Sea into 17 sub-basins). Attribute information: "HELCOM_ID" = ID of the HELCOM scale 2 assessment unit "Area (km2)" = Area of the HELCOM assessment unit "Name" = Name of the HELCOM scale 2 assessment unit "Status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Threshold value" = Threshold value of indicator "Unit" = Unit of the indicator "Indicator value" = Result of the indicator "AULEVEL" = Assessment unit level used for the indicator

This core indicator evaluates the status of abundance of wintering waterbirds in the Baltic Sea region, here visualized for wading feeders. The wintering waterbirds are considered to reflect good status when at least 75% of the considered species deviate less than 30% downwards (species laying more than one egg per year) or 20% downwards (species laying one egg per year) from the baseline condition during the reference period 1991-2000. 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 "country" = Country "Group area" = Name of the group area "level_2" = Name of scale 2 HELCOM assessment unit (subbasin) "level_3" = Name of scale 3 HELCOM assessment unit "Area (km2)" = Area of HELCOM assessment unit "coastal" = HELCOM ID of the coastal areas "open_sea" = Open sea assessment unit name "Abundance" = Assessed parameter "Threshold" = Threshold value "Wading feeders" = Results for the category "Wading feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Surface feeders" = Results for the category "Surface feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Pelagic feeders" = Results for the category "Pelagic feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Benthic feeders" = Results for the category "Benthic feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "Grazing feeders" = Results for the category "Grazing feeders status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "AULEVEL" = Assessment unit level used for the indicator

This dataset contains data used for the HELCOM Core indicator State of the soft-bottom macrofauna community 2018. Attribute information: "SampleID" = Sample ID "Station" = Station name "Year" = Year of sampling event "Latitude" = Latitude coordinate (WGS84 decimal degrees) "Longitude" = Longitude coordinate (WGS84 decimal degrees) "Depth" = Depth of station (m) "Sentivit" = Sensitivity subset "Sampling_a" = Sampling area (cm2) "Sieve_mesh" = Sive mesh size (microm) "BQI" = Benthic quality index value "Data sourc" = Source of data (national monitoring / other) "Data_origi" = Data providing organization "Country" = Data providing country "Assessment" = HELCOM Level 2 assessment unit where the station resides

This core indicator evaluates the status of the marine environment based on concentrations of radioactive substances (Cs-137) in seawater and biota. Quantitative thresholds are used to evaluate if core indicators status is "Achieve", "Fail" or "Not assessed". Good status is achieved when concentrations reach levels measured before the Chernobyl accident in 1986. This dataset displays the result of the indicator in HELCOM Assessment Scale 2 (Division of the Baltic Sea into 17 sub-basins) for seawater. Attribute information: "HELCOM_ID" = Code of the HELCOM scale 2 assessment unit "level_2" = name of the HELCOM scale 2 assessment unit (subbasin) "area_km2" = Area of HELCOM assessment unit "Indicator" = name of the indicator "Unit" = Unit used for the measured parameter "Type" = type of the indicator "Threshold value" = Threshold value for the subbasin "Indicator value" = Indicator value (result) for the subbasin "STATUS" = Status of the indicator in seawater (“Achieve”, “Fail” or “Not assessed”)

This core indicator evaluates the status of the marine environment based on concentrations of radioactive substances (Cs-137) in seawater and biota. Quantitative thresholds are used to evaluate if core indicators status is "Achieve", "Fail" or "Not assessed". Good status is achieved when concentrations reach levels measured before the Chernobyl accident in 1986. This dataset displays the result of the indicator in HELCOM Assessment Scale 2 (Division of the Baltic Sea into 17 sub-basins) for herring. Attribute information: "OBJECTID" = Object identification "HELCOM_ID" = Code of the HELCOM scale 2 assessment unit "Indicator" = Name of HELCOM Core indicator "Type" = Type of indicator "Threshold value" = Threshold value for specific assessment unit "Indicator value" = Value of indicator calculated for specific assessment unit "Status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”)

This dataset represents the underlying data on core indicator Abundance of waterbirds in the wintering season 2018. Attribute information: "SITECODE_n" =unique site code "YEAR" = year of the observation "SPECIES" = species observed "ABUNDANCE" = Abundance "Country" = Country code "COORD_ X": longitude coordinate of site "COORD_Y": latitude coordinate of station "SITECODE": unique site code with country code