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 dataset represents the Integrated biodiversity status assessment for grey 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 status of the grey seals was assessed using four core indicators: - Population trends and abundance of seals - Distribution of Baltic seals - Nutritional status of seals - Reproductive status of seals. The assessment is based on the one-out-all-out approach, i.e. the indicator reflecting the worst status in each assessment unit. 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 analyzed "BQR" = Biological Quality Ratio "Conf" = Confidence of the assessment "Total_indi" = Number of indicators used "Area_km2" = Area of scale 2 assessment unit "F_of_ar_1" = Share of total area assessed "D1CX" = MSFD descriptor 1 criteria X "conf_D1C_1" = Confidence of the MSFD descriptor 1 criteria 2 "STATUS" = Status assessment category (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))

This dataset represents the underlying biota data on core indicator Polybrominated diphenyl ethers (PBDE) .The core indicator evaluates the status of the marine environment based on concentrations of Polybrominated diphenyl ethers (PBDE) in biota and sediment. Quantitative thresholds are used to evaluate if core indicators status is Achieve, Fail or Not assessed. 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: "region" = name of subbasin "country" = country/ opensea "station" = Unique code for the station "stationNam" = name for the station "determinan" = determinant parameter "detGroup" = the grouping of determinands used to display the results "species" = species of measurement "_shape" = shape used to map assessment results "colou"r = colour used to map assessment results "l3area" = HELCOM assessment unit on scale 3 "l4area" = HELCOM assessment unit on scale 4 "nyall" = total number of years of data "nyfit" = number of years of data used in the assessment "nypos" = number of years with at least one measurement above the limit of detection "lastyear" = most recent year of data "prtrend" = the significance of the change over the most recent 20 years; for the assessment conducted in November 2017 and published in June 2018, this is the period 1996-2016 "rtrend" = annual ‘linear’ change over the most recent 20 years "meanLY" = fitted value in last monitoring year "clLY" = upper one-sided 95% confidence limit on fitted value in last monitoring year "HQS" = Threshold value "HQSdiff" = difference between clLY and HQS "HQSbelow" = whether the mean value in the last monitoring year is significantly below HQS

This core indicator evaluates the status of abundance of breeding waterbirds in the Baltic Sea region. The breeding 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 1 (Whole Baltic Sea). Attribute information: "Status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) "AULEVEL" = Assessment unit level used for the indicator "level_1" = Name of HELCOM scale 1 assessment unit "Common Shelduck" = Results for common shelduck "Eurasian Oystercatcher" = Results for Eurasian oystercatcher "Pied Avocet" = Results for pied avocet "Ringed Plover" = Results for ringed plover "Turnstone" = Results for turnstone "Dunlin" = Results for dunlin "Arctic Skua" = Results for Arctic skua "Common Gull" = Results for common gull "Herrin Gull" = Results for herring gull "Lesser black-backed gull" = Results for lesser black-backed gull "Little Tern" = Results for little tern "Caspian Tern" = Results for Caspian tern "Arctic Tern" = Results for Arctic tern "Goosander" = Results for goosander "Red-breasted Merganser" = Results for red-breasted merganser "Great crested grebe" = Results for great crested grebe "Great Cormorant" = Results for great cormorant "Razorbill" = Results for razorbill "Common Guillemot" = Results for common guillemot "Black Guillemot" = Results for black guillemot "Tufted Duck" = Results for tufted duck "Common Eider" = Results for common eider "Velvet Scoter" = Results for velvet scoter "Mute Swan" = Results for mute swan "Graylag Goose" = Results for greylag goose "Great black-backed Gull" = Results for great black-backed gull "Sandwich Tern" = Results for sandwich tern "Greater Scaup" = Results for greater scaup

This dataset represents the underlying seawater data on core indicator Radioactive substances: Cesium-137 in-fish-and-surface-seawater. The core indicator evaluates the state of the environment using the concentration of the radioactive isotope cesium-137 (137Cs) in herring, in flatfish and in surface waters. Quantitative thresholds are used to evaluate if core indicators Achieve or Fail Good status or if the status is Not assessed. Good status is achieved when concentrations reach levels measured before the Chernobyl accident in 1986 when the biota of the Baltic Sea received the most significant contribution to their level of artificial radionuclides, predominantly in the form of 137Cs. This dataset displays the result of the indicator in HELCOM Assessment Scale 2 (Division of the Baltic Sea into 17 sub-basins). Attribute information: "KEY" = MORS Database unique sample identifier "COUNTRY" = Code for country of observation "YEAR" = Year of observation "STATION" = Unique text that identifies the station "TDEPTH" = Bottom depth at sampling site (m) "SDEPTH" = Sampling depth (m) "ASSESSMENT" = Name of the HELCOM scale 2 assessment unit (subbasin) "NUCLIDE" = Nuclide measured "VALUE_Bq_m" = Value of measurement in Bq/m3

This dataset contains the integrated status assessment for seals (grey seals, harbour seals and ringed seals), harbour porpoise and waterbirds (surface-feeding birds, pelagic-feeding birds, benthic-feeding birds, wading birds, and grazing birds) with bycatch for the HELCOM Third Holistic Assessment of the Ecosystem Health of the Baltic Sea (HOLAS 3). 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 datasets were created using the BEAT tool. https://github.com/helcomsecretariat/BEAT Attribute information for mammals: "level_2" = HELCOM sub-basins (name of the scale 2 assessment unit) "HELCOM_ID" = id of the HELCOM assessment unit "SAUID" = ID number for the spatial assessment unit "SAULEVEL" = spatial assessment unit ID in which the assessment status took place "SAU" = Name the spatial assessment unit "ECID" = Ecosystem component id "EClevel" = Ecosystem component assessed level "EcosystemC" = Ecosystem component assessed "Status" = Integrated status category (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)) "Conf" = Confidence of the assessment (0-1, higher values mean higher confidence) "ConfClass" = Confidence class "BQR" = Biological Quality Ratio "Status_EQR" = Status of the Biological Quality Ratio Attribute information for waterbirds: "Birds_ag" = Birds group area "GroupName" = Birds group area name "level_2" = Name of the HELCOM assessment unit in scale 2 "HELCOM_ID" = Code of the HELCOM scale 2 assessment unit "BQR" = Biological Quality Ratio "Conf" = Confidence of the assessment (0-1, higher values mean higher confidence) "ConfClass" = Confidence class

The assessment results for waterbirds for the HELCOM Third Holistic Assessment of the Ecosystem Health of the Baltic Sea (HOLAS 3) contains the following datasets: Integrated Biodiversity Status Assessment for Waterbirds, Integrated Biodiversity Status Assessment for surface-feeding birds, Integrated Biodiversity Status Assessment for pelagic-feeding birds, Integrated Biodiversity Status Assessment for benthic-feeding birds, Integrated Biodiversity Status Assessment for wading birds, and Integrated Biodiversity Status Assessment for grazing birds. 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 datasets were created using the BEAT tool. https://github.com/helcomsecretariat/BEAT Attribute information: "Birds_ag" = Birds group area "GroupName" = Birds group area name "BQR" = Biological Quality Ratio "Conf" = Confidence of the assessment (0-1, higher values mean higher confidence) "ConfClass" = Confidence class "Status" = Integrated status category (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)) "ProportionSpecies" = Proportion of species in good status "SAUlevel" = Spatial assessment unit ID in which the assessment status took place "EcosystemComponent" = Ecosystem component assessed

This dataset represents the underlying water data on core indicator Heavy metals – Cadmium. The core indicator evaluates the status of the marine environment based on concentrations of heavy metal cadmium (Cd) in seawater, mussels and sediments. Quantitative thresholds are used to evaluate if core indicators status is Achieve, Fail or Not assessed. Threshold values are based on Environmental quality standards (EQS), defined at EU level for substances included in the priority list under the Water Framework Directive. Attribute information: "region" =name of subbasin "country" = country "station" = Unique code for the station "stationNam" = name for the station "determinan" = determinant parameter (CD = Cadmium) "detGroup" = the grouping of determinands used to display the results "filtered" = Filtered or unfiltered water sample used in analysis "_shape2 = shape used to map assessment results "colour" = colour used to map assessment results "l3area" = HELCOM assessment unit on scale 3 "l4area" = HELCOM assessment unit on scale 4 "nyall" = total number of years of data "nyfit" = number of years of data used in the assessment "nypos" = number of years with at least one measurement above the limit of detection "lastyear" = most recent year of data "prtrend" = the significance of the change over the most recent 20 years; for the assessment conducted in November 2017 and published in June 2018, this is the period 1996-2016 "rtrend" = annual ‘linear’ change over the most recent 20 years "meanLY" = fitted value in last monitoring year "clLY" = upper one-sided 95% confidence limit on fitted value in last monitoring year "EQS" = Threshold value "EQSdiff" = difference between clLY and EQS "EQSbelow" = whether the mean value in the last monitoring year is significantly below EQS

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 indicator evaluates the eutrophication status of the Baltic Sea area based on annual total nitrogen concentration. The measured average total nitrogen is derived from in-situ measurements from oceanographic monitoring data for 2011-2016 (µmol/l), surface water (0-10 m). More detailed description on methodology can be found at http://www.helcom.fi/baltic-sea-trends/indicators/total-nitrogen-(tn)/ and http://www.helcom.fi/Documents/Eutrophication%20assessment%20manual.pdf This dataset displays the result of the indicator in HELCOM Assessment Scale 4 (Division of the Baltic Sea into 17 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 and results for coastal areas are based on national WFD results. Some of the open sea areas have not been assessed due to lack of commonly agreed threshold value. Attribute information: “HELCOM_ID” = Code of the HELCOM scale 4 assessment unit "Country" = Country/ Opensea "level_2" = Name of the HELCOM scale 2 assessment unit "Name" = Name of the HELCOM scale 4 assessment unit” "Area (km2)" = Area of the HELCOM scale 2 assessment unit "Indicator" = Name of indicator “Season” = Season of the indicator “Period” = Assessment unit period (20112016 = 2011 – 2016) "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 per assessment unit "Thershold value (ET)" = Commonly agreed thershold value "Ratio between ES and ET (ER)" = 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 "ET_wint" = Commonly agreed thershold value in winter "ER_winter" = Ratio between ES and ET (in case of indicator with positive response to eutrophication) in winter "Winter status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”) in winter