This dataset contains core indicator "TBT and imposex - TBSN in sediment" results developed under the HELCOM Third Holistic Assessment of the Ecosystem Health of the Baltic Sea (HOLAS 3). Attribute specifications and units: "HELCOM_ID" = Code of the HELCOM scale 4 assessment unit "country": country in which the HELCOM assessment unit is located or a mention to an open sea area "level_2" = Name of the HELCOM assessment unit in scale 2 "Name" = Name of the HELCOM assessment unit in scale 4 "Open_sea" = Name of the HELCOM assessment unit in the open sea "F2_Name" = Name of the HELCOM assessment unit "determinan" = Determinat "est" = The estimated mean loge concentration in the assessment unit "se" = The standard error on the estimated mean log concentration in the assessment unit "fit" = The estimated mean concentration in the assessment unit "upper_cl" = Upper one-sided 95% confidence limit on the mean concentration: exp(est + qnorm(0.95) * see) "Status" = Overall Status of the indicator according to one-out-all-out

This dataset represents the underlying data on the core indicator Abundance of waterbirds in the breeding season during HOLAS 3. The data results from a data call carried out by HELCOM for the State of the Baltic Sea report. Spatial data was provided as points, lines, and polygons. Further data in excel format was also provided.

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. In this assessment unit, the average Dia/Dino index of the years 2016-2021 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 "level_2" = Name of the HELCOM scale 2 assessment unit "Indicator_" = Name of the indicator "Period" = Interval of year of the sampling "AnnualSamp" = Assessment average sampling value "Unit" = Unit of the indicator "Type" = Type of indicator (1=monotonic, 2=unimodal, optimal range) "Threshold_" = Threshold value of indicator "Indicator1" = Result of the indicator "Status" = Status of the indicator (“Achieve”, “Fail” or “Not assessed”)

This dataset contains sediment monitoring data reported by Contracting Parties of HELCOM to ICES DOME database and extracted for use in Hazardous substances indicators under the HELCOM Third Holistic Assessment of the Ecosystem Health of the Baltic Sea (HOLAS 3). Attribute specifications and units: series region l3area: HELCOM ID for HELCOM assessment units in scale 3 l4area: HELCOM ID for HELCOM assessment units in scale 4 country station_co: station code station_na: station name station_lo: station long name latitude: latitude longitude: longitude MSTAT WLYTP determinan: determinand determin_1: determinand group basis unit series_typ: series type sym_shape colour n_year_all n_year_fit n_year_pos: n year positive first_year: first year all first_ye_1: first year fit last_year p_nonlinea p_linear p_overall p_linear_t: p linear trend linear_tre: linear trend p_recent_t: p recent trend recent_tre: recent trend detectable: detectable trend mean_last_: mean last year climit_las: climit last year EAC_type EAC_value EAC_diff EAC_achiev EAC_below

This core indicator evaluates the status of the marine environment based on concentrations of polyaromatic hydrocarbons PAHs - Anthracene in sediment. Quantitative thresholds are used to evaluate if core indicators status is "Achieve", "Fail" or "Not assessed". Attribute specifications and units: "HELCOM_ID" = Code of the HELCOM scale 4 assessment unit "country": country in which the HELCOM assessment unit is located or a mention to an open sea area "level_2" = Name of the HELCOM assessment unit in scale 2 "Name" = Name of the HELCOM assessment unit in scale 4 "Open_sea" = Name of the HELCOM assessment unit in the open sea "F2_Name" = Name of the HELCOM assessment unit "determinan" = Determinat "est" = The estimated mean loge concentration in the assessment unit "se" = The standard error on the estimated mean log concentration in the assessment unit "fit" = The estimated mean concentration in the assessment unit "upper_cl" = Upper one-sided 95% confidence limit on the mean concentration: exp(est + qnorm(0.95) * see) "colour" = symbology "Status" = Overall Status of the indicator according to one-out-all-out

Potential effect of continuous noise to mobile species assesses the cumulative potential effect of continuous noise on mobile species and their presence in the HELCOM area. The evaluation is based on the pressure layer on input of continuous noise, combined with information on the distribution of 15 mobile species and their habitats. The thematic analyses on the potential effect of continuous noise to mobile species is calculated for each assessment unit (1 km2 grid cells) and the data set covers the time period 2016-2021. Spatial Pressure and Impact Assessment (SPIA) is the framework for assessing spatial and cumulative pressures and impacts in HOLAS 3, and this analyses present a thematic assessment including only a certain subset of layers. The framework also includes results for the Baltic Sea Impact Index (full cumulative impact assessment), Baltic Sea Pressure Index (full cumulative pressure assessment), and other thematic assessments where a subset of pressure and ecosystem layers are used. For more info please - visit the HOLAS 3 website (http://stateofthebalticsea.helcom.fi/) - download the report thematic assessment of spatial distribution of pressures and impacts 2016-2021 (https://helcom.fi/post_type_publ/holas3_spa) - or check out the HELCOM SPIA online tool to make calculations for any desired combination of pressures and ecosystem layers (https://maps.helcom.fi/website/bsii/). Please scroll down to "Lineage" for a more detailed description of the methodology.

This dataset contains all indicator and assessment results and data for the State of the Baltic Sea (HOLAS II) 2017 version. Final 2018 versions are included separately in HELCOM Map and Data service and metadata catalogue. All datasets for HOLAS II and associated metadata were here compiled. The datasets are: Abundance of coastal fish key functional group cyprinids Abundance of coastal fish key functional group piscivores Abundance of coastal fish species Abundance of salmon spawners and smolt Abundance of waterbirds in the breeding season Abundance of waterbirds in the wintering season Chlorophyll a status Cyanobacterial bloom Dissolved inorganic nitrogen Dissolved inorganic phosphorous Distribution of grey seals Distribution of harbour seals Distribution of ringed seals Eutrophication assessment insitu data Heavy metals – Cadmium (Cd) levels Heavy metals – Lead (Pb) levels Heavy metals – Mercury (Hg) levels Hexabromocyclododecane (HBCDD) levels Integrated biodiversity status assessment for benthic habitats Integrated biodiversity status assessment for fish Integrated biodiversity status assessment for grey seals Integrated biodiversity status assessment for harbour porpoises Integrated biodiversity status assessment for pelagichabitats Integrated biodiversity status assessment for ringed seals Integrated biodiversity status assessment for seals Integrated contamination status assessment Integrated eutrophication status assessment Oxygen det PCB dioxin and furan Perfluorooctane sulphonate (PFOS) Polyaromatic hydrocarbons (PAH) and their metabolites Polybrominated diphenyl ethers Cesium-137 in fish Cesium-137 in flatfish Cesium-137 in herring Cesium-137 in seawater Malformed embryos of amphipods State of the soft bottom macrofauna community TBT and imposex Total nitrogen Total phosphorous Trend in arrival of new non-indigenous species Water clarity Zooplankton mean size and total stock MSTS

This core indicator evaluates the status of the marine environment based on concentrations of polyaromatic hydrocarbons PAHs - Fluoranthene in sediment. Quantitative thresholds are used to evaluate if core indicators status is "Achieve", "Fail" or "Not assessed". Attribute specifications and units: "HELCOM_ID" = Code of the HELCOM scale 4 assessment unit "country": country in which the HELCOM assessment unit is located or a mention to an open sea area "level_2" = Name of the HELCOM assessment unit in scale 2 "Name" = Name of the HELCOM assessment unit in scale 4 "Open_sea" = Name of the HELCOM assessment unit in the open sea "F2_Name" = Name of the HELCOM assessment unit "determinan" = Determinat "est" = The estimated mean loge concentration in the assessment unit "se" = The standard error on the estimated mean log concentration in the assessment unit "fit" = The estimated mean concentration in the assessment unit "upper_cl" = Upper one-sided 95% confidence limit on the mean concentration: exp(est + qnorm(0.95) * see) "Status" = Overall Status of the indicator according to one-out-all-out

This core indicator evaluates the status of the marine environment based on concentrations of polyaromatic hydrocarbons PAHs - Fluoranthene in biota. Quantitative thresholds are used to evaluate if core indicators status is "Achieve", "Fail" or "Not assessed". Attribute specifications and units: "HELCOM_ID" = Code of the HELCOM scale 4 assessment unit "country": country in which the HELCOM assessment unit is located or a mention to an open sea area "level_2" = Name of the HELCOM assessment unit in scale 2 "Name" = Name of the HELCOM assessment unit in scale 4 "Open_sea" = Name of the HELCOM assessment unit in the open sea "F2_Name" = Name of the HELCOM assessment unit "determinan" = Determinat "est" = The estimated mean loge concentration in the assessment unit "se" = The standard error on the estimated mean log concentration in the assessment unit "fit" = The estimated mean concentration in the assessment unit "upper_cl" = Upper one-sided 95% confidence limit on the mean concentration: exp(est + qnorm(0.95) * see) "Status" = Overall Status of the indicator according to one-out-all-out

This core indicator evaluates the status of the marine environment based on concentrations of Polyaromatic hydrocarbons (PAH) metabolites in 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 specifications and units: "HELCOM_ID" = Code of the HELCOM scale 4 assessment unit "country": country in which the HELCOM assessment unit is located or a mention to an open sea area "level_2" = Name of the HELCOM assessment unit in scale 2 "Name" = Name of the HELCOM assessment unit in scale 4 "Open_sea" = Name of the HELCOM assessment unit in the open sea "F2_Name" = Name of the HELCOM assessment unit "determinan" = Determinat "est" = The estimated mean loge concentration in the assessment unit "se" = The standard error on the estimated mean log concentration in the assessment unit "fit" = The estimated mean concentration in the assessment unit "upper_cl" = Upper one-sided 95% confidence limit on the mean concentration: exp(est + qnorm(0.95) * see) "Status" = Overall Status of the indicator according to one-out-all-out