This dataset is built from the following Human activities dataset: • Hunting of seals The number of hunted seals (see separate metadata on hunting of seals) were averaged over 2011-2014 separately for grey seals, ringed seals and harbour seals (e.g. number of hunted grey seals / year). In Sweden the numbers of hunted grey seals in 2011 (74) were reported for the whole Swedish territorial waters), but here the numbers were set only to Swedish Gulf of Bothnia, as corresponding numbers were reported there in 2013 (75) and 2014 (65). The area of the reporting unit was used to calculate the number of hunted seals / km2 and the data was converted to 1km x 1km grid. For the Baltic Sea Impact Index, the values were normalized. Normalized value 0.5 was set to the level of quota for hunting of seal species in the Baltic Sea. The following quotas for hunting were used: Grey seal: 2000, Ringed seal: 350, Harbour seal 230.

This dataset represents the underlying biota data on core indicator Heavy metals – Mercury.The core indicator evaluates the status of the marine environment based on concentrations of heavy metal Mercury (Hg) in fish muscle. Quantitative threshold value is 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. The Core indicator 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 "station" = Unique code for the station "stationNam" = name for the station "determinan" = determinant parameter (HG = Mercury) "detGroup" = the grouping of determinands used to display the results "species" = species of measurement "_shape" = 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 "HQS" = Threshold value "HQSdiff" = difference between clLY and HQS "HQSbelow" = whether the mean value in the last monitoring year is significantly below HQS

This map shows probability of detection of harbour porpoise (Phocoena phocoena) in the Baltic Sea, for May – Oct. This dataset was produced by the EU LIFE+ funded SAMBAH project and maps the probability of detection of harbour porpoises in the study area, which extends from the Åland Islands in the north to the Darss and Limhamn underwater ridges in the southwest. The study area excludes areas of depths greater than 80 m. Probability of detection was modelled using General Additive Modelling and static covariates such as depth, topographic complexity, month, spatial coordinates and with time surveyed as a weight. Monthly predictions were done on a 1x1 km grid and averaged to result in seasonal distribution maps for May – Oct and Nov – Apr. This division of the year is a result of visual inspection of data and results, showing a clear separation of spatial clusters of harbour porpoises in the summer season May – Oct and a more dispersed pattern with no clear separation in Nov – Apr.

This core indicator evaluates the status of the marine environment based on concentrations of Organobromines HBCDD in sediment. Quantitative threshold value is 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 dataset depicts risk of oil spill from illegal spills. The modeled risk is calculated for the years 2008/2009. The area of the bubbles corresponds to the risk of spill of oil and hazardous substances. The unit of the risk is average tonnes per year. This dataset has been produced by Albrecht Lentz, COWI (http://www.cowi.dk) for the BRISK project (Sub-regional risk of spill of oil and hazardous substances in the Baltic Sea, http://www.brisk.helcom.fi/). The dataset is a model result from a software code owned and operated by COWI. BRISK and BRISK-RU provide information on spatial distribution of risks of pollution from ships in the six sub-regions of the Baltic Sea, according to different types of accidents and spill sizes. The assessment takes into account the existing risk control measures as well as the prognosis for future maritime traffic. Groundings and ship-to-ship collisions are by far the most likely types of accidents resulting in pollution. Other kinds of incidents, such as fire, collisions with fixed objects, spills from offshore platforms, as well as illegal discharges have minor contribution to the risks. Further, the oil impact has been modelled. The oil impact can be described as the amount of spilled oil that is expected on the sea surface. The effects of oil drift, weathering and fate, as well as the oil recovery are taken into account. Field descriptions: LON: Longitude (center of ellipse) LAT: Latitude (center of ellipse) SPILLALL: Risk [average tonnes per year], sum of all spills. Used for visualization. SPILL12: Risk [average tonnes per year], small size spills. SPILL34: Risk [average tonnes per year], medium size spills. SPILL123: Risk [average tonnes per year], small & medium size spills. SPILL4: Risk [average tonnes per year], medium size spills. SPILL1234: Risk [average tonnes per year], small & medium size spills. SPILL567: Risk [average tonnes per year] large spills.

This web mapping service contains datasets on land-based pollutions sources, human activities and aggregated pressure layers used for Baltic Sea Pressures and Impact Index. The service is created with ArcGIS Server 10.6.1 and can be accessed via ArcGIS REST interface or OGC WMS. The service is used by HELCOM Map and Data service.

Large shallow inlets bays (according to Habitats Directive Annex I) are large, shallow indentations of the coast, sheltered from wave action and where, in contrast to estuaries, the influence of freshwater is generally limited. The distribution map is based on data submission by HELCOM contracting parties. Most of the submitted data is based on GIS analysis and modelling, but also field inventories and ground-truthing has been carried out in some areas. Data coverage, accuracy and the methods in obtaining the data vary between countries.

Ecologically or Biologically Significant Marine Areas (EBSA) are special areas in world's oceans that serve important purposes, in one way or another, to support the healthy functioning of oceans and the many services that they provide. Following the voluntary commitment from HELCOM Contracting Parties at the United Nations Oceans Conference in June 2017, HELCOM started the process of identifying EBSAs in the Baltic Sea. The February 2018 EBSA workshop resulted in a proposal for areas for the Convention on Biological Diversity (CBD) to consider during the later half of 2018. Nine Baltic marine areas were described by the workshop participants as ecologically or biologically significant, including five transboundary areas covering waters of two or more countries. The described EBSAs extend into 14 of the 17 Baltic Sea sub-basins. Altogether, they cover 23% of the Baltic Sea, slightly higher than the 19% the average in other areas of the world. The described EBSAs are: - Northern Bothnian Bay - Kvarken Archipelago - Åland Sea, Åland Islands and the Archipelago Sea of Finland - Eastern Gulf of Finland - Inner Sea of West Estonian Archipelago - Southeastern Baltic Sea Shallows - Southern Gotland Harbour Porpoise Area - Fehmarn Belt - Fladen and Stora and Lilla Middelgrund. This dataset contains borders of these 9 areas and related attribute information.

This dataset represents the underlying biota data on core indicator Polyaromatic hydrocarbons (PAH) and their metabolites. The 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 evaluate if core indicators status is 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: "region" = name of subbasin "country" = country "station" = Unique code for the station "stationNam" = name for the station "determinan" = determinant parameter (FLU = fluoranthene, BAP = benzo(a)pyrene) "detGroup" = the grouping of determinands used to display the results "species" = species of measurement "_shape" = 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 "HQS" = Threshold value "HQSdiff" = difference between clLY and HQS "HQSbelow" = whether the mean value in the last monitoring year is significantly below HQS

This indicator evaluates the eutrophication status of the Baltic Sea area based on water clarity measured by secchi depth during summer. The measured average secchi depth (in meters) is based on in-situ measurements from oceanographic monitoring data for 2011-2016 summer months (June-September). More detailed description on methodology can be found at http://www.helcom.fi/baltic-sea-trends/indicators/water-clarity 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. 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 "Method" = Name of method use to define indicator “Season” = Season of the indicator (Summer = June-September) “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 "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 (“Achieve”, “Fail”, “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