This dataset contains points of information describing the location and size of spills of mineral oil observed during aerial surveillance flights by HELCOM Contracting Parties during 1998-2023. The data covers detections from fixed-wing aircraft only. Since 2014 Contracting Parties have also reported spills of other substances and unknown substances. The purpose of the regional aerial surveillance is to detect spills of oil and other harmful substances and thus prevent violations of the existing regulations on prevention of pollution from ships. Such illegal spills are a form of pollution which threatens the marine environment of the Baltic Sea area. Further information on detected spills in the Baltic Sea area and HELCOM aerial surveillance activities can be found at http://www.helcom.fi/baltic-sea-trends/maritime/illegal-spills/ and https://helcom.fi/action-areas/response-to-spills/aerial-surveillance/ The dataset contains the following information: Country Year Spill_ID = A unique code which will enable each individual spill to be individually identified FlightType = The type of flight the detection was made during: National = "N", CEPCO = "C", Super CEPCO = "SC", Tour d’Horizon = “TDH” Date = The date of the detection (dd.mm.yyyy) Time_UTC = The time of the detection in UTC (hh:mm) Wind_speed = The wind speed at the time of the detection (m/s) Wind_direc = The wind direction in degrees at the time of the detection (degrees) Latitude = The latitude of the detection (decimal degrees, WGS84) Longitude = The longitude of the detection (decimal degrees, WGS84) Length__km = The length of the detection (km) Width__km = The width of the detection (km) Area__km2_ = The area of the detection (km2) Spill_cat = Spill/pollution category: Mineral Oil = “Oil", Other Substance = "Other substance" , "Unknown substance" = “Unknown” EstimVol_m = If Spill_cat="Oil", then estimated min. volume of oil spill. Volume of the detection confirmed/observed as mineral oil as calculated using the Bonn Agreement Oil Appearance Code using the lower figure (BAOAC minimum) in m3. Vol_Category = Category of the detection: <0,1m3 = “1”, <0,1-1m3 = “2”, 1-10 m3 = “3”, 10-100 m3 = “4”, >100 m3 = “5” Type_substance = If Spill_cat="Other substance" or "Unknown. Product name or type of OS or GAR substances that could be identified (in case of known polluter, or via visual identification - cf. BAOAC Atlas). - Examples for OS: vegetable oils (palm oil sun flower oil, soya oil etc.), fish oil, molasses, various chemicals (methanol, biodiesels/FAME, toluene, paraffines etc.); Examples of GAR: solid cargo residues (e.g. coal residues), plastics, fish nets, … OR "Unknown" (in case the type of substance could not be identified) Polluter = Type of polluter source: Offshore Installation = “Rig”, Vessel = “Ship”, Other Polluter or source (e.g. land based source) = “Other”, Unknown = “Unknwon” (in case of an “orphan” spill that cannot be linked to a polluter) Remarks = Any additional information to inform on particular situations Description of marine litter sightings

This dataset contains borders of the HELCOM MPAs (former Baltic Sea Protected Areas (BSPAs). The dataset has been compiled from data submitted by HELCOM Contracting Parties. It includes the borders of designated HELCOM MPAs stored in the http://mpas.helcom.fi. The designation is based on the HELCOM Recommendation 15/5 (1994). The dataset displays all designated or managed MPAs as officially reported to HELCOM by the respective Contracting Party. The latest related HELCOM publication based on MPA related data is http://www.helcom.fi/Lists/Publications/BSEP148.pdf The dataset contains the following information: MPA_ID: Unique ID of the MPA as used in HELCOM Marine Protected Areas database Name: Name of the MPA Country: Country where MPA is located Site_link: Direct link to site's fact sheet in the http://mpas.helcom.fi where additional information is available MPA_status: Management status of the MPA Date_est: Establishment date of the MPA Year_est: Establishment year of the MPA

This dataset contains the ship accidents in the Baltic Sea during the period 1989 to end of 2023. It is constructed from the annual data collected by HELCOM Contracting Parties on ship accidents in the Baltic Sea and starting from 2019 from EMSA EMCIP Database extraction (for those Contracting Parties that are member of the EU). The accident data has been compiled by the HELCOM Secretariat and EMSA. According to the decision of the HELCOM SEA 2/2001 shipping accident data compilation will include only so-called conventional ships according to the Regulation 5, Annex I of MARPOL 73/78 - any oil tanker of 150 GT and above and any other ships of 400 GT and above which are engaged in voyages to ports or offshore terminals under the jurisdiction of other Parties to the Convention. According to the agreed procedure all accidents (including but not limited to grounding, collision with other vessel or contact with fixed structures (offshore installations, wrecks, etc.), disabled vessel (e.g. machinery and/or structure failure), fire, explosions, etc.), which took place in territorial seas or EEZ of the Contracting Party irrespectively if there was pollution or not, are reported. The dataset contains the following information: Unique_ID = An unique identifier consisting of 4 digit running number and the year of the accident Country Year Date = Date (dd/mm/yyyy) Time = Time of the accident (hh:mm) Location = Location of the accident (open sea / port / port approach, from 2019 -> open sea / port) Acc_Type = Type of accident Colli_Type = Type of collision / contact (with vessel / object) Acc_Detail = More information on the accident CauseDetai = Details on the accident cause Assistance = Assistance after the accident Offence = Offence against Rule Damage = Damage to the ship HumanEleme = Occurrence / Reason of human error IceCondit = Ice conditions CrewIceTra = Crew trained for ice conditions Pollution = Pollution (Yes/No) Pollu_m3 = Pollution in m3 Pollu_t = Pollution in tonnes Pollu_Type = Type of pollution RespAction = Response actions after the accident Cargo_Type = Type of cargo Ship1_Name = Ship 1 identification (Not published after 2018) Sh1_Categ = Ship 1 type (according to AIS category) Sh1_Type = Ship 1 more detail ship type category Sh1_Hull = Ship 1 hull construction Sh1Size_gt = Ship 1 GT Sh1Sizedwt = Ship 1 DWT Sh1Draug_m = Ship 1 draught in meters / category Cause_Sh1 = Cause of accidents from ship 1 Pilot_Sh1 = Presence of pilot on ship 1 Ship2_Name = Ship 2 identification (Not published after 2018) Sh2_Categ = Ship 2 type (according to AIS category) Sh2_Type = Ship 2 more detail ship type category Sh2_Hull = Ship 2 hull construction Sh2Size_gt = Ship 2 GT Sh2Sizedwt = Ship 2 DWT Sh2Draug_m = Ship 2 draught in meters / category Cause_Sh2 = Cause of accidents from ship 2 Pilot_Sh2 = Presence of pilot on ship 2 Add_Info = Additional information Latitude = Latitude (decimal degrees) Longitude = Longitude (decimal degrees) For more information about shipping accidents in the Baltic Sea, see the HELCOM annual reports: https://helcom.fi/helcom-at-work/publications/ https://helcom.fi/media/publications/HELCOM-report-on-Shipping-accidents-in-the-Baltic-Sea-2019-211207-FINAL.pdf