This dataset is the first dedicated SMOS Sea Surface Salinity (SSS) product for the Baltic basin to enhance the science capabilities in the Baltic region and help to fill the gaps and grand challenges identified by the scientific community. These new product has been created under the funded ESA project ITT Baltic+ Salinity dynamics (4000126102/18/I-BG). This basin is one of the most challenging regions for the satellite SSS retrieval. The available EO-based SSS products are quite limited in terms of spatio-temporal coverage and quality. This is mainly due to technical limitations that strongly affect the brightness temperatures (TB), such as the high contamination by interferences and the contamination close to land and ice edges. Moreover, the sensitivity of TB to SSS changes is very low and dielectric models present limitations in this low salinity regime. Baltic+ L4 SSS product comprises 9 years (2011-2019) of daily maps at 0.05 degrees. A detailed explanation of the product algorithms and validation can be found at http://bec.icm.csic.es/doc/BEC_PD_SSS_Baltic_L3_L4.pdf and in the publication: Gonzalez-Gambau et al., “First SMOS Sea Surface Salinity dedicated products over the Baltic Sea“, Earth System Science Data, 2021 We present here the seasonal averaged Baltic+ L4 SSS products for the period 2011-2019. The daily Baltic+ L4 SSS products can be downloaded from the BEC FTP service (sftp://becftp.icm.csic.es) in the directory OCEAN/SSS/SMOS/Baltic/v1.0/L4/daily/

Regional hunting numbers for Grey seals 2011-2014.

The dataset contains total landings of sprat for years 2011-2016 reported per ICES statistical rectangles (tonnes / ICES rectangle) under EU Joint Research Centre’s data collection framework for fisheries data. Russian data extracted from ICES annual reports.

Screening activities for component Hazardous wastes on the Leningrad and Kaliningrad Region territories have been fulfilled within the BALTHAZAR project. The main goal of the Project BALTHAZAR is assistance in protection of the Baltic Sea from pollution through reducing of loading caused by agricultural entities (AE) and hazardous wastes. The component Hazardous wastes is focused on inventory of large landfills and estimation of current regime in hazardous wastes management. The main task of screening was to study impact of large landfills on environment of the Leningrad Oblast and Kaliningrad Oblast and to reveal the landfills causing the main loading on the Baltic Sea with pollutants. Screening results report on Leningrad: http://www.helcom.fi/stc/files/Projects/BALTHAZAR/ScreeningReportForPublication-May2011.pdf Screening results report on Kaliningrad: http://www.helcom.fi/stc/files/Projects/BALTHAZAR/KaliningradScreeningResults-1.pdf

Polluting ship accidents is based on reporting of shipping accidents done by HELCOM Contracting Parties to produce annual within HELCOM MARITIME group. Data was available for 2011-2013

The fishing intensity map displays data provided in C-square (0.05 x 0.05 degrees) converted to 1x1 km raster 2011-2016. The value of raster cell is subsurface swept area ratio. The data does not cover Russian waters.

Digitized from Mariners’ Routeing Guide Baltic Sea ISBN 978-3-89871-771-7 (http://www.helcom.dk/map/). The line features are divided in categories, indicated by the the ZONE_TYPE attribute: 0 - Deep water route areas; 1 - Deep water route center line; 4 - Recommended route center; 6 - Traffic separation line; and 7 - Traffic separation scheme.

Eutrophication, caused by excess input of nutrients, is one of the main threats affecting the Baltic Sea marine environment. Nutrients enter the Baltic Sea as waterborne (riverine inputs from the catchment area and direct discharges from point and diffuse sources in coastal areas) and airborne (atmospheric deposition) inputs. In 2007 HELCOM adopted a nutrient reduction scheme which is based on maximum allowable nutrient inputs (MAI) to reach "good environmental status" and country-wise nutrient reduction targets (CART) to share the burden of reducing nutrient pollution to the sea (HELCOM Baltic Sea Action Plan). Monitoring of nutrient inputs to the sea is important for assessing progress of countries towards their CART and to evaluate the effectiveness of measures to reduce pollution. This dataset displays nutrient loading as produced for http://www.helcom.fi/baltic-sea-trends/indicators/inputs-of-nutrients-to-the-subbasins HELCOM Core indicator: Inputs of nutrients to the subbasins based on HELCOM PLC data. Green colour of PLC subbasin indicates that inputs during 2016 were lower than MAI, red colour when they were higher, while yellow indicates that when taking into account the statistical uncertainty of input data it is not possible to determine whether MAI was fulfilled. The dataset contains following attributes: Basin: Name of PLC Subbasin Maximum allowable nutrient input: Maximum allowable nitrogen input for the subbasin (tons/year) N input including statistical uncertainty 2016: the average nitrogen input during 2016 including statistical uncertainty (tons/year) N input 2016 including statistical uncertainty in % of MAI: proportion of normalized nitrogen input during 2016 compared to MAI (%) Classification of achieving MAI: Classification of achieving MAI is given in colours: green=MAI fulfilled, yellow= fulfilment is not determined due to statistical uncertainty, and red=MAI not fulfilled.

Regional hunting numbers for Ringed seals 2011-2014.

Polluting ship accidents is based on reporting of shipping accidents done by HELCOM Contracting Parties to produce annual within HELCOM MARITIME group. Data were available for 2016-2020. Attribute specifications and units Country Year Date__dd_m: Date (dd.mm.yyyy) Time__hh_m: Time (hh:mm) Latitude: Latitude (decimal degrees) Longitude: Longitude (decimal degrees) Location Ship_1_nam: Ship 1 name, flag Sh1_Categ: Ship 1 type (according to AIS category) Sh1_Type: Details of ship 1 type Sh1_Hull: Hull type (ship 1) Sh1Size_gt: Size (gt) (ship 1) Sh1Sezidwt: Size (dwt) (ship 1) Sh1Draug_m: Draught (m) (ship 1) Ship2_Name: Ship 2 name, flag Sh2_Categ: Shiptype 2 (according to AIS category) Sh2_Type: Details of ship 2 type Sh2_Hull: Hull type (ship 2) Sh1Size_gt: Size (gt) (ship 2) Sh2Sizedwt: Size (dwt) (ship 2) Sh2Draug_m: Draught (m) (ship 2) Cargo_Type Acc_Type Colli_Type Acc_Detail Cause_Sh1 Cause_Sh2 HumanEleme IceCondit CrewIceTra CauseDetail Pilot_Sh1 Pilot_Sh2 Offence Damage Assistance Pollution Pollu_m3 Pollut_t Pollu_Type RespAction Add_Info version F44 original_a original_l original_s original_c