Oil slicks and spills (HOLAS 2)
Short description
The pressure oil slicks and spills is combination of following datasets: • Illegal oil discharges • Polluting ship accidents Illegal oil discharge data is based on airborne surveillance with remote sensing equipment in the Baltic Sea Area. The area of the detected spills in 2011–2016 was used to represent the pressure. The value of spills under 1km2 were directly given to grid cell, spills over 1km2 were buffered based on estimate spill area. For polluting ship accidents the reported oil spill volumes (m3) in years 2011-2015 were used for the pressure. Some polluting ship accidents spills were missing spilled oil volume, thus a mean of reported volumes was given to accidents with missing oil volume. Datasets were handled separately. Both layers were normalized, summed and normalized again to produce the “oil slicks and spills” pressure layer. Please see below for further details.
Point of contact
HELCOM Secretariat
data@helcom.fi
Spatial extent
['7.818737', '33.903834', '52.502121', '66.484464']
Type
dataset
Metadata information
Identifier
Keywords
Oceanographic geographical features ; GEMET - INSPIRE themes, version 1.0 ;

shipping accident ; oil spill ; environmental impact ; GEMET ;

MADS ; HOLAS2 ;

Resource provider(s)
HELCOM Secretariat
data@helcom.fi

Lineage
Data source: Illegal oil discharges data is based on airborne surveillance with remote sensing equipment by HELCOM Contracting parties in the Baltic Sea Area. Polluting ship accident data is based on data collected annually from HELCOM Contracting Parties. Illegal oil discharges: If oil spill volume was missing, median of the rest was given. If area of spill was missing, mean of the existing was given. If the spill was < 1km2, the value of spill volume was given directly to 1km2 grid cell. If the spill area > 1km2, the estimated volume of the spill was divided by the spill area to get the estimated amount of oil / km2. This value was given to the entire spill area. Polluting ship accidents: 9/24 accidents with oil spills were missing spilled oil volume, thus a mean of reported volumes was given to accidents with missing oil volume. Spill volume was given directly to 1km2 grid cell. Layers were separately normalised (0-1). After that layers were summed and again normalised to produce the final pressure value between 0 and 1. Attribute information: Index value representing pressure from oil spills and slicks, including layers illegal oil discharges and polluting ship accidents. Spatial coverage: Entire Baltic Sea. Spatial resolution: Original data reported as points, finally converted to 1 km x 1 km grid.