Tracking Oil Spills with Copernicus

 Tracking Oil Spills with Copernicus

Oil spills can have a devastating and destructive impact on the oceans and marine wildlife, having been a major concern in the marine world for years. Copernicus offers real-time monitoring of oil spills from space.

Oil spills can occur as a result of accidents involving ships or oil rigs, or from illegal operational discharges. These incidents can be of different magnitudes: large scale oil spills, which fortunately do not occur so often, or smaller scale oil leakage or oil discharge incidents, which take place regularly. Every year, the amount of oil released (accidentally or deliberately) into the ocean by shipping vessels reaches thousands of tonnes. Copernicus data and services provide products and satellite-based information that helps national authorities detect, monitor and track potential ongoing oil spills, as well as support authorities in clean-up operations. Detections made by synthetic aperture radar (SAR) satellites such as Sentinel-1 are based on the processing of information on the roughness of the sea surface; floating oil has a dampening effect. However, other products or natural phenomena may cause the same effect. Until oil spills are verified, satellite detections are considered to be ‘possible’ oil spills.

Illegal discharge of oil from a vessel captured by a Copernicus Sentinel-1 SAR image in 2019. The vessel appears as a bright spot, whereas the oil discharge appears as a long, linear, dark shape. (Source: Copernicus Maritime Surveillance Overview)

Copernicus Marine Surveillance Service (CMS)

The Copernicus Maritime Surveillance Service (CMS) provides the detection of discharges of oil, assist in identifying the polluting vessels, as well as monitor the evolution of accidental spills during emergencies. It is implemented by the European Maritime Safety Agency (EMSA) on behalf of DG DEFIS and is one of the three components of the Copernicus Security Service. Apart from maritime pollution monitoring, CMS provides a range of other functions to support maritime monitoring and understanding human activities at sea, such as maritime safety and security, situational awareness for fisheries control, customs, law enforcement and many other activities. The CMS service is offered to national authorities and EU bodies working in the maritime domain and covers not only European waters but maritime areas of European interest anywhere in the world. The CleanSeaNet (CSN) service operated by EMSA provides pollution monitoring in European waters (see below), while the CMS service provides this support further afield in areas of European interest.


Since 2007, EMSA has been operating CleanSeaNet, a service which combines synthetic aperture radar (SAR) and optical data with other kinds of information (for example, vessel identification and position information, behavioural patterns and intelligence from users) to monitor oil spills and detect potentially polluting vessels. SAR satellite images are useful to detect oil spills and possible illegal discharges from ships as they appear as long, linear dark shapes in the SAR image, while vessels and oil platforms appear as bright white spots. In 2015, CleanSeaNet started using Copernicus Sentinel-1 satellite imagery, which significantly improved the level of satellite coverage over European waters and reduced costs at the same time, whereas previously available data have to be purchased from commercial operators. Integration of Copernicus Sentinel-1 data improved the detection capabilities of CleanSeaNet and increased the volume of accessible imagery, which allowed for the detection of smaller spills than before.

Real Time Detection

A key feature of both CMS and CleanSeaNet is that services are delivered in near real time. From the moment of satellite overpass, a standard-sized image in European waters can be acquired, processed, analysed and delivered to the end user via a secure interface within 20 minutes. 

Potential deliberate discharge of oil by a vessel captured on a Sentinel-1 image. Vessel position data from the EMSA systems shows the track of the vessel identified as a possible polluter. The potential spill can be seen clearly as a dark feature on the sea surface surrounded by a blue polygon that closely follows the vessel track. (Source: EMSA, 2020)

Safeguarding the world’s seas

Oil spills can have important and devastating environmental and economic effects. It is thus vital for national and international authorities to have access to reliable and timely data to track and monitor (potential) oil spills and potential polluters. Luckily, the Copernicus programme and its services can help keep an eye on the world’s seas by providing models to track and predict how a potential leak would spread, assisting in clean-up operations and detecting the illegal discharge of oil.

Read more

This article is a summary of a longer article that was published in the Copernicus OBSERVER on 16 September 2021. You can read the full article here.

Remco Timmermans

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