CleanSeaNet (CSN) is a satellite-based monitoring system for marine oil spill detection and surveillance in European waters.
[1] As of 2017, CSN has become available in, “23 European Union (EU) coastal member states, two EFTA coastal states, three EU candidate countries, the Dutch Caribbean, the French Antilles, Greenland and finally the European neighbourhood partner countries across the Mediterranean, Black and Caspian seas.”[2] The legal basis for the CSN service is Directive 2005/35/EC on ship-source pollution and on the introduction of penalties, including criminal penalties, for pollution offenses (as amended by Directive 2009/123/EC).
[1] Monitoring European waters is particularly challenging being that the EU is an inundated peninsula with extensive external coastlines and several significant semi-enclosed seas.
During this time, countries found the number of images to be insufficient in order to efficiently locate and deal with accidental or deliberate pollution caused by marine vessels.
Crewed aircraft were also frequently used for surveillance purposes on a small scale; however, it would be costly and inefficient to use them for comprehensive coverage of European waters.
[3] Two oil spills in particular caused by the tanker ships Erika and Prestige played influential roles in the need for a more efficient locating method due to the harsh environmental consequences they created.
When exposed to water for a period of time, the oil creates a water-in-oil emulsion causing an increase in volume and viscosity.
Because it left almost 42,000 birds dead, the spill caused by Erika was named the largest ecological disaster for Europe's seabirds.
[4] In November 2002, the tanker Prestige departed from Ventspils, Latvia carrying 77,000 tons of two different grades of heavy fuel oil.
The consequences include 22,000 dead birds and a total loss of 296.96 million dollars to the Spanish fishing sector between the years 2002 and 2006.
The satellites use radar signals that are able to map a body of water based on the amount of disturbance on the surface from waves and ripples created by ocean winds.
SAR satellites send radar signals that bounce off the water's surface measuring the amount of disturbance.
Netherland officials flew over the area during the times that they were expecting services from CNS and were able to capture footage of the culprit while they were dumping palm oil off the vessel.
The tugboat called Francia collided into the CMA CGM Strauss, which was a container ship holding fuel oil.
French authorities requested assistance from CSN and received six satellite images within 30 hours to keep track of the oil slick that spanned between Genoa and Toulon.