The European Maritime Safety Agency (EMSA) explains its role in support of marine safety, pollution, maritime security & vessel monitoring in a new brochure. EMSA operates maritime information systems to support the maritime monitoring activities of the Commission and Member States. • detect oil pollution and vessels through satellite images. EMSA operates the European oil spill and vessel detection service CleanSeaNet. This service analyses satellite radar images to detect possible oil spills on the sea surface. Oil spills appear as dark shapes on the image.