Synergy of Copernicus optical and radar data for oil spill detection

Oil spills, whether those come from tanker ships or offshore platforms, might potentially be disastrous for the environment as well as for the society both socially and economically. Generally, oil spills are spreading quite easily for hundreds of nautical miles at the sea damaging large areas and causing serious ecological disasters. Numerous accidents such as the Exxon Valdez accident in Alaska in 1989, the Prestige oil spill at the coast of Galicia, Spain in 2002 or the Deepwater Horizon platform oil spill accident in 2010 in the Gulf of Mexico have unfortunately demonstrated the dangerousness of an oil accident. Remote sensing constitutes an effective solution in oil mapping and monitoring. Specifically, Synthetic Aperture Radar (SAR) satellites have already proved their effectiveness in the specific research field. Oil identification and mapping constitutes a key point of the oil prevention research since is an essential step for the quantification of the oil volume and thereafter the development of a spread model. As case study of the specific work it was selected the Agia Zoni II oil spill, which resulted from the wreck of the Agia Zoni II tanker on September 10th, 2017. This work focuses on the best possible in terms of accuracy mapping of the Agia Zoni II oil spill using Sentinel-1 and Sentinel-2 imagery. The mapping was based on the application of three different processing approaches: a) using the oil spill tool, provided by SNAP software, b) using a semi-automatic methodology and c) by applying a sort of classification in Sentinel-1 images. The approaches were compared and evaluated regarding the quality (reliability) of the final product and the required processing time. The validation of the results of the oil spill mapping using different approaches implemented by the digitization of the affected areas utilizing Sentinel-2 data in ArcGIS environment.