Spatial Distribution Characteristics of Oil Spills in the Bohai Sea Based on Satellite Remote Sensing and GIS

In recent years, on account of the vast and persistent damage of oil spill accidents, it becomes essential to carry out a further study on oil spill distribution characteristics on sea. Routine satellite remote sensing surveillance on oil spills with Synthetic Aperture Radar (SAR) proved to be ideal for analyzing distribution of oil pollution in macro scale. In this research work, considering the presence of look-alikes phenomena on SAR images as well as current operational application of confidence level, a confidence-oriented oil spill geodatabase is initially designed and built for quantification analysis. Then, in view of the requirement of marine grid management, a common framework based on remote sensing and Geographic Information System (GIS) is proposed to map and reveal the spatial distribution of oil pollution, in the process of which, oil pollution index (OPI) is put forward to evaluate oil pollution levels, then oil pollution distribution map can be compiled in terms of OPI, and the relationship between oil pollution and oil spill risk source can be further analyzed. Finally, a case study of the Bohai Sea and the north of the Yellow Sea with five-year's inter-annual satellite monitoring data was studied. The results showed that, during the period between 2009 and 2013, the high frequency grids of potential oil spills mainly distributed in the Bohai Bay and the south of the Liaodong Bay. 77.03 % of detected oil spills were within a certain distance along the sea lanes or near the offshore platforms, indicating a high risk of oil pollution of these areas. Generally, this research work also benefits for yield for the first time a rather comprehensive distribution characteristics of potential oil spills in macro scale in the Bohai Sea combined with remote sensing and GIS technique, which will be beneficial for oil spill response, preparedness and risk management.