Multifactorial risk mapping of oil spill accidents for emergency response areas at regional, national and international scales

Quantification and mapping of oil spill risk are essential for emergency response and mitigation of marine accidents. Large-scale risk management involves geographical identification of hazards and sensitivities in coastal and offshore regions. In this study, a multifactorial oil spill risk model was developed on a national scale by determining the frequency (probability) and sensitivity (severity) of marine and coastal accidents. Seven accident frequency and 51 sensitivity factors were investigated within the Turkish Emergency Response Area (TERA) of 660,908 km². Hydrographical, meteorological, oceanographical, and maritime conditions were analyzed to calculate accident frequency. The sensitive areas were mapped using the geographical distribution of ecologic, social, and economic assets. Using data analytics, digital maps of accident frequency, sensitivity and risk were produced in a GIS grid of 21,410 cells with 3NM resolution. Accident hotspots were identified from scalable frequency maps showing regions of high accident probability. Sensitivity factors were analyzed from environmental, social, and economic vulnerabilities. Using their geographic distribution, a sensitivity map was generated and hotspots were identified. Frequency and sensitivity indices were combined to obtain the grid-based high-resolution oil spill risk map on a scalable GIS platform. High-risk areas were identified for future research on oil spill simulations and emergency response plans. The methodology may help scientists and environmental experts develop regional, national, and global risk assessment tools. The outcomes within the TERA may serve as planning and decision support tools for lawmakers, environmental experts, and oil spill response professionals to manage oil pollution risk across the TERA.