Security risk assessment and visualization study of key nodes of sea lanes: case studies on the Tsugaru Strait and the Makassar Strait

Key nodes of sea lanes are important hubs for global trade and cargo transportation and play important roles in ensuring the safety of maritime transportation and maintaining the stability of the global supply chain. The safety guarantee of key nodes of sea lanes is facing more risks and higher requirements currently because the global shipping industry is gradually recovering. This paper focuses on key nodes of sea lanes, conducting regional security risk assessment and risk spatial scale visualization. A set of security risk assessment and visualization study methods for key nodes of sea lanes is constructed, which includes constructing a security risk assessment index system of key nodes of sea lanes with 25 indicators selected from three risk categories (hazard, vulnerability and exposure, and mitigation capacity) and using geospatial analysis to form the multi-criteria spatial mapping layers and then creating comprehensive risk layers to realize the risk visualization in the strait area by weighted overlaying based on the combined weights calculated by Analytic Hierarchy Process and Grey Relational Analysis. After taking the Tsugaru Strait and Makassar Strait as case studies, the results show that the comprehensive risk layers can effectively present the spatial distribution of security risks of key nodes of sea lanes, reflecting the spatial changes of risk levels (i.e., very low, low, medium, high and very high) and the methods can precisely identify and analyze crucial factors affecting the security risk of key nodes. These findings may strengthen the risk prevention and improve the safety of the navigation environment in the strait to ensure the safety and stability of maritime trade.