Risk Assessment and Mitigation Strategies for Rainstorm-Induced Disaster Chains in Northwest China

The northwest region of China is susceptible to natural disasters that often form disaster chains with multiple intertwined hazards, posing serious threats to the local society. Therefore, it is crucial to analyze the characteristics of local disaster chains, assess their risks, and formulate targeted countermeasures. In this study, we extracted 85 typical disaster events from the disaster news in the northwest region from 2016 to 2023; we found that disaster chains triggered by heavy rain had the highest frequency in terms of word frequency and spatial distribution analysis. A disaster chain network topology diagram was constructed for heavy rain disaster chains in the northwest region considering three aspects: disaster-causing factors, disaster-prone environments, and disaster-bearing entities. Based on complex network theory, a risk assessment model was constructed using three aspects: risk probability, node risk loss, and edge vulnerability. Last, a practical risk assessment for heavy rain disaster chains in the northwest region was conducted. The results indicated that heavy rainfall is linked to high risks of flooding, mudslides, and collapse. In addition, 25 key chains with high-risk values were identified. Based on the risk assessment, engineering and nonengineering measures are proposed for key links and key chains in order to improve the region’s capacity for natural disaster prevention and disposal.