Assessment and enhancement of flood disaster response capability in Changchun City based on multi-source data

To enhance the flood disaster response capability of Changchun City, a comprehensive evaluation indicator system for flood disaster response capability was constructed based on the pressure-state-response conceptual model. This system deconstructed the urban flood disaster system into three subsystems: pressure (P), state (S), and response (R), corresponding to disaster causes, loss status, and response measures, respectively. A total of 4, 6, and 4 core evaluation indicators were carefully selected for each subsystem. The entropy weight method was applied to calculate the temporal weights of each subsystem in Changchun City from 2002 to 2021, and the coupling coordination degree (CCD) model was used to analyze the dynamic coordination relationship between the S subsystem and the P and R subsystems. The results indicate that the P and R subsystems exhibit significant linear growth trends, reflecting increasing disaster-inducing pressures and enhanced response capabilities in the city, while the S subsystem does not show a clear trend. During 2010, 2013, and 2017, varying degrees of imbalance or declines in CCD have been observed between the S subsystem and the P and R subsystems, which closely coincide with relatively high precipitation levels during those years. The urban flood disaster response capability is significantly influenced by heavy rainfall, necessitating the synergistic integration of engineering and non-engineering technical strategies, as well as the optimization of urban planning, construction, and management strategies, so as to improve system coordination and disaster response effectiveness.