Evaluation model of synergy degree for disaster prevention and reduction in coastal cities

Collaborative disaster prevention and reduction in coastal cities is an important measure to enhance disaster prevention capabilities, improve emergency efficiency and reduce disaster losses. Aiming at the problem of coordination assessment of disaster prevention and reduction between coastal cities, combined with the theory of collaborative governance and regional disaster system theory, this paper studies the coordination index system of disaster prevention and mitigation in coastal cities from the aspects of pre-disaster preparation coordination, disaster response coordination and post-disaster recovery coordination. Using principal component analysis to test the feasibility and structural validity of the index system, an evaluation model of synergy degree of disaster prevention and mitigation in coastal cities based on capacity coupling coefficient is constructed. Typhoons, rainstorms, floods, storm surges and red tides which occurred in coastal cities of China from 1990 to 2018 were selected to carry out empirical research. The evaluation results show that the contribution of the disaster response subsystem is higher than that of the pre-disaster preparation subsystem and the post-disaster recovery subsystem. The synergy degree of disaster prevention and mitigation in China’s coastal cities is restricted by the economic level of cities covered by disasters. The coastal cities with higher economic levels have higher coordination of disaster prevention and mitigation. However, in general, the synergy degree of disaster prevention and mitigation in coastal cities in China is low. The research results can provide policy basis for the improvement in the synergy degree of disaster prevention and mitigation in China’s coastal cities.