Regional comprehensive drought disaster risk dynamic evaluation based on projection pursuit clustering

We used system theory to analyze the structure of a regional drought disaster system and separated the drought disaster risk system into three subsystems. These were drought disaster-causing factors, disaster-inducing environments, and disaster-bearing bodies. Analysis of the main factors of these subsystems allowed the establishment of a regional comprehensive drought disaster risk evaluation index system. To simultaneously evaluate the distribution and development trends of the regional comprehensive drought disaster risk, we established a dynamic evaluation model. Based on the ideas of the projection pursuit clustering method and the dynamic comprehensive evaluation method, the model can make use of multi-dimensional space-time drought disaster information. The model was applied to evaluate comprehensive drought disaster risk in the Xuzhou region, China. The evaluation results show that the method was able to illustrate the development trend and distribution of the comprehensive drought disaster risk in the Xuzhou region. The clustering zoning results show that Pizhou City is the area with the highest risk in Xuzhou, while Fengxian has the lowest. The development trend of comprehensive drought disaster risk with time is not significant.