Based On Gis In Typhoon Disaster In The Risk Assessment Study

For near the verge of Northwestern Pacific, the largest typhoon cradle in the world, China has become one of the countries which suffer from the most serious typhoon disaster. Each year, the typhoon induced influence and casualty losses have been the top of all kinds of natural disasters. At present, the most domestic typhoon researches focus on the activities pattern of the tropical cyclone itself, characteristics of route and strength changing mechanism, typhoon rain monitoring and forecast business etc. However, the researches on typhoon disaster risk and loss assessment, and the relationship between typhoon loss and meteorological hazard factors are less. In view of the above situation, the following several aspects of the research were done in this paper:Firstly, combined with typhoon disaster material during 1949 to 2006, Zhejiang, a comprehensive statistic of casualties'population, farmland submerged, housing fall loss and direct economic losses were made. Using disaster index model and disaster classification standard, the typhoons was divided into four levels. Finally, analyzed correlation between the disaster loss and hazard-formative factors and discussed the disaster formation mechanism of Zhejiang. The results show that typhoon disaster-induced loss is related to with maximum daily rainfall, process rainfall and maximum wind.Second, from a view of the disaster systems theory, a comprehensive evaluation factors system and model of the typhoon hazard-formative factors, hazard-affected body, and hazard bearing environment for Zhejiang province was constructed. On the hazard-formative factors aspect, use the information diffusion model to calculate exceeding probability of the typhoon rainstorm and winds factor. On the hazard-affected body aspect, using analytic hierarchy process method, select 12 indexes about population, economy, agriculture, education, the hazard-affected body vulnerability of each county in Zhejiang province was evaluated and regionalized. Finally, using the weighted comprehensive evaluation method, comprehensive typhoon disaster risk index was calculated, and with the help GIS spatial analysis technology, typhoon disaster integrated risk distribution map of Zhejiang was painted, which divided the risk into five level. The verification indicates that the evaluation accuracy can reach 85.71%.