Study On Typhoon Disaster Loss Estimation On Typhoon Similarity

The southeast coastal area is one of the most seriously affected by typhoon disaster in China,and because of its high degree of modernization,population density and high wealth density,the loss of the area caused by typhoon is more serious.Therefore,it is necessary for government to make disaster relief decisions,and disaster loss estimation is one of the important links in disaster relief decisions.The establishment of historical typhoon disaster database provides data basis for disaster loss estimation,which is of great significance for government departments to take emergency measures and insurance companies to formulate reasonable insurance policies.Based on the data of historical typhoon disaster loss and the similarity of typhoon characteristics,the study of disaster loss estimation is carried out.The main research contents are as follows:We firstly collect historical typhoon disaster damage data through typhoon disaster statistical yearbooks and typhoon disaster data released by the Ministry of National Emergency Management and the Ministry of Civil Affairs,and further organize and establish a database of historical typhoon disasters.At the same time,based on the statistical analysis results of disaster data from 2003 to 2017 in the database,the temporal and spatial distribution law of typhoon disaster is obtained.We further analyze the disasters and disaster chains caused by typhoons,and can realize the spatial query of typhoon paths and typhoon disasters with the help of GIS software.In order to retrieve a typhoon similar to the target typhoon from the database,it is necessary to define criteria for typhoon similarity.Typhoon similarity includes typhoon path similarity and attribute similarity.The path similarity is calculated by weighted similarity degree,while the path similarity,which includes landing time,typhoon intensity,central lowest pressure and so on,is calculated based on the similarity of each path attribute counted by analytic hierarchy process.The buffer overlay analysis function of Arc GIS software can effectively narrow the retrieval range of historical typhoons,thereby improving the retrieval efficiency of similar paths of typhoons.Since the historical typhoon damage data are calculated based on the socio-economic conditions of the year,in order to use the historical typhoon damage data to estimate the target typhoon disaster loss,the historical typhoon damage data needs to be normalized and corrected.Based on the statistical yearbook CPI(resident price consumption index),urban population density and total crop area of crops,the three typhoon damage indexes including direct economic loss,affected population and affected area,need to be normalized and revised respectively.Taking into account the differences in the ability of disaster relief in different regions,it is necessary to use the total GDP to revise the disaster resistance of each region.Based on the correction of typhoon damage index and regional disaster resistance ability,disaster loss estimation model of single most similar typhoon and the disaster loss estimation model of multiple similar typhoons are established respectively.The model of disaster loss estimation was verified by historical typhoons 1307,1510 and 1720.By comparing with the historical records,the estimated results of the model have good accuracy,and it can estimate the pre-disaster loss of future landing typhoon disasters.