Research On Typhoon Disaster Risk In South China Based On Statistical Method

Tropical cyclones are one of the main natural disasters in China.Tropical cyclones landing on the coast of China mainly occur in the northwest Pacific Ocean.Tropical cyclones can be divided into tropical depression,tropical storm,severe tropical storm,typhoon,severe typhoon and super typhoon according to the intensity of wind speed.In recent years,the intensity of tropical cyclones landing in China has been increasing year by year,and the disaster caused by landing typhoons is also serious.As a typical coastal area in South China,tropical cyclones with intensity above and above occur frequently in the three provinces of South China.The disaster caused by typhoon can not be ignored.Typhoon disaster situation is the risk of disaster-causing source,vulnerability and exposure of disaster carrying body,disaster and reduction prevention capacity.The result under the joint action,then,with the change of social attribute and natural attribute,and the danger of disaster superimposed on each other,what kind of influence can it have on the typhoon disaster situation? It is necessary for us to deeply discuss the relationship between typhoon disaster situation and its influencing factors,and then select the appropriate factors to analyze the risk of typhoon disaster in South China.Therefore,the following work has been done in this paper:(1)The basic characteristics of landfall typhoon disaster in South China are studied by means of descriptive statistics based on the intensity,frequency,time,landing and impact area of typhoon landfall in South China.The results show that,compared with 1973-1994,the typhoon landing in three provinces of South China during 1995-2016 has the characteristics of decreasing frequency and increasing intensity.According to the analysis of typhoon landing time in three provinces of South China,it is found that the monthly frequency distribution of typhoon obeys normal distribution,and Guangdong and Hainan provinces are the main landing points of typhoon from the point of landing and the area affected by typhoon.However,45.16%of the typhoon process can cause disasters to the three provinces in South China at the same time.The perimeter is wider.(2)Considering the complex linear and nonlinear relationship between typhoon disaster and influence factors,firstly,the catastrophe theory method is used to construct the typhoon disaster index in South China.Then,the linear Lasso regression and the nonlinear MIV method are usedto analyze the correlation between the disaster condition factor and the influence factor of typhoon landing in South China respectively.Finally,the significant correlation factors affecting typhoon disaster in South China are selected by combining the BIC information criterion and the T-test threshold setting method respectively.(3)Using BP neural network model,using Lasso-MIV combination selection factor as the input of the model,direct economic loss,death population,crop disaster area and disaster index as the output of the model,the prediction experiment of typhoon disaster in South China is carried out.The results show that except for a few singular points,the prediction effect of Lasso-MIV-BPNN model is better.