ABSTRACT
From 1949 to 2014 during the past 55 years natural disasters (except earthquake disaster) have led to more than 310,900 deaths and the severest economical loss in China. 1949 typhoon No.6 led to 3700 deaths; 1954 Yangtze River flood led to 33000 deaths; 1956 typhoon induced sea hazards with simultaneous spring tide led to 4925 deaths; 1961 typhoon led to 1159 deaths, destroyed 1100 ships and 11200 hydrological structures. 1963 flood led to 5600 deaths; No.12 typhoon-induced sea hazards led to 5000 deaths, destroyed 869 km coastal structures and 4400 ships; 1969 typhoon led to 1554 deaths, destroyed 3033 ships and 256 km coastal and hydrological structures. The typhoon Nina in 1975 induced 1,631 mm rainfall in 3 days. Banqiao dam and downstream 64 reservoir dams collapsed. The flooding resulted in 171,000 deaths, affected 12,000,000 people by flood. The flood spread over more than a million hectares of farmland throughout 29 counties and municipalities. The authors found that, using traditional extrapolation (such as a Pearson type 3 model) was difficult to determine the design return period for the extreme events induced by typhoon. According to the randomness of annual typhoon occurrence frequency along different sea areas, it can be considered as a discrete random variable and typhoon characteristics or typhoon-induced extreme sea events are continuous random variables based on the order statistics and theory of measure, the Compound Extreme Value Distribution (CEVD) can be derived (Liu, 1980). After then the first author was invited to America and firstly used CEVD to study Long term distribution of hurricane characteristics (Liu, 1982).
