FLOOD AND TYPHOON DISASTERS IN VIET-NAM IN THE HALF-CENTURY SINCE 1950

Disasters in Viet Nam are discussed by compiling recent data on the ge ophysical and social environments, the frequency of disasters, and the values of human and financial losses in 1953-1991. Examinations of ye arly frequency and damages caused by typhoons indicate a relatively in creasing value of losses in spite of a constant or decreasing frequenc y in the decade of the 1980s, meaning inadequate prevention programs. The two successive typhoons in 1985 are described as the most catastro phic disaster for 100 years, in which high waves combined with high ti des destroyed the dike system and flooded a large area in the central part of Viet Nam, which suggests some serious deficiencies in preventi on efforts, especially in coastal areas. Disasters on the coast have b een significant because of the rapid growth of the population in the l ow lands and the destruction of coastal environments, such as coastal erosion caused by a deforestation of mangroves and a short supply of s and. As an example, coastal erosion at Ha Nam Nimh province in the nor thern part of Viet Nam at an average receding speed of around 15 m/yea r is described.