The Relationship between Flood Disaster and Rainfall in Xiangjiang River Basin Bo Chen1,2, Weihua Fang1,2,Peijun Shi1,2, Fei he1,2, Zhiqiang Wang1,2, Hong Xu1,2 1. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of China, Beijing Normal University, Beijing 100875, China; 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs & Ministry of Education, the People’s Republic of China, Beijing 100875, China
[email protected] Flood disaster is one of the most serious natural disasters in China, it has caused numerous deaths and injury, as well as tremendous economic losses, and restricted the local sustainable development sharply. Took the total rainfall and frequency of rainfall events beyond downfall (daily rainfall greater than 25mm) from April to August as indices, the relationship between the rainfall and flood disaster from year 1951 to 1998 in Xiangjiang River Basin was analyzed. Four conclusions were found, 1) an abrupt change of flood disaster degree was detected around year 1981 and since then it climbed up to a more serious state. According to its fluctuation character, the flood disaster degree from 1951 to 1998 can be divided to three phases, namely 1951-1961’s aggravating phase, 1965-1975’s mitigatory phase and 1975-1998’s aggravating phase. 2) The total rainfall and frequency of rainfall events beyond downfall from April to August in recent fifty years have no trend but with inter-decadal fluctuation, based on this their variation can be cut to four periods, namely 1951-1967’s decreasing period, 1967-1977’s increasing period, 1977-1992’s declining period and 1992-1998’s climbing up period.