Abstract: Based on the daily precipitations and the annual peak discharge of Ankang region in recent 60 years, this paper analyzed the timing characteristics, the mutation characteristics of the extreme precipitation and the correlations between the precipitation and the flood disasters from 1953 to 2011 in Ankang region, using Mann-Kendall test, percentile threshold, moving average, correlation analysis and trend analysis combined with the precipitation indexes provided by WMO. The results showed that the maximum daily precipitation, the extreme precipitation intensity, the number of the extreme precipitation days and the amount of the extreme precipitations in Ankang region all presented waving rising trends in the past 60 years. The mutation of the maximum daily precipitation appeared in 1974 and significantly increased in 1983; the mutation of the number of the extreme precipitation days appeared in 2002 and significantly increased in 2011; the amount of the extreme precipitations and the extreme precipitation intensity both presented rising trends since 1997 but no mutation occurred. Since 1997, particularly from the beginning of the 20th century, the number of the extreme precipitation days, the amount of the extreme precipitations and the extreme precipitation intensity apparently and significantly increased in Ankang region while the total precipitation were decreasing. Therefore, the potential flooding disasters have called for more attentions in the upper reach of the Hanjiang river in Ankang area to build up the ability to ensure the safety of the people’s life and property and the security of the South-to-North Water Diversion Project.

Key words: extreme precipitation, flooding disaster, mutation characteristic, Ankang, upper reach of Hanjiang river