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Based on the 1961-1990 observed daily precipitation in the Changjiang-Huaihe River Basin,the NCEP/NCAR reanalysis data,and the HadCM3 model data for IPCC SRES A1B climate projections,the simulation capabilities of the BP-CCA downscaling approach for extreme precipitation indices of the current climate are assessed by applying canonical correlation analysis (CCA).In addition,future extreme precipitation indices in the middle and late 21st century are projected.The results show that simulation capability of the HadCM3 for regional climate characteristics can be effectively improved by the downscaling approach,with 30％-100％ reduction of the relative errors of the climatological mean state of extreme precipitation indices.However,the downscaling results still show wetter winter and dryer summer than the observation.Under the SRES A1B emission scenario,frequency and intensity of extreme precipitation events are projected to increase,and the estimated increasing rate is higher for extreme precipitation indices than for mean precipitation index; and in summer than in winter.Extreme precipitations in the middle and late 21st century are expected to increase by 14％ and 25％ respectively in winter,and by 24％ and 32％ respectively in summer.