Abstract: Abstract: Based on the daily observational precipitation data of 147 stations in the Yangtze River Basin during 1960-2005 and the simulated daily data of 79 grids from ECHAM5/ MPI-OM in the 20th century, time series of precipitation extremes which contain AM (annual maximum) and MI (Munger index) were constructed. The distributive feature of precipitation extremes was analyzed based on the two index series. Research results show that 1) the intensity and probability of extremely heavy precipitation are higher in the mid-Mintuo River Basin, Dongting Lake area, mid-lower main stream section of the Yangtze River, southeastern Poyang Lake Basin; whereas, intensity and probability of drought events are higher in the mid-lower Jinsha River Basin and the Jialing River Basin; 2) compared with observational data, averaged AM of modeled precipitation is higher but the discrete coefficient of the AM is lower; 3) in spite of certain differences of the spatial distributions between observed and simulated precipitation extremes by applying general extreme value (GEV) and Wakeby (WAK) functions with the method of L-moment estimator (LME) to the precipitation extremes, WAK can fit the probability distribution of precipitation extremes calculated both from observed and simulated data quite well. The WAK could be an important function for estimating the precipitation extreme events under future climatic scenarios.

Key words: precipitation extremes, probability distribution, ECHAM5 model, the Yangtze River Basin