Simulation And Prediction Of The Regional Heavy Precipitation Over China

Analyzing the capacity of simulating the daily precipitation by Generalized Linear Statistical Downscaling Methods (GLM), and combining the output data of CanESM2model on the Canadian Center to simulate the daily precipitation of593stations in china (GLM-CanESM2). In addition, simulating the development of the regional heavy precipitation events by Objective Identification Technique for Regional Extreme Events(OITREE), then contrasting to the observation events,in order to assessing the ability of simulating the heavy precipitation by CanESM2model. In addition, the occurrence and development of the regional heavy precipitation events in the future hundred years are also estimated. The main conclusions are as follows:(1) Assessing the results of simulation by GLM shows its ability to simulate daily precipitation. The correlation between the simulation results and observations are outstanding; the simulations are generally greater than the observations with small biases, while the accuracy of simulating no precipitation is much higher. The GLM retrieves main rainfall processes successfully with the smaller error.(2) Analyzing the ability of simulating the daily precipitation using CanESM2data by GLM shows that the correlation coefficients between the simulations and observation are around0.4.(3) Assessing the ability of simulating the heavy precipitation events by GLM-CanESM2indicates that the numbers of simulation events are more than that of observation events. Both simulation events and observation events show that the tendency of the composite intensity and frequency was increasing during past45years. It is found that the simulation event reproduces the observation event well by analysis of the extreme heavy precipitation events in1998.(4) The prediction of the daily precipitation of593stations in the future hundred years in China, show that it is increasing in the future with the tendency32.85mm/100a of annual average precipitation. Both in the winter and in the spring, the precipitation increasing on the whole, only in the Yangtze River Valley and some areas in East China the precipitation are reduced. However, both in the summer and in the spring, the precipitation increasing in the eastern coastal areas and the eastern part of the Southwest, only in the western the precipitation are reduced.(5) The prediction of the occurrence and development of the heavy precipitation events in the future hundred years, show that there are646times heavy precipitation events in China, and the extreme heavy precipitation events increase more than the severe events, while general events and weak events are still more than extreme events and severe events. The variation of the cumulative composite intensity index and the cumulative maximum area display the upward trend, Furthermore, the heavy precipitation events often occur in the summer. In addition, the heavy precipitation events occur on the whole in China in the future hundred years, and extend to the western obviously.