The analysis of precipitation distribution & change of Shan-Shan sector in middle reaches of Yellow River in recent 50years;

With the meteorological and hydrographic data in Songhuajiang and Nenjiang valleyfrom 1951 to 1995, using correlation analysis and empirical orthogonal analysis, the rule ofthe flood and relation between flood and precipitation distribution in this region are dis-cussed.

Based on the annual precipitation data of Chengde city from 1956 to 2000,its precipitation distribution characteristic and change trend were analyzed.

By using 20 meteorology stations anomaly percentage of rainfall data in Sichuan and Chongqing area from June to August, the rainfall distribution patterns of Sichuan basin and its early signals are analyzed.

Firstly, surface observation rainfall data, surface rainfall rate retrieved from TRMM satellite observation and analysis data from NCAR/NCEP were used to compare and analyze the rainfall distribution characteristic of typhoon Haitang(2005) and tropical storm Bilis(2006).

The rainfall distribution caused by the nappe impingement was studied in the hydraulic experiment combined with the stochastic splash numerical model.

Based on the hourly precipitation data of 2 years on the Fujian Huian and Daya bay nuclear power plant sites,the two parameters "precipitation time fraction" and "distribution ratio of precipitation intensity" of the washout factor model are estimated.