摘要
根据黄土高原13条流域的降雨资料，分三种雨型即局地强对流条件引起的小范围、短历时、高强度的局地性暴雨（A型暴雨），峰面型降雨夹有局地雷暴性质的较大范围、中历时、中强度暴雨（B型暴雨），峰面型降雨引起的大面积、长历时、低强度暴雨（C型暴雨）；选用流域面雨量离差系数Cv、流域降雨不均匀系数η和流域最大点与最小点降雨量比值系数α三种指标，分析了次降雨空间分布的不均匀性。
：Based on the 448 single rainfall data of 13 watersheds on the Loess Plateau，the non－uniformity of spatial distribution of rainfall，including individual rainfall amount，individual rainfall intensity，and randomness of rain－storm center are analyzed，by dividing rainfall into three patterns and adapting three indexes． The three indexes are the deviation coefficient of area rainfall Cv，the non－uniformity coefficient of rainfall （η），and the ratio between maximum and minimum rainfall （α）． The result indicated that the uniformity of area distribution of individual rainfall amount is no good，the Cv value is generally 0．3－0．5， the η value is usually 0．6－0．8，the α value is about 20． The main factors，which affect the three indexes，are watershed area and the numbers of rainfall station in the watershed． The uniformity of individual rainfall maximum intensity in different time periods is generally not better than that of individual rainfall amount． It related to the time period，the shorter the time period，the worse the spatial distribution． The randomness of storm center occurrence frequency in the watershed is very high，and the storm center occurrence frequency of any station in the watershed does not exceed 20％．
出处
《水文》
CSCD
北大核心
2001年第2期20-24,共5页
Journal of China Hydrology
基金
国家"九五"科技攻关项目"区域水土流失防治与农业持续发展中重大共性关键问题研究"!(96-004-05-12)
