桂林市暴雨强度公式的推导与研究

Derivation and Research on Rainstorm Intensity Formula for Guilin City

利用桂林国家气象站1957—2014年的自记雨量记录,采用年最大值法的选样方法,选取每年11个短历时的最大雨量记录,建立暴雨强度公式的统计样本;利用皮尔逊-Ⅲ型(P-Ⅲ型)分布、耿贝尔分布和指数分布3种频率分布曲线对统计样本进行拟合,利用最小二乘法和高斯牛顿法推导暴雨强度公式,并进行精度检验。结果表明,P-Ⅲ型分布和耿贝尔分布频率曲线拟合效果优于指数分布;基于P-Ⅲ型分布推导的暴雨强度公式精度明显优于耿贝尔分布和指数分布;利用最小二乘法推导的暴雨强度公式精度明显优于高斯牛顿法;暴雨强度区间参数公式精度优于暴雨强度总公式。

Using serf-recording precipitation records of the Guilin national weather station from 1957 to 2014, adopting the annual maximum sam- piing method, selecting maximum rainfall record of 11 short durations in every year, statistical sample of rainstorm intensity formula was obtainod. Fitting of distribution curve was carried out with P-Ⅲ, Gumbel and exponential distribution, rainstorm intensity formula was derived by the least square method and Gauss Newton method, then the accuracy of results was inspected. The results showed that, the fitting effect of P-Ⅲ and Gumbel distribution curve are superior to index distribution. The accuracy of rainstorm intensity formula derived by the least square method is better than the Gauss Newton method; the rainstorm intensity formula of parameters precision is superior to the rainstorm intensity formula.