小范围自然降雨空间均匀性的实测改进

Improvement of spatial homogeneity of small scale natural rainfall

为了验证雷达反射因子反演小范围自然降雨均匀性的准确率,利用144个直径为8.5cm的标准杯采集了5次小范围(2.4m×2.4m)自然降雨的数据,并对采集范围内降雨的质量分布进行了判别,同时结合克里斯琴森均匀度系数、单因素方差分析模型和偏态系数等数学方法对自然降雨的空间均匀性进行研究,阐述了利用雷达反射因子反演降雨参数时存在的主要问题,分析了误差产生的来源。结果表明:小范围自然降雨的降雨量服从正态分布以及伽马分布,其整体空间均匀性系数一般为97%~99%,说明自然降雨在小范围空间的均匀性较好;同时按照不同方法划分的子空间之间的均匀性差异不显著,证明利用雷达反射因子反演小范围自然降雨的空间均匀性存在很大的误差。

To verify the accuracy of using radar reflection factor and multifractal algorithm to study the uniformity of natural rainfall in small scale,144＂standard cup＂was used to collect the small range（2.4m×2.4m）of natural rainfall data five times and discriminate the rainfall distribution criterion.Christiansen uniformity coefficient was combined with single factor variance analysis modle and skewness coefficient to study the natural rainfall uniformity.Brief reviews were conducted of the main problems of inverting rainfall parameters with radar reflection factor,and at the same time the cause of the error analysed.Results show that the small scale natural rainfall obeys normal and the gamma distribution,and that the overall uniformity coefficient is commonly 97%~99%.There is no significant difference between the partial and local uniformity,and it also proves that using the rader reflection factor to inversion small range of natural rainfall uniformity has a large error.