河南省旬降水量的标度不变性分析

Scale invariance analysis of the 10-day precipitation in Henan Provice

利用河南省107个气象观测站1961-2012年逐旬降水量资料,分析了河南省旬降水量的时空变化特征,并利用去趋势波动分析方法探讨了河南省旬降水量的标度不变性。结果表明:(1)河南省逐旬平均降水量及其站间均方差52 a平均为20.6 mm和15.4 mm,其概率分布均不服从正态分布,为正偏态分布。(2)河南省逐旬降水量及其站间均方差的累积离差均具有阶段性变化特征,在阶段内均具有极为显著的线性变化趋势,能够通过信度为0.001极显著水平的检验。(3)河南省逐站旬降水量的标度指数均在0.5以下,表明时间序列具有非持久性。河南省旬降水量标度指数空间变异性较小,具有正态分布的特征。

Using the 10-day precipitation data of 107 meteorological stations in Henan Province from 1961 to2012,the variability on temporal-spatial characteristics of mean 10-day precipitation and its standard error among meteorological stations,and the variability on cumulative difference of the mean 10-day precipitation and its standard error among meteorological stations were analyzed with mathematical statistical methods. At the same time,the scale invariance of mean 10-day precipitation were studied with the detrended fluctuation analysis（DFA）method. The results showed that： the mean 10-day rainfall and its standard errors among meteorological stations were 20.6 mm and 15.4 mm,respectively; the skewness coefficients were 2.2 and 2.4,respectively; the sharpness coefficients were 6.1 and 9.8,respectively; the stand error of skewness coefficient and sharp sharpness were 0.06 and 0.11,respectively; therefore,the probability distributions of mean 10-day precipitation and its stand error among meteorological stations were not subject to normal distribution,and subject to positively skew distribution. The cumulative difference of precipitation and its mean standard error among the meteorological stations had the same phase characteristics,and all the stages had the extremely significant linear trends at the 0.001 significant level. The trend rate of mean 10-day precipitation and its standard error among meteorological stations were 49.2 mm·10 d-1and 18.7 mm·10 d-1,respectively. The mean of the scale index in Henan Province were0.34,and the variability of scale index among meteorological stations was very small,which skewness coefficient and sharpness were 0.26 and 0.43,respectively,which standard error of skewness coefficient and sharpness coefficient were 0.23 and 0.46,respectively,thus,the spatial distribution of scale index was in accord with the normal distribution. The scale index of mean 10-day precipitation of meteorological stations in Henan Province were all below 0.5,showed that time series of mean 10-day precipitation had no persistent and the original sequence were inversely related,i.e.,if there was an upward trend in the previous sequence,then it had a downward trend in the future,and vice versa. This also indicated that the inversion frequency of the 10-day precipitation sequence was higher than that of the random process.