近50年安徽池州市降水序列的统计诊断与分析

Statistical Diagnosis and Analysis for Recent 50 Years Precipitation Series in Anhui Chizhou City

根据安徽省池州市气象站1960~2009年的逐月降水观测资料,利用小波分析、改进R/S法、Mann—Kendall法和滑动t-检验等方法对研究区降水特征及变化规律进行分析研究.结果表明:1.池州市近50a降水呈微弱减少趋势,气候倾向率为-3.8819mm/10a.春秋两季降水呈减少趋势,趋势均不显著;夏冬两季呈增加趋势,其中冬季趋势显著.小波分析表明池州市逐季降水序列存在4~5a的振荡周期,年内降水量夏季最多,冬季最少.2.Hurst指数分析表明各月尺度降水序列均存在一定等级的正持续性/反持续性强度.年季尺度方面,只有夏季具有反持续性,分形维数较大,复杂性程度高.3.突变性检验表明研究区存在两次突变情况:秋季降水序列在1986年左右发生了突变,冬季降水序列在1999年左右发生突变.

Based on the monthly precipitation data during 1960~2009 in Chizhou,the characteristics and changing rules of regional rainfall were analyzed by the means of wavelet analysis,improved R/S analysis,Mann-Kendall and moving-t methods.The results showed that:1.Annual precipitation slightly decreased at a climate tendency of-3.8819 mm/lOa in the recent 50 years.For seasonal series,summer and winter increased.Winter trend was significant.Spring and autumn decreased.Wavelet analysis showed that seasonal series had 4~5a oscillating periods.As for yearly precipitation,the maximum season was summer while the minimum was winter.2.The distribution of Hurst exponent showed that various months had definitely levels of persistence/anti-persistence strength.In the terms of seasonal and annual series,summer was anti-persistent with higher fractal dimensions and complexities while other series were persistent.3.The seasonal precipitation had two abrupt changes occurring in the autumn of 1986 and winter of 1999.