1957-2012年宿州市降水时间变化特征研究

摘要

Based on the precipitation data during 1957-2012 in Suzhou,northern Anhui Province,this paper ana-lyzes the characteristics of precipitation,including precipitation trend,non-uniformity coefficient,concentration de-gree. The results show that:(1)The annual and seasonal precipitation all showed a slow upward trend,but inter-decadal and decadal variation of precipitation was larger. (2)After the sliding test,except for spring,the other seasonal precipitation existed mutations points,respectively,in 1994,2003,1998 and 1968,but these mutations were not obvi-ous. (3)Wavelet analysis indicated annual and seasonal precipitation series existed quasi periodic 2-8 years in Suzhou,Anhui Province in the past 57 years,the annual and summer precipitation in existence for 2 years,3 years and 6 years in spring,4 years in autumn and 2-4 years and 10 years in winter oscillation cycle.%利用宿州市气象站1957-2012年逐月降水资料,运用线性趋势分析、 小波分析和Mann-Kendall法对该区年降水量和季节降水量进行年际和年代际分析,揭示该区降水量时间尺度变化特征,并分析其降水序列的周期变化和突变点.结果表明:(1)57年来宿州市年降水量、季节降水量均呈微弱的增长趋势,降水倾向率最大为0.015 8/10 a,但降水年代、年际变化明显.(2)经滑动t检验,宿州市年降水量和季节降水量除春季外均存在突变点,分别出现在1968、1994、1998、2003年,但上述突变均不明显.(3)小波功率谱结果表明宿州市年降水量和季节降水量均存在着2-8年的准周期.年降水量和夏季降水量存在2年,春季存在3年和6年,秋季存在4年,冬季存在2-4年和10年的震荡周期.