1959～2008年湖北省暴雨的气候变化特征

CLIMATE CHANGE CHARACTERISTICS OF RAINSTORM IN HUBEI PROVINCE DURING 1959～2008

利用湖北省17个气象站1959～2008年逐日降水资料,采用克里格插值法、线性趋势、累计距平、滑动平均及Mann-Kendall、复Morlet小波函数等方法分析湖北省暴雨的空间分布规律和时间演变特征。结果表明:湖北省存在以鄂东南和鄂东北为两个暴雨高值高频中心、鄂西北为低值低频中心的多中心分布特征,整体呈现出从东南向西北递减的地域分布,且大暴雨高频区、特大暴雨多发区和暴雨极大值区均出现在鄂东地区。时间演变趋势上,近50年来湖北省暴雨日数呈弱的增长趋势,暴雨量经历了偏少-偏少-偏多-偏多-偏少的年代际变化过程,异常暴雨年中暴雨日数偏多年较偏少年出现的频率高,全省暴雨日数和暴雨量在1978年发生突变,且存在9 a和5 a的周期振荡,而各分区暴雨日数均表现出显著地8～10 a的年代际周期特征。

Based on 1959～2008 daily precipitation data over 17 stations of Hubei Province,applying the Kriging interpolation method,linear trend,the cumulative anomaly,moving average and the Mann-Kendall,complex Morlet wavelet analysis method the characteristics of the temporal and spatial distribution of torrential rains in Hubei Province were analyzed.The results indicate：Hubei Province＇s storm show a multi-center distribution,there are two storm high-frequency center,which one is in the southeast and the other is in northeast Hubei;one low-frequency center in the northwest Hubei;on the overall it shows a decline from the southeast to the northwest of the geographical distribution;high-frequency heavy rainfall areas,storm-prone areas and maximum rainfall areas appeared in eastern Hubei.On time evolution of trends,Hubei storm days showed weak growth trend in the past 50 years,and experienced below normal-below normal-above normal-above normal-below normal during the interdecadal variation of rainfall amount;the frequency of partial years of heavy rain days is higher than the partial juvenile in abnormal rainstorm;torrential rain days and heavy rainfall across the province the amount of mutation occurred in 1978,and there is 9 years and 5 years of periodic oscillations,and district torrential rain days have shown significant decadal cycle of 8～10 years features.