华南季节干旱及连旱特征分析

 利用1951-2006年实测降水量资料，通过统计方法分析了华南各季节降水量的时空变化及季节干旱特征。结果发现，各季降水量总体上在华南区域空间尺度上有显著的同号变化关系。华南夏季降水量的距平幅度增大，并有增多的长期趋势；秋季降水量则有距平幅度减弱的长期趋势；冬春季降水量的逐年变化存在显著的同相关系。华南秋季发生干旱的频数较其它季节高；春－夏连旱频数较其它季节连旱事件频数要低。

Analysis on Characteristics of Seasonal and Inter-seasonal Drought Events in South China

The characteristics of the spatial and temporal variations of seasonal precipitation and seasonal drought in South China were statistically analyzed with observed data from 1951 to 2006. The variations of seasonal precipitation on the whole regional scale of South China were well in phase. The amplitudes of the seasonal precipitation anomalies became larger in recent years.There existed an increasing trend in the seasonal rainfall for summer and a reversed trend for autumn. The yearly variations of seasonal precipitations in winter and spring were quite consistent with each other. There were more drought events in the fall than in the other seasons, and fewer sustained drought events in the two season period of spring to summer than in the other two season periods.