[Objective] The research aimed to analyze temporal-spatial variation characteristics of the extreme precipitation days over South China from 1961 to 2010. [Method] Based on the daily precipitation data in meteorological stations over South China, extreme precipitation thresholds were determined according to the percentiles distribution for different stations. Temporal-spatial variation characteristics of the extreme precipitation days over South China were studied by (he methods of fuzzy clustering, trend coefficient, wavelet analysis and cross spectrum analysis, etc. [Result] Four sub-regions were identified over South China. They were respectively Nanling area, Guixi area, Coastal area and Hainan area. Occurrence seasons of the extreme precipitations in each sub-region were significantly different. Extreme precipitation days in four sub-regions all had increase trends, and those of Nanling area and Coastal area were significant. From wavelet analysis and cross spectrum analysis, there were significant periodic variation characteristics. Each sub-region all had significant same-phase evolution trends at the period of 2 - 5 years, but lagging time was different. [ Conclusion ] The research provided background materials for forecast and influence assessment of the extremely heavy precipitation over South China.%[目的]分析1961～2010年华南极端降水日数的时空变化特征.[方法]根据华南地区气象站逐日降水资料,以百分位值定义极端降水阈值,采用模糊聚类、趋势系数、小波分析、交叉谱分析等方法,对华南地区极端降水日数的时空变化特征进行研究.[结果]华南地区极端降水日数可分为4个气候区,分别是南岭区、桂西区、沿海区和海南区,不同区域出现极端降水的季节有明显差异.各区域极端降水日数都有增加的趋势,其中,南岭区和沿海区增加趋势显著.各区域极端降水日数周期变化特征显著,且在2～5年周期上大多具有显著的同位相演变趋势,但落后时间长度不一致.[结论]该研究为华南地区极端强降水的预测和影响评估提供了背景材料.
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