利用四川省148个站点1978—2007年的30年逐日观测资料，对四川省冰雹发生分布情况进行了统计分析。结果表明：冰雹日数高原山地多于盆地，其年际变化主要有准两年和6a的振荡周期；冰雹日数总体呈下降趋势，高原下降趋势更为明显；冰雹发生频率以夏季最多，春、秋季次之，冬季最少；地理位置和海拔高度相近的站点，冰雹发生频率的月际变化特征相似。%By using hail data at 148 stations in Sichuan Province during 1978--2007, the spatial and temporal characteristics of hail days were analyzed. The results show that hail days are more in plateau and mountain areas than basin areas. The number of hail days has declined as a whole, especially in plateau areas. The hail appeared with the highest frequency in summer, less in spring and autumn, and the least in winter. In the interannual variations, the periods of quasi-biennial oscillation and 6-year oscillation are primary. The similar inter-monthly variation in hail days happened to the surrounding stations which have the similar altitudes.
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