广州白云国际机场近46年来雷暴气候的统计特征

利用广州白云机场1956～2001年46年的逐时观测资料，通过数理统计和小波分析，揭示出白云机场雷暴气候的演变特征。结果表明:白云机场年平均出现雷暴日数为75.4天，初雷一般在3月1日，终雷一般在10月14日，一年12个月都有可能出现雷暴，其中雷暴多集中出现在4～9月份，以8月份出现最多，12月份出现最少；雷暴的历史演变有着较好的9～12年振荡周期，而且近46年来雷暴的发生有逐渐减小的趋势变化，另外雷暴有明显的季节和日变化特征。

Statistic Characteristics of Thunderstorm Climate at Guangzhou Baiyun International Airport in the Late 46 Years

s The 46-year's hourly observational information from 1956-2001 at Guangzhou Baiyun Airport is used to statistically analyzed the thunderstorm climatic characteristics and the wavelet transform is conducted. The results are obtained as follows: Year-averaged days of thunderstorm emergence at Baiyun Airport is 75.4 days. The early thunderstorm day in a year is generally on March 1, and the last thunderstorm day is generally on October 14. It is possible to occur a thunderstorm in any month a year, but occurring frequency of thunderstorm is much concentrated in April-September, the peak is in August and the minimum is in December. There are conspicuous seasonal and daily variations for the thunderstorm. The variation period of thunderstorm climatology has a 9-12 years, and the frequency is gradually decreased in the last 46 years.