广州白云国际机场近46年来雷暴气候的统计特征

STATISTIC CHARACTERISTICS OF THUNDERSTORM CLIMATE AT GUANGZHOU BAIYUN INTERNATIONAL AIRPORT IN THE LATE 46 YEARS

利用广州白云机场 1 95 6～ 2 0 0 1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 1 0月 1 4日 ,一年 1 2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 ,1 2月份出现最少 ;雷暴的历史演变有着较好的 9～ 1 2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 。

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.