摘要
通过对宁波地区1973—2014年的雷暴日数统计分析,结果表明,该地区的雷暴日分布呈自西向东逐渐减少的趋势。从年际分析来看,雷暴日数呈逐年减少趋势,以-2.1044d/10年的线性趋势显著减少。除象山外,其他地区均以不同的线性趋势减少。M-K突变检验显示在1989年前后发生了1次显著减少性突变,1989年后的平均雷暴日较突变前平均值减少了近7.53 d。从小波分析来看,宁波地区雷暴日存在24年和14年左右的周期性变化,在较小时间尺度上,雷暴日年际变化存在5年和10年左右的短周期。宁波地区的雷暴日具有明显的季节特征,主要发生在春季和夏季,且夏季最多。
The statistical analysis of the thunderstorm days in Ningbo area during 1973-2014 was conducted. The results showed that the thunderstorm days in Ningbo area tended to decrease gradually from west to east.Based on the annual analysis ,the thunderstorm days decreased year by year,and the decadal linear trend was -2.1044d.The thunderstorm days of the region reduced by different linear trends except Xiangshan.The M-K mutation test showed that one significant reduction occurred suddenly after 1989,and the average thunderstorm days after 1989 decreased by nearly 7.53 days compared with the average value. According to the wavelet analysis,it appeared 2A-year periodic change and 14-year periodic change of thunderstorm days in Ningbo area. In small time scale ,the interannual variation of thunderstorm days showed 5 -year and 10-year short periods.The thunderstorm day in Ningbo had obvious seasonal characteristics,mainly in spring and summer, and summer thunderstorm days were the most.
出处
《现代农业科技》
2017年第17期194-196,共3页
Modern Agricultural Science and Technology
基金
宁波市气象局科技计划项目(NBQX2015007B)
