基于人工观测和ADTD系统的嘉兴地区雷暴活动特征分析  

Characteristic Analysis of Thunderstorm Activity in Jiaxing Based on Artificial Observations and ADTD System

作　　者：田德宝[1] 杨群超 盛文斌[1] 

机构地区：[1]嘉兴市气象局,浙江嘉兴314050 [2]平湖市气象局,浙江平湖314200

出　　处：《气象与环境科学》2016年第3期90-96,共7页Meteorological and Environmental Sciences

基　　金：嘉兴市科学技术局科技计划项目"多模式集成预报技术研究及‘两区’农业气象服务应用"(2012BZ6007)资助

摘　　要：利用1973—2013年嘉兴地区6个站点雷暴日逐日观测资料和2007—2013年浙江省闪电监测定位系统ADTD探测的云地闪电资料,运用气候趋势系数、气候倾向率、Morlet小波分析等方法,对嘉兴地区雷暴活动特征进行分析。结果表明:嘉兴地区年平均雷暴日数为28.9天,其中最少为嘉善县的26.4天,最多为桐乡市的32.5天,雷暴天气在中国均属中雷区。雷暴日数年代际差异较大,呈逐年下降趋势,海宁市下降最为明显,每10 a减少1.1天左右。年雷暴日数存在12 a左右的短周期和32 a左右的长周期振荡信号,在12 a时间尺度上的周期振荡特别明显。雷暴日数月变化主要呈单峰型,7月份各地的雷暴日数均处于全年的最高值。雷暴日数的空间分布差异较大,总体上从东北到西南逐渐增加。地闪中负地闪占地闪总数的97%,6—8月是地闪的高发期。地闪频次日变化呈单峰状态分布,13—19时为地闪多发时段。地闪密度有显著的地域性差异,桐乡和海宁东部、海盐南部及嘉兴市区为地闪密度高值区。Based on the daily meteorological data in thunderstorm days from six meteorological sta- tions in Jiaxing from 1973 to 2013, and cloud-to-ground lightning data probed by ADTD lightning location monitoring system in Zhejiang province from 2007 to 2013, the thunderstorm activity characteristics in Jiaxing was analyzed using climate tendency coefficient,climate tendency rate and Morlet wavelet analysis methods. The results show that： Jiaxing is a moderate thunderstorm area in China, the average annual thunderstorm days is 28.9 days, least in Jiashan （26.4 days） , most in Tongxiang （32.5 days）. The number of thunderstorm days （NOTD） has an annual decreasing trend, and the inter-decadal fluctuation of thunderstorm is large,the most obvious decline occurs in Haining（ 1. 1 days per decade）. The NOTD has an oscillation signal, whose short period is about 12 a and long period is about 32 a,the periodic os- cillation on the 12 a time scale is particularly significant. The monthly variation of NOTD has a single-peak characteristic and the largest number occurs in July. The spatial distribution of NOTD has great differences in Jiaxing, which gradually increases from northeast to southwest. The 97% cloud-to-ground lightning flashes are negative. Lightning is prone to occur from June to August. The diurnal variation of cloud-to-ground lightning shows a single-peak characteristic with the peak in 13：00--19：00. The lightning density distribution has obvious regional differences. Eastern of Tongxiang and Haining, southern of Haiyan and Jiaxing urban area are the high lightning density areas.

关 键 词：雷暴日 云地闪电 时空分布 地闪密度 

分 类 号：P427.32[天文地球—大气科学及气象学]