摘要
利用三维强风暴动力—电藕合数值模式,结合闪电定位仪资料、雷达回波资料及降水资料,分析了吉林地区一次雷暴云个例在发生第一次闪电前云内电场的发展情况及微物理变化过程,并与青藏高原一次典型雷暴过程进行了对比。结果表明:云发展成熟时,云中呈现上正下负及云下部次正的三极性分布,主负电荷区稳定在-10℃层附近,次正电荷区浓度较大;上升气流穿过-15℃层之上开始强起电;云中最大电场出现在上升速度达到最大值后回落的阶段;闪电频数与云发展的高度及回波强度有关,回波强度>45 dBz时,云发展越高,闪电频数越大,云顶高度<6 km时,闪电发生较少;青藏高原雷暴具有与我国北方雷暴明显不同的特征。
Using a 3D dynamic-electrification coupled model combined with the data of lightning location system, radar and precipitation, a thunderstorm occurring in Jilin province, is simulated, and the typical thunderstorm activity in Naqu district of Qinghai-Xizang Plateau is compared to each other. The model results show that the tripolar structures are produced when the electric field reaches the breakdown value, and the negative charge region locates near --10℃ temperature level. The strong electric activity begins when the updraft velocity achieves --10- 15℃ temperature level. The appearing time of maximal ascending velocity is and earlier than the appearing time of maximal electric field. The frequency of lightning is relative to the height of the cloud and the intensity of radar echo, and the higher the top of the cloud is, the more the frequency of the lightning is; the lightning takes place less when the top of the cloud lower than 6 km. The character of the Plateau storm is different from that of the thunderstorm take place in the north of China obviously.
出处
《高原气象》
CSCD
北大核心
2009年第2期385-394,共10页
Plateau Meteorology
基金
国家自然科学基金重点项目(40537034)
“十一五”国家科技支撑计划重点项目(2006BAC12B00-01-06)共同资助
关键词
吉林地区
电荷结构
垂直电场
回波强度
闪电定位仪
青藏高原
Jilin province
Charge structure
Vertical electric field
Echo intensity, Lightning location system
Qinghai-Xizang Plateau
