中国内陆高原地区典型雷暴过程的地闪特征及电荷结构反演  

The Characteristics of Cloud-to-Ground Lightning Flashes and Charge Structure of a Typical Thunderstorm in Chinese Inland Plateau

作　　者：张廷龙[1] 郄秀书[2] 袁铁[3] 张广庶[1] 张彤[1] 赵阳[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所西部气候环境与灾害实验室,兰州730000 [2]中国科学院大气物理研究所中层大气与全球环境探测实验室,北京100029 [3]兰州大学大气科学院学院,兰州730000

出　　处：《大气科学》2008年第5期1221-1228,共8页Chinese Journal of Atmospheric Sciences

基　　金：中国科学院知识创新工程重要方向项目KZCX-YW-206;国家自然科学基金资助项目40675008;40325013

摘　　要：利用2002年夏季在青海省大通县进行的雷暴及闪电综合观测实验中所获取的6站GPS同步闪电电场变化资料,对8月4日一次下部具有大范围正电荷区的典型性雷暴过程的雷电特征进行详细研究。利用点电荷模式对16次负地闪和2次正地闪所包含的共65次回击所中和电荷源进行的非线性最小二乘法拟合研究发现,负地闪所中和的负电荷距离地面的相对高度在3-5 km,而两次正地闪所中和的雷暴云电荷在5-6 km的高度,表明该雷暴云呈三极性电荷结构。负地闪单次回击所中和电荷量平均为1.48 C,而两次正地闪都为单次回击且中和的电荷量分别为1.37 C和2.68 C。Six-station measurements on electric field change of lightning flashes were carried out in the sununer of 2002 in Qinghai area [- （37°3. 795′N, 101° 34. 94′E）, 2553. 32 m above sea level], the northeastern verge of the Tibetan Plateau. By using the point charge model, the height and magnitude of charge neutralized by return strokes have been fitted, with the nonlinear least-square method, based on the electric field changes of cloud-to-ground （CG） flashes observed in a typical thunderstorm with larger-than-usual lower positive charge center （LPCC） occurring in the afternoon of 4 August 2002. A total of 65 return strokes in 16 negative CG and 2 positive CG flashes has been analyzed. The results show that the height of charge region neutralized by negative CG flashes ranges from 3 km to 5 km above the ground. For the two positive CG flashes, the neutralized charge region is located in a height range from 5 km to 6 kin. It shows that the thunderstorm has a triple charge structure The average charges neutralized by a negative return stroke and a positive return stoke are about 1.48 C and 2.02 C, respectively.

关 键 词：电荷结构 回击 内陆高原 点电荷模式 

分 类 号：P427[天文地球—大气科学及气象学]