西北内陆高原雷暴云电活动与微物理场特征的相关性

The relativity between electric activity and microphysical process in thunderclouds over northwest plateau

摘要:

选取甘肃平凉地区2005年和2007年3次典型的雷暴过程,根据X波段多普勒双偏振雷达提供的偏振参量Z_H、Z_DR、K_DR、ρ_HV和高度H,利用分层决策法对雷暴云内的水凝物粒子进行识别。在此基础上,分析甘肃平凉地区夏季雷暴云微物理和电过程之间的关系,尤其是地面电场、闪电类型与水凝物粒子分布之间的关系,推测了雷暴云内不同类型的水凝物粒子携带的电荷极性,并对该地区的电荷结构特征做了进一步解释。

Abstract:

X-band Doppler and dual-polarization radar were used to measure the three thunderstorm processes in 2005 and 2007 in Pingliang area over northwest plateau.Decision tree method was used to classify the hydrometeors types according to polarimetric variables like Z_H,Z_DR,K_DR and ρ_HV and height H,based on which the relationship between microphysical and electrical characteristics,especially the electrical field on the ground,the formation of low positive charge center and the distribution of hydrometeors was analyzed.Then,the polarities charged by different hydrometeors were inferred and the charge structure of thundercloud in the area is further discussed.