Investigation of Electric Structure of Snowfall-cloud by Simultaneous Observation of Electricity Sonde and Radar

为了研究冬季雷云的大气电性结构，利用电探头和雷达进行了同步观测。该电探头由测量降水粒子上电荷的部分和测量云中大气电位梯度的部分组成。在所获得的7例中的6例中，在云的下部或云底附近观察到电场为正，在云上或云顶附近为负。观察到降水粒子上的电荷符号与电场符号成反比。在最典型的情况下，雷达获得的降水回波(RHI)呈Verga形状，这意味着电荷分离不仅发生在垂直方向上，而且还发生在角面上。因此，云中层的正空间电荷或云上层的正降水电荷可以被认为是对地面的直接揭示。这就是正地放电主要发生在冬季雷云的原因。

To investigate the atmospheric electric structure of winter thunderclouds,some simultaneous observation were carried out by means of electricity sondes and a radar. The electricity sonde is composed of a part of measuring electric charges on precipitation particles and another part of measuring atmospheric electric potential gradient in the clouds.In the six cases of the seven cases obtained, electric fields were observed to be positive in the lower part of the clouds or around cloud bases and negative in the upper part of the clouds or near cloud tops.The sign of electric charge on the precipitation particles were observed to be inverse relation with the sign of electric fields.In the most typical case, precipitation echoes obtained (RHI) by the radar had a verga shape which meaned that charge separation occured not only vertically but also horisontally. Accordingly, positive space charge in the middle level of the clouds or positive precipitation charges in the upper level of the clouds may be considered to reveal for the ground directly. This is the reason why positive ground discharge occurs predominantly in winter thunderclouds.