资源环境科技发展态势分析平台

The propagation properties of lightning leader have an important significance for investigating the physical mechanism of lightning process. According to the spectrum and channel pictures of cloud to ground lightning development stage taken by high-speed slit-less spectrograph, the variation characteristics of two-dimensional transmission speed (2-D speed) of lightning leader are analyzed, and their correlation with conductivity and propagation direction of the channel tip are further investigated. The results show that the magnitude of the 2-D speed is roughly proportional to the electrical conductivity of the leader tip, excepting the forked end, which presents comparatively lower values that should be related to the local charge accumulation. In addition, the development direction of the leader tip has obvious influence on the speed value, cosine of the angle between the development direction of the leader and the vertical direction is positive correlated with the propagation speed.