Lightning Mechanism and Atmospherics Radiation

Abstract

Simultaneous recording of electro-static field change, waveform of atmospheric, lightning flash photograph, were obtained with partial success during the the thunderstorm observation in summer 1955. The simultaneous records of electro-static field change, and waveform of atmospheric, each pair obtained at the moment of a cloud discharge, have been investigated and the possibilities have been suggested that some of the slow discharge processes in thundercloud will be mainly composed of corona discharges of various types between two charge centres in the cloud. Waveform of atmospheric, and lightning flash photograph, both relating to the same cloud discharge, have made it clear that the very rapid dart leader radiates the atmospheric with waveform of main discharge type. The directly correlated records of electro-static field change, and waveform of atmospheric, were also obtained concerning several ground discharges. This has made it possible to classify the recorded ground discharges into two types according as the discharge has α type stepped leader, or β type, following to the principle orginally reported by Schonland (1). The investigation indicates that no less than 60% of the recorded ground discharges has β type stepped leaders in this thunderstorm season. In spite of the insufficient number of available data at present it seems reasonable to consider that the greater part of the ground discharges in our country have β type stepped leaders.It has also been made clear that the streamer emitting an outstanding single pulse, such as the return streamer of ground discharge, is always associated with secondary and somewhat slow discharge processes.