Reconstruction of lightning channel based on acoustic radiation

Abstract

The acoustic radiation of lightning was used to get information on the lightning channel, such as images and locations. A single station of short baseline lightning location was installed to record the acoustic signals of lightning using a microphone array observation system (MAOS). In this study, the differential time of arrival (DTOA) method was used to examine the time variation in the acoustic signals of lightning and to reconstruct the 3D lightning channel imaging. The results showed that there was good agreement between images recorded by cameras and MAOS. The height of negative charge center in thundercloud is at 4.37-4.83 km. The azimuth and elevation angles of the acoustic radiation source at higher latitude inside a thundercloud of two recorded natural lightning discharges were 70.67o, 90o and 67.83o, 73.82o, respectively. The acoustic signal of thunder lasted about 15.15-16.038 s. The system was able to reconstruct the 3D lightning channel imaging.