The electrical conductivity of a cloud-to-ground lightning discharge channel

Abstract

Based on the wavelengths, relative intensities and other transition parameters of the lines in cloud-to-ground (CG) lightning return stroke spectra captured by a slitless spectrograph in China, the temperatures and electron densities for 16 discharge channels have been calculated, and the electrical conductivities of the channels have been further obtained using the electrical conducting theory of plasma. The results show that the conductivities for 16 channels are in a range of (1.62–2.27)×104 S m−1. The electrical conductivity chiefly depends on the plasma temperature, and the higher temperatures correspond to the higher conductivities for the discharge channels in the same area. In addition, the data of the electrical conductivity show some regional characteristics. In general, the conductivities in coastal areas are higher than those on plateaus for channels with approximately same temperature. For a given return stroke channel, the conductivities show a weak trend of decreasing with an increase in the height along the channel.