Dependence of lightning current on resistance and radius of discharge plasma channel

The current transmission characteristics of lightning discharge are closely related to lightning hazard mechanisms. The conductive properties of a lightning plasma channel were analyzed based on the spectra of nine negative cloud-to-ground lightning events recorded by a high-speed slit-less spectrograph and the theory of plasma conductivity. Combined with the information of synchronous electric field change caused by lightning, we estimated the peak current and corresponding current-carrying channel radius and further investigated the dependence of the discharge current on the resistance and radius of the discharge plasma channel. The results showed that there was a nonlinear relationship between the peak current and the resistance per unit length of the discharge channel. The radius of the current-carrying channel was positively correlated with the current intensity. Radius was an important parameter that affects the magnitude of the current. The electrical conductivity and the radius of the current-carrying channel have a coupling effect on the current transmission, which is the main factor determining the current transmission feature in the discharge plasma channel. Published under an exclusive license by AIP Publishing.