Electric Field Parameters of Natural Negative Cloud-to-Ground Lightning in China

This article presents the electric field characteristics of 1612 single, 912 first, and 2901 subsequent return strokes (RS) in negative lightning in Guangdong Province, China. Statistic parameters of electric field waveforms include risetime, fall time, half-peak width, zero-crossing time, overshoot duration, initial peak, overshoot amplitude, and ratio of initial peak to overshoot (Ep/Eos). The results show that the electric field parameters of single RS are similar to those of the first RS. The difference of the geometric mean (GM) for all the parameters is within 10%, except for the Ep/Eos. The value of Ep/Eos for the first strokes is 14.3% larger than that of the single RS. But the values of these parameters for subsequent RS show significant differences from the single and first RS. The values of overshoot duration for subsequent RS are similar to those of the first RS, while the ratio of initial peak to overshoot is larger. As for the other parameters, the arithmetic mean and GM values are all more than 40% larger than the corresponding values of subsequent RS.