Temporal analysis on pulse train of lightning discharge observed in Malacca, Malaysia

Abstract

A few significant studies discovered that a pulse train tends to initiate subsequent return stroke in the same way that a preliminary breakdown pulse activates the first return stroke. This paper presents pulse train characteristics in the lightning waveform obtained in Malacca, Malaysia. This study employed 930 pulse train samples divided into twelve groups. Most of the trains are Type IX, i.e., the chaotic pulse train superimposed on the dart leader, accounting for 38% of the samples. There are only 0.8% of Type VI observed in this study. These fewest trains are with regular pulses preceding chaotic pulses without being separated in time. The majority of the pulse train occurred between the first return stroke and the first subsequent return stroke, i.e., 39% of the samples. Averagely, the pulse train time duration was 653µs, and the separation time between pulse train and subsequent return stroke was 25 ms. There was a 99.8% chance that a pulse train would initiate subsequent return stroke. This study revealed that the pulse train and subsequent return stroke separation mean value was decreasing with stroke order. This pattern of pulse train occurrences in the lightning waveform can be manipulated in the lightning monitoring system.