Analyzing the transmission structures of long continuing current processes from negative ground flashes on the Qinghai‐Tibetan Plateau

Abstract

This paper presents a new overlap and progressive method using either a one-point charge model or a point dipole model for studying the electric field change data of lightning and tests the suitability of the proposed method by analyzing the slow electric field change of the long continuing current data from two negative ground flashes. The current measurements of the ground flashes are from the Composite Observing Experiment for Lightning project carried out in the Datong region of Qinghai Province, China, in 2009, obtained from field observations synchronized through high-precision GPS clocks at seven observation stations. Analysis shows that the time-averaged current can reach 800 A, and the current intensity relates to the height of the top of the return stroke before the continuing current process. The two current processes studied in this work neutralized a large amount of negative charge, 39.5C and 60.8C, respectively. The neutralized charges from the negative charge layer are typically at 2.5-4.7 km above ground. The intracloud transition of the positive leader is a complex process, and the horizontal propagation of the positive leader plays an important role in current duration as well as horizontally influencing the center of the electrical dipole moment with an obvious change of up to 3.0 km. The proposed analysis method is very useful compared to previous methods in terms of determining infinitesimal changes in long continuing currents. This work's new analysis method will help increase understanding of the fine physical processes of long continuing current processes.

Estimation of Charge Transfer During Long Continuing Currents in Natural Downward Flashes Using Single‐Station E‐Field Measurements

“…Although according to X. Fan et al (2014), it is not necessarily the case that CCs have their highest magnitude at the beginning of the CC process (which is supported by findings from Campos et al (2007), and Fisher et al (1993)), the segmentation method in this study showed, that, on average, the CCs have a higher magnitude at the beginning, gradually descending toward the end of the process, nearly linear in the case of −CGs. The results showed a median amplitude of −101 A in the first segment and −16 A in the last segment for negative CCs.…”

“…Fan et al. (2014), it is not necessarily the case that CCs have their highest magnitude at the beginning of the CC process (which is supported by findings from Campos et al. (2007), and Fisher et al.…”

A New Method of Three‐Dimensional Location for Low‐Frequency Electric Field Detection Array

“…The detector for changes in the electric field of the LFEDA system uses a traditional fast antenna (Kitagawa & Brook, 1960). Such traditional detection devices can achieve better detection performance and greater data 10.1029/2017JD028249 Journal of Geophysical Research: Atmospheres value through the use of new signal processing and improved algorithms due to the evolving performance of electronic devices and ever-increasing acquisition rates and time accuracy (Fan et al, 2014). These algorithms will improve research on the physics of lightning and thunderstorm electricity.…”

A New Approach of 3D Lightning Location Based on Pearson Correlation Combined with Empirical Mode Decomposition

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