A Comparative Study on the Positive Lightning Return Stroke Electric Fields in Different Meteorological Conditions

Abstract

Positive cloud-ground lightning is considerably more complex and less studied compared to the negative lightning. This paper aims to measure and characterize the significant parameters of positive return strokes electric field, namely, the zero-to-peak rise time, 10–90% rise time, slow front duration, fast transition rise time (10–90%), zero-crossing time, and opposite polarity overshoot relative to peak. To the best of the authors’ knowledge, this is the first time such detailed characteristics of positive lightning in Malaysia are thoroughly analyzed. A total of 41 positive lightning flashes containing 48 return strokes were analyzed. The average multiplicity is 1.2 strokes per flash. The majority of positive lightning was initiated from the primary positive charge rather than as a byproduct of in-cloud discharges. The cumulative probability distribution of rise time parameters, opposite polarity overshoot relative to peak, and slow front amplitude relative to peak are presented. A comparison between studies in four countries representing tropic, subtropic, and temperate regions was also carried out. Measured parameters in Florida, Sweden, and Japan are generally lower than those in Malaysia. Positive lightning occurrences in tropical regions should be further studied and analyzed to improve our current understanding on positive return strokes.

Characteristic of preliminary breakdown preceding negative return stroke in Malaysia

“…2 and 3 show the samples of waveforms with recorded flash number fitting the BIL and BL models, respectively. This study is similar with that described in [13] where 79% of measurements taken in December 2012 have PBPs, but is different from [14] where 46% of the flashes taken April-June, 2009 have PBPs.…”

“…1. The setup is similar to experimental setups used in [4,5,13,14]. The vertical component of electric field was captured using a 1.5m-height parallel plate antenna.…”

Statistical Analysis on Preliminary Breakdown Pulses of Positive Cloud-to-Ground Lightning in Malaysia

“…Despite the fact that many counties already reported the PBP preceding positive return stroke [4,6,16,21,22], apart from our own study reported in [23], this is the first time preliminary breakdown preceding positive lightning in Malaysia is reported. The initial polarity of PBP in negative cloud-to-ground (-CG) lightning is always the same as that of the first return stroke.…”

Statistical Analysis on Preliminary Breakdown Pulses of Positive Cloud-to-Ground Lightning in Malaysia

“…As summarized by [20], such percentage apparently varies with latitude. The smallest percentage is 19%, Despite the fact that many counties already reported the PBP preceding positive return stroke [4,6,16,21,22], apart from our own study reported in [23], this is the first time preliminary breakdown preceding positive lightning in Malaysia is reported. The initial polarity of PBP in negative cloud-to-ground (-CG) lightning is always the same as that of the first return stroke.…”