Unravel the extent of the existence of positive ground flash in Malaysia

Abstract

Positive cloud-to-ground flash (+CG) in tropic countries such as Malaysia is not common. However, some studies in Malaysia reported that the +CG in Malaysia occur more than the nominal percentage of 10 %. The uncertainty feature as mentioned above motivates the authors to stratify the +CG from 135 electric field data acquired in two different thunderstorms recorded in Melaka, Malaysia. To ensure consistency of the measurement, the accurate stroke count technique that widely have been used by majority lightning investigators was utilized in Universiti Teknikal Malaysia Melaka measurement station. The electric fields were recorded with nanosecond resolution using High Definition Lecroy. The signal of lightning study within few Hz to tens of MHz, were detected by the combination of parallel plate antenna and voltage follower amplifier. In summary, negative cloud to ground flashes (-CG), +CG and cloud flash (CC) were found to have 123(91%), 6 (4.44%) and 6 (4.44%), respectively. Further, comparison study has shown that there is no consistency in previous studies in Malaysia and Indonesia and lead to uncertainty. Overall, it is extremely important to all researchers in tropical region to realize that the positive lightning has to be scrutinized carefully and still open into a big question in presenting a proper manner.