Atmospheric electric field measurement advances in Southern peninsular Malaysia

Lightning, which is also known as electrical charge separation in atmosphere, performs energetic discharge. By monitoring the atmospheric electric field (AEF), it helps to give precaution against the risk of lightning. The rotating electric field mill (REFM) is a sensor used in measuring AEF. REFM comprises of signal processing circuit (consists of amplification unit, filtering, conversion, and signal conditioning unit) for connection to data acquisition equipment in order to display, collect, and analyse the data. An investigation of different materials on REFM rotor and stator was performed to reveal their sensitivity and stability towards the high voltage atmosphere. The calibration results showed that aluminium sensor had been more suitable for AEF measurement compared to stainless steel sensor. The research purpose was to track the thundercloud development processes and movement. In addition, in order to investigate the characteristics of the signal from a thunderstorm cloud prior to cloud ground lightning discharges, the REFM was installed in UTM area. The data collected on-site revealed the characteristic signals of AEF in the atmosphere and the characteristics of the signal from a thunderstorm cloud prior to CG lightning discharges.