[M-IS19] Atmospheric electricity and application of technology for reducing disaster risks

[MIS19-P02] Development of lightning discharges prediction algorithm using characteristics of precipitation particles and radar parameters

Atsuya Yamachi¹, *Hiroshi Kikuchi¹, Eiichi Yoshikawa^2,3, Yoshitaka Nakamura⁴, Takeshi Morimoto⁵, Tomoo Ushio⁶ (1.The University of Electro Communications, 2.Japan Aerospace Exploration Agency, 3.Colorado State University, 4.Kobe City College of Technology, 5.Kindai University, 6.Osaka University)

Keywords:Lightning discharge prediction, phased-array radar

The rapid development of cumulonimbus clouds in a short period of time causes unpredictable weather disasters, and heavy rains and lightning strikes can have a major impact on society, such as power outages and traffic disruptions, so forecasting is extremely important. In recent years, research institutes around the world have been working on the development of phased arrays of meteorological radar. In Japan, a single polarization phased array radar was developed in 2012, and a dual polarization phased array radar (MP-PAWR) was developed in 2018. MP-PAWR succeeded in reducing the time resolution of 3D observations to less than 30 seconds. At the same time, MP-PAWR enabled high-density observations within the Kanto area. Our research group has also been conducting lightning observations in the Kanto area since 2020 using a 3-D lightning targeting device that uses the LF band. In a previous study, a method for predicting the location of lightning strikes using radar reflection factors was proposed, but it had the problem that it showed excessive lightning risk prediction for the entire rain cloud and was a prediction algorithm limited to aircraft lightning [1].
In this study, we investigated the relationship between the spatially dense distribution of precipitation particles using MP-PAWR and discharge propagation paths using a low frequency (LF) band 3D lightning marker, and developed an algorithm to predict the location of lightning strikes in summer cumulus clouds based on this relationship.