[A-AS07] Analyses and Prediction of Extreme Weather and Climate in Southeast Asia

[AAS07-P05] Estimating the lightning charge amount and height basis on the semi-electrostatic field in Manila

*由井 祥¹、高橋 幸弘¹、佐藤 光輝¹、久保田 尚之¹、菅野 将史 (1.北海道大学)

Every year, torrential rains brought by cumulonimbus clouds cause a lot of damage, especially in Southeast Asia. Therefore, improving the accuracy of heavy rainfall prediction has become an urgent social issue. in 1982, Piepgrass et al. found that the frequency of lightning discharges changes about 5 minutes before heavy rain (Piepgrass et al., 1982). This suggests that detailed observations of lightning discharges can be used to make short time predictions of heavy rainfall. In this study, the source of lightning discharges can be determined in three dimensions by observing the changes in the electric field caused by lightning discharges and fitting them using the least-squares method. This makes it possible to estimate the interior of a cumulonimbus cloud from the ground. Although field mills are generally used to observe electric field changes in cumulonimbus clouds, this research uses a plate-type capacitance antenna, which is inexpensive and suitable for high-density observation at multiple locations. In a previous study, Kanno established a method for estimating lightning discharge sources in clouds and calibrating the relative sensitivity using a plate-type capacitance antenna, and analyzed the results on 2020/07/11 07:06-07:15 UT (Kanno, 2021). In this study, we extended the analysis period and discussed the inside of cumulus clouds and the relationship between precipitation and lightning discharges. As a result of the analysis, the average starting height of lightning discharges remained relatively unchanged throughout the entire period, and most of them were distributed between about 6,000 m and 12,000 m altitude. I also discussed the relationship between the temporal changes in these 3D positions and precipitation.This research was supported by Science and Technology Research Partnership for
Sustainable Development (SATREPS), Japan Science and Technology Agency
(JST) / Japan International Cooperation Agency (JICA).