[A-AS08] Processes of the Moist Atmosphere Across Scales

[AAS08-P01] The relationship between lightning characteristics and cloud characteristics derived from ground-based electric field measurements.

★Invited Papers

*Naota Iwai¹, Yousuke Sato², Mitsuteru Sato², Masaru Inatsu², Atsushi Nagao³, Yumiko Yamashita³, Toshihisa Masuda³, Takashi Ikeda³, Makoto Hosoda⁴, Norihito Hirasawa⁴ (1.Graduate School of Science, Hokkaido University, 2.Faculty of Science, Hokkaido University, 3.NTT Space Environment and Energy Laboratories, 4.NTT EAST Corporation)

Keywords:lightning, electric field measurement, neutralized charge amount

This study estimated the three-dimensional location of lightning and the neutralized charge amount of lightning from ground-based electric field measurement data. To achieve this, we installed field mill sensors at four sites in Gunma, Japan during the summer of 2023, and a point charge model [1][2] was applied to estimate the lightning location and the neutralized charge amounts. Based on the estimated lightning location and the neutralized charge amount, as well as results of analyses of meteorological radar and weather charts, we examined the relationship between the neutralized charge amount and the characteristics of convective clouds accompanying lightning. To examine this, we applied the classification by Ogura et al. (2002) [3][4] and Taguchi et al. (2002) [5]. The analyses revealed that lightning associated with convective clouds triggered by synoptic-scale disturbances exhibited higher lightning frequency and larger neutralized charge amounts. In contrast, lightning associated with convective clouds produced by smaller-scale disturbances tended to have lower lightning frequency and smaller neutralized charge amounts. These results suggest that the characteristics and formation mechanisms of convective clouds affect both lightning occurrence frequency and neutralized charge amounts.

[1]Jacobson E. A., and Krider E. P., 1976: Electrostatic field changes produced by Florida lightning. J. Atmos. Sci. 33(1), 103-117, doi:10.1175/1520-0469(1976)033.
[2]Krehbiel P. R., Brook M., and McCrory, R. A., 1979: An analysis of the charge structure of lightning discharges to ground. J. Geophys. Res. 84(C5), 2432-2456, doi:10.1029/JC084iC05p02432.
[3]Ogura Y., K. Okuyama, and A. Taguchi, 2002: The thunderstorm activity observed by SAFIR and its relation to the atmospheric environment over the Kanto area in the summer. Part 1: An overview of the thunderstorm activity and thunderstorm generating mechanisms. Tenki. 49(7), 541-553.
[4]Ogura Y., K. Okuyama, and A. Taguchi, 2002: The thunderstorm activity observed by SAFIR and its relation to the atmospheric environment over the Kanto area in the summer. Part 3: Effects of upper-level disturbances on the thunderstorm generation. Tenki, 49(9), 747-762.
[5]Taguchi A., K. Okuyama, and Y. Ogura, 2002: The thunderstorm activity observed by SAFIR and its relation to the atmospheric environment over the Kanto area in the summer. Part 2: Thunderstorm prediction by stability indices. Tenki, 49(8), 649-659.