[P-EM12] Coupling Processes in the Atmosphere-Ionosphere System

[PEM12-P29] Classification of Ionograms in the Polar region by the Vertical Incidence Pulsed Ionospheric Radar at Jang Bogo Station, Antarctica

*Junho Back^1,2、Geonhwa Jee^2,3、Hyuck-Jin Kwon²、Khan-Hyuk Kim¹、Changsup Lee^2,3、Young-Bae Ham^2,3 (1.School of Space Research, Kyung Hee University、2.Division of Atmospheric Sciences, Korea Polar Resarch Institue、3.Department of Polar Scienc, Korea University of Science and Technology)

キーワード：Ionogram

The electron density profile of an ionogram is traditionally estimated using image processing techniques based on the shape of echoes reflected in the ionosphere. Vertical Incidence Pulsed Radar (VIPIR) with Dynasonde, however, uses a 3-D inversion program named NeXtYZ, which estimates the electron density profile through phase analysis of reflected echoes. In this study, we automatically classified ionograms obtained from VIPIR/Dynasonde installed at Jang Bogo Station (JVD) for a 5-year period from 2017 to 2021 to validate the efficiency of the NeXtYZ program. We found that more than 50% of ionograms show a reasonable electron density profile. However, NeXtYZ did not properly calculate electron density profiles under dynamic structures of the polar ionosphere, such as sporadic-E and aurora. The distribution of good profiles depends on magnetic local time and season, which may be attributed to the effects of solar irradiation and electric fields at high latitudes. In future work, we will investigate the reasons behind the frequent occurrence of Es layers during the winter seasons and in the dawn and dusk sectors.