[P-EM13] Coupling Processes in the Atmosphere-Ionosphere System

[PEM13-P18] ICON satellite observations of thermospheric winds

*Yusuke Ioka¹ (1.Department of Earth and Planetary Sciences, Graduate School of Science, Kyushu University)

ICON is a NASA scientific satellite launched in 2019, which observes wind speeds at altitudes between 90 and 300 km using the Michelson interferometer. In this study, we used these observations to extract the diurnal and semidiurnal components of the atmospheric tides and investigate their seasonal variations. The results show that the diurnal tide is stronger above 200 km, while the semidiurnal tide is more pronounced around 100 km. At 250 km, the diurnal tide is stronger in spring and autumn, and the semidiurnal tide is weaker in spring and autumn. 100 km, the diurnal cycle is stronger in spring and summer, and weaker in autumn and winter. At 100 km, the diurnal period is stronger in spring and summer and weaker in autumn and winter, and the semidiurnal period is weaker in spring and winter and stronger in summer and autumn.
In addition, the ICON and CHAMP satellite observations at 350 km height are compared. The amplitude of the diurnal tide is larger at 350 km altitude (~100 m/s) than at 250 km altitude (~100 m/s), and the amplitude of the semidiurnal tide is similar at both altitudes (15-20 m/s), although there is no significant difference in the time of maximum wind speed.