[A-CG38] Dynamics of Oceanic and Atmospheric Waves, Vortices, and Circulations

[ACG38-P01] Akatsuki LIR observing system simulation experiments in the Venus atmosphere

*Norihiko Sugimoto^1,2, Yukiko Fujisawa², Nobumasa Komori², Hiroki Ando³, Toru Kouyama⁴, Masahiro Takagi³ (1.Keio University, Department of Physics, 2.Keio University, Research and Education Center for Natural Sciences, 3.Kyoto Sangyo University, Faculty of Science, 4.National Institute of Advanced Industrial Science and Technology, Digital Architecture Research Center)

Keywords:Venus atmosphere, Akatsuki, Data assimilation, Longwave Infrared Camera, Thermal tide

Impacts of temperature assimilation on the Venus atmosphere are investigated by the observing system simulation experiments assuming Akatsuki Longwave Infrared Camera (LIR) observations. Synthetic temperature observations are produced by a Venus general circulation model (VGCM) and assimilated at 70 km altitude with several combinations of frequency and horizontal region. The three-dimensional structure of thermal tides is significantly improved, even if observations are available only at a limited frequency of 6-hourly or on the dayside. The zonal–mean zonal wind and temperature fields are also modified at 60–80 km altitudes globally through the vertical momentum transport of thermal tides. Therefore, assimilation of Akatsuki LIR observations to produce realistic objective analysis of the Venus atmosphere would be promising.

Sugimoto, N. et al., Akatsuki LIR observing system simulation experiments evaluated by thermal tides in the Venus atmosphere, Geoscience Letters, Vol.9, (2022), 44, https://doi.org/10.1186/s40562-022-00253-8.