Global Structure of Thermal Tides in the Upper Cloud Layer of Venus Revealed by LIR on Board Akatsuki

T. Kouyama, M. Taguchi, T. Fukuhara, T. Imamura, T. Horinouchi, T. M. Sato, S. Murakami, Joji Hashimoto, Y. J. Lee, M. Futaguchi, T. Yamada, M. Akiba, T. Satoh, M. Nakamura

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Longwave Infrared Camera (LIR) on board Akatsuki first revealed the global structure of the thermal tides in the upper cloud layer of Venus. The data were acquired over three Venusian years, and the analysis was done over the areas from the equator to the midlatitudes in both hemispheres and over the whole local time. Thermal tides at two vertical levels were analyzed by comparing data at two different emission angles. Dynamical wave modes consisting of tides were identified; the diurnal tide consisted mainly of Rossby-wave and gravity-wave modes, while the semidiurnal tide predominantly consisted of a gravity-wave mode. The revealed vertical structures were roughly consistent with the above wave modes, but some discrepancy remained if the waves were supposed to be monochromatic. In turn, the heating profile that excites the tidal waves can be constrained to match this discrepancy, which would greatly advance the understanding of the Venusian atmosphere.

Original languageEnglish
JournalGeophysical Research Letters
DOIs
Publication statusAccepted/In press - Jan 1 2019

    Fingerprint

Keywords

  • Akatsuki
  • LIR
  • thermal tides
  • Venus

ASJC Scopus subject areas

  • Geophysics
  • Earth and Planetary Sciences(all)

Cite this

Kouyama, T., Taguchi, M., Fukuhara, T., Imamura, T., Horinouchi, T., Sato, T. M., Murakami, S., Hashimoto, J., Lee, Y. J., Futaguchi, M., Yamada, T., Akiba, M., Satoh, T., & Nakamura, M. (Accepted/In press). Global Structure of Thermal Tides in the Upper Cloud Layer of Venus Revealed by LIR on Board Akatsuki. Geophysical Research Letters. https://doi.org/10.1029/2019GL083820