Three-dimensional structure of thermal waves in Venus’ mesosphere from ground-based observations

• Published in: Icarus (New York, N.Y. 1962) Vol. 387; p. 115187
• Main Authors: Giles, Rohini S., Greathouse, Thomas K., Irwin, Patrick G.J., Encrenaz, Thérèse, Brecht, Amanda S.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 15.11.2022
• Subjects: Atmospheres, structure; Infrared observations; Spectroscopy; Venus, atmosphere; Spectroscopy; Atmospheres, structure; Venus, atmosphere; Infrared observations
• ISSN: 0019-1035; 1090-2643
• DOI: 10.1016/j.icarus.2022.115187

High spectral resolution observations of Venus were obtained with the TEXES instrument at NASA’s Infrared Telescope Facility. These observations focus on a CO2 absorption feature at 791.4 cm-1 as the shape of this absorption feature can be used to retrieve the vertical temperature profile in Venus’ mesosphere. By scan-mapping the planet, we are able to build up three-dimensional temperature maps of Venus’ atmosphere, covering one Earth-facing hemisphere and an altitude range of 60–83 km. A temperature map from February 12, 2019 clearly shows the three-dimensional structure of a planetary-scale thermal wave. This wave pattern appears strongest in the mid-latitudes of Venus, has a zonal wavenumber of 2–4 and the wave fronts tilt eastward with altitude at an angle of 8–15 degrees per km. This is consistent with a thermal tide propagating upwards from Venus’ upper cloud decks. Ground-based observations provide the opportunity to study Venus’ temperature structure on an ongoing basis. •Ground-based observations were used to map Venus’ three-dimensional thermal structure.•A temperature offset map from February 2019 shows a planetary-scale wave.•The wave pattern is consistent with an upward propagating thermal tide.