Abstract

We present distributions of the zonal-mean temperature and static stability in the Venusian atmosphere obtained from Venus Express and Akatsuki radio occultation profiles penetrating down to an altitude of 40?km. At latitudes equatorward of 75°, static stability derived from the observed temperature profiles is consistent with previous in-situ measurements in that there is a low-stability layer at altitudes of 50?58?km and highly and moderately stratified layers above 58?km and below 50?km, respectively. Meanwhile, at latitudes poleward of 75°, a low-stability layer extends down to 42?km, which has been unreported in analyses of previous measurements. The deep low-stability layer in the polar region cannot be explained by vertical convection in the middle/lower cloud layer, and the present result thus introduces new constraints on the dynamics of the sub-cloud atmosphere. The Venusian atmosphere is in striking contrast to the Earth’s troposphere, which generally has a deeper low-stability layer at low latitudes than at mid- and high latitudes.

Paper

Title: Thermal structure of the Venusian atmosphere from the sub-cloud region to the mesosphere as observed by radio occultation

Publication: Scientific Reports 

Author: Hiroki Ando*, Takeshi Imamura, Silvia Tellmann, Martin Patzold, Bernd Hausler, Norihiko Sugimoto, Masahiro Takagi, Hideo Sagawa, Sanjay Limaye, Yoshihisa Matsuda, Raj Kumar Choudhary & Maria Antonita 

DOI: 10.1038/s41598-020-59278-8

Date: 26 February 2020