Influence of Venus topography on the zonal wind and albedo at cloud top level : The role of stationary gravity waves

Jean-Loup Bertaux (1) , Emmanuel Marcq (1) , Igor V. Khatunstsev (2) , Wojciech J. Markiewicz (3) , Alain Hauchecorne (4) , Sébastien Lebonnois (5) , Marina Patsaeva (2) , Alexander Turin (2) , Anna Fedorova (2)

1 PLANETO - LATMOS
2 IKI - Space Research Institute of the Russian Academy of Sciences
3 MPS - Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research
4 STRATO - LATMOS
5 LMD - Laboratoire de Météorologie Dynamique (UMR 8539)

Based on the analysis of UV images (at 365 nm) of Venus cloud top (altitude 67±2 km) collected with VMC (Venus Monitoring Camera) on board Venus Express (VEX), it is found that the zonal wind speed south of the equator (from 5°S to 15°s) shows a con- spicuous variation (from -101 to -83 m/s) with geo- graphic longitude of Venus, correlated with the un- derlying relief of Aphrodite Terra. We interpret this pattern [1] as the result of stationary gravity waves produced at ground level by the up lift of air when the horizontal wind encounters a mountain slope. These waves can propagate up to cloud top level, break there and transfer their momentum to the zonal flow.

Domaines: Planétologie et astrophysique de la terre [astro-ph.EP]; Astrophysique stellaire et solaire [astro-ph.SR]

Jean-Loup Bertaux, Emmanuel Marcq, Igor V. Khatunstsev, Wojciech J. Markiewicz, Alain Hauchecorne, et al.. Influence of Venus topography on the zonal wind and albedo at cloud top level : The role of stationary gravity waves. International Venus Conference 2016, Apr 2016, Oxford, United Kingdom. ⟨insu-01298368⟩