Variable winds on Venus mapped in three dimensions
Hueso, R ; Piccioni, G ; Drossart, P ; et al. ; - ASI Sponsor
Jan - 2007
DOI: 1O.1029/

journal : GEOPHYSICAL RESEARCH LETTERS
type: Article Journal

Abstract
Two fundamentally different circulation regimes separated at latitudes 55°have been found to operate on 4 Venus, using cloud observations from the VIRTIS imaging spectrometer on Venus Express. At low latitudes, 6 zonal winds in the Southern hemisphere at altitudes ranging from 47 to 66 km are nearly constant with latitude 8 with westward velocities of 105 m/s at cloud-tops and 9 60-70 m/s at the cloud-base. At high latitudes, zonal IO wind speeds decrease Iinearly with virtually no vertical Il wind shear, indicating a verticalIy coherent vortex struc- 12 ture. Meridional winds at the c1oud-tops are poleward 13 with peak speed of lO m/s at 55°S but are found to be 14 light below the cloud tops. We a1s0 report the detection 15 at subpolar latitudes of variable winds due to the salar 16 tide and to a 5 days oscillation.

keywords : VENUS EXPRESS