The vertical structure of Jupiter's equatorial zonal wind above the cloud deck, derived using mesoscale gravity waves

摘要

Data from the Galileo Probe, collected during its descent into Jupiter'satmosphere, is used to obtain a vertical profile of the zonal wind from$\mathbf{\sim 0.5}$ bar (upper troposphere) to $\mathbf{\sim 0.1\, \mu{bar}}$(lower thermosphere) at the probe entry site. This is accomplished byconstructing a map of gravity wave Lomb-Scargle periodograms as a function ofaltitude. The profile obtained from the map indicates that the wind speed abovethe visible cloud deck increases with height to $\mathbf{\sim 150}$m\,s$\mathbf{^{-1}}$ and then levels off at this value over a broad altituderange. The location of the turbopause, as a region of wide wave spectrum, isalso identified from the map. In addition, a cross-equatorial oscillation of ajet, which has previously been linked to the quasi-quadrennial oscillation inthe stratosphere, is suggested by the profile.