Accurate Jovian Radio Flux Density Measurements Show Ammonia to be Subsaturated in the Upper Troposphere

The availability of new accurate radio flux densities of Jupiter in and around the λ1.3 cm ammonia absorption band, one from groundbased radio data and five from the WMAP satellite, permits reexamination of the structure of the Jovian upper troposphere. These flux densities, with accuracies of 1–3%, indicate that the Jovian atmospheric ammonia is globally subsaturated within and above the ammonia cloud tops, 0.4 bar ≤ P ≤ 0.6 bar, and subsolar (by a factor of 2) below the cloud base, 0.6 bar ≤ P ≤ 2 bar.