Jovian large-scale stratospheric circulation

We infer Jupiter's stratospheric mean meridional residual circulation by balancing annual-average radiative net heating/cooling with adiabatic cooling/heating associated with vertical motions. Voyager 1 IRIS observations were used to define the thermal structure in the pressure range 0.3 to 270 mbar. Aerosol radiative heating plays an important role. Several independent observations indicate aerosols to be concentrated at high latitudes in the region near and just below the 1-mbar altitude. Voyager 2 photopolarimeter ultraviolet data also indicate a distinct north/south asymmetry in radiative heating which is not balanced by radiative cooling. A prominent feature of these models is a two-cell structure centered near the 10-mbar level, with subsidence occurring at the equator, and upwelling at high latitudes. This large-scale circulation did not appear in previous work (Conrath et al. 1990, Icarus 83, 255-281) in which aerosol heating was neglected. At the base of the stratosphere, where there is no aerosol heating in our model, we confirm the meridional circulation pattern proposed by Gierasch et al. (1986, Icarus 67, 456-483), with upwelling over zones and subsidence in belt regions. The magnitude of the upwelling/subsidence is a factor of 2 more vigorous than that proposed by Gierasch et al. Our model also estimates the seasonally averaged Eliassen-Palm flux divergence. This quantity is small at low latitudes and reaches extreme values, both positive and negative, in the latitude ranges 80 S to 40 S and 30 N to 80 N. At these latitudes it is most strongly negative near the 230-mbar level and most strongly positive near the 5-mbar level. Gravity waves propagating from the deeper atmosphere seem to be the most likely mechanism responsible for this pattern of eddy forcing.