An axisymmetric model is developed to study the climate equilibrium of a hydrostatic tropical atmosphere. Its main features are the inclusion of an explicit hydrological cycle and the NCAR column radiation model, the same one used in CCM3. In addition, the model employs primitive equations in spherical coordinates, and a convective adjustment is currently used to represent the effects of tropical convection. Meridional heat fluxes to midlatitudes are not allowed due to the presence of lateral boundaries at the equator and at 30 degrees N. Given the standard choice of input parameters, steady-state conditions are achieved in about 400 model days. Some qualitative attributes of the zonally averaged tropical circulation -- surface easterlies/westerlies and the Hadley cell -- compare favorably with previous studies. Moreover, the magnitude of the upper level jet is more realistically simulated when contrasted to other symmetric models in published literature. Following the pattern of the calculated thermally direct circulation, the troposphere is mostly saturated in the rising branch region close to the equator. Conversely, the region dominated by sinking motion produces a dry upper-troposphere. Since this study employs the so-called inverse climate simulation method, the sea-surface temperature is used as a surrogate for climate change. Preliminary results show that the model climate sensitivity lies within the typical range of equatorial sensitivities given by coupled global models. Thus, the simple model can be used to establish a cause and effect relationship that might be partially suggestive of the CGCMs' results