A Garrett-Munk-type spectrum, describing in the frequency-wave number space the energy per unit mass distribution of the atmospheric buoyancy wave field, is derived from experimental spectra of the field variables, within the following constraints: (1) the spectral modeling must refer to kz spectra, in order to minimize the spectral contributions of the possibly coexisting quasi-two-dimensional turbulence and; (2) the resulting model must correspond to a saturated wave field in its high wave number limit. A spectral dependence on intrinsic frequencies is estimated from the ratios of experimental temperature and vertial velocity kz spectra, obtained by balloon-borne instrumentation. These results and previously published horizontal velocity kz spectra allow determination of the model spectrum parameters, which differ substantially from those proposed by VanZandt (1982). This resulting model spectrum is characterized by a nearly universal high wave number liit (with a -3 spectral slope) and a total energy that varies, mainly with altitude. Two typical atmospheric conditions, characterized by high or low vertical velocity variances, are, however, much better represented using two slightly different parameter sets. Then, the model spectra account for most experimental mesoscale range kz, kH, and frequency presence or absence of a turbulent buoyancy subrange, while, in both cases, the energy levels within the saturated subrange imply strongly interacting wave fields. ¿ American Geophysical Union 1988