A New Formulation of the Spectral Energy Budget of the Atmosphere, with Application to Two High-Resolution General Circulation Models

摘要: A new formulation of the spectral energy budget kinetic and available potential energies atmosphere is derived, with spherical harmonics as base functions. Compared to previous formulations, there are three main improvements: (i) topography taken into account, (ii) exact three-dimensional advection terms considered, (iii) vertical flux separated from transfer between different harmonics. Using this formulation, results two high-resolution GCMs analyzed: Atmospheric GCM for Earth Simulator (AFES) T639L24 European Centre Medium-Range Weather Forecasts (ECMWF) Integrated Forecast System (IFS) T1279L91. The fluxes show that AFES, which reproduces quite realistic horizontal spectra a k−5/3 inertial range at mesoscales, simulates strong downscale cascade. In contrast, neither vertically integrated nor cascade produced by ECMWF IFS.