Transient and stationary spectra of kinetic energy (*KE*), available potential energy (*APE*) and enstrophy (*EN*), and their spectral fluxes as a function of the two-dimensional wavenumber*n* were computed for July 1979. Triangular truncation at zonal wavenumber 42 was used for computation. The slopes of various spectra in the wavenumber range 14≤*n*≤25 were obtained by fitting a straight line in log-log scale by the least square method. The transient*KE, APE* and*EN* spectra in the lower (upper) troposphere had slopes −2·21 (−2·30), −2·65 (−2·64) and −0·36 (−0·46), respectively. The effect of stationary and divergent motion on the slope values was investigated. The possible correlation between the slope and percentage of transient component in the combined energy and enstrophy was examined to identify the transient motion of the atmosphere with the two-dimensional homogeneous isotropic turbulence. The vertically averaged slope of kinetic energy and enstrophy in the lower (upper) troposphere was close to the value at 700 (200) hPa level.

The spectral fluxes of kinetic energy and enstrophy in the wavenumber range 14≤*n*≤25 satisfied, to a very rough approximation, the criteria of inertial subrange. The stationary fluxes were small. The estimated stationary-transient component of flux was larger, comparable and less than the corresponding transient flux of APE, KE and EN.

Representative levels for computation of energy and enstrophy spectra and their fluxes in the lower and upper troposphere were identified.