Variabilité de la densité spectrale de la température et du vent moyen dans la couche limite planétaire

We have carried out a series of recordings reproducing the small scale structures of temperature and windspeed within the boundary layer. The results obtained have been processed by computer and a direct comparison made between the slope of the spectral density functions and the theoretical slopen=5/3 defining the turbulence in the region of the inertial subrange.The measurements made at various altitudes on thin atmospheric samples demonstrate the variability of the spectral density slope with altitude. The hypotheses put forward by A. M. Obukhov, R. Bolgiano, G. H. Shur, P. Misme, A. Monin or S. Panchev, for example, enable the spectral variations and certain discontinuities in the turbulence observed during the experiments, within and beyond the boundary layer, to be explained.