The structural function of entropy and turbulence scales

Structure functions of sound speed and local entropy in the turbulent atmosphere are analyzed. By long-term measurements in the atmospheric boundary layer the power dependence of these characteristics in the inertial sub-range is significantly diverged from the “2/3 law”. Behavior of structure functions indicates deviation from the asymptotic Kolmogorov-Obukhov law on scales, which significantly exceed Taylor microscale. The exponent of 2/3 is regarded as the limit value, which can be reached under different synoptic conditions. Analytical expressions for the internal and “energy” scales of entropy fluctuations, as well as for relation of these scales with entropy dissipation rate and energy of adiabatic fluctuations are proposed.