Linear Approximations of Turbulent Moments of Horizontal Velocity and Temperature Fluctuations Within a Forced Convection Sublayer of the Atmospheric Surface Layer

In the convective surface layer a heavy forced convection sublayer is distinguished. The turbulent moments of this sublayer depend mainly on the buoyance flux. It is shown that "linear" approximations are effective for describing turbulent moments of this sublayer. These approximations correspond to truncated Taylor series expansions in a modified height, that include only two terms. The first-order expansion terms do not take into account the wind and represent the free convection limits of the Monin-Obukhov similarity theory. The second-order expansion terms take into account the wind and its effect on the convection. The proposed approximations are compared with the experimental data.