Diurnal Dynamics of Standard Deviations of Three Wind Velocity Components in the Atmospheric Boundary Layer

Diurnal dynamics of the standard deviation (SD) of three wind velocity components measured with a minisodar in the atmospheric boundary layer is analyzed. Statistical analysis of measurement data demonstrates that the SDs for x- and y-components sigma(x) and sigma(y) lie in the range from 0.2 to 4 m/s, and sigma(z) = 0.1-1.2 m/s. The increase of sigma(x) and sigma(y) with the altitude is described sufficiently well by a power law with exponent changing from 0.22 to 1.3 depending on time of day, and sigma(z) increases by a linear law. Approximation constants are determined and errors of their application are estimated. It is found that the maximal diurnal spread of SD values is 56% for sigma(x) and sigma(y) and 94% for sigma(z). The established physical laws and the obtained approximation constants allow the diurnal dynamics of the SDs for three wind velocity components in the atmospheric boundary layer to be determined and can be recommended for application in models of the atmospheric boundary layer.