Analysis of temporal dynamics of the standard deviation of three wind velocity components from the data of acoustic sounding

Abstract

In the report the spatiotemporal dynamics of standard deviation of three wind velocity components measured with a minisodar in the atmosphere boundary layer is analyzed. During 5-day measurements, the variance changed for the x - and y -components of the wind velocity from 1 to 12 m/s, and for the z -component from 0.2 to 0.4 m/s in the morning hours and in the evening from 2 to 10 m/s for the x - and y -components and from 0.6 to 0.9 m/s for the z -component. An analysis of the vertical profiles of the standard deviations of the three wind velocity components demonstrates that the increase of σ x and σ y with altitude is well described by a power-law dependence with the exponent changing from 0.22 to 1.3 depending on time of a day, and σ z increases by a linear law. Approximation constants are found and errors of their application are estimated. The established physical regularities and the approximation constants obtained allow the diurnal dynamics to be described and can be recommended for application in the ABL models.