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The height of the mixing layer is a significant parameter for describing the dynamics of the planetary boundary layer (PBL), especially for air quality control and for the parametrizations in numerical modeling. The problem is that the heights of the mixing layer cannot be measured directly. The values of this parameter are depending both on the applied algorithms for calculation and on the measuring instruments which have been used by the data source. To determine the height of a layer of intense turbulent heat exchange, data were used from acoustic meteorological locator (sodar) and from a passive single-channel scanning microwave radiometer MTP-5 (MWR) to measure the temperature profile in a layer of up to 1 km. Sodar can provide information on the structure of temperature turbulence in the PBL directly. These data have been compared with the mixing layer height calculated with the Parcel method by using the MTP-5 data. For the analysis, July and September 2020 were selected in the city of Tomsk in Siberia as characteristic periods of mid-summer and the transition period to autumn. The measurement results, calculations and inter-comparisons are shown and discussed in this work. During temperature inversions in the boundary layer, it was observed that turbulent heat transfer (increased dispersion of air temperature) is covering the inversion layers and the overlying ones. Moreover, this phenomenon is not only occurring during the morning destruction of inversions, but also in the process of their formation and development.

The statistical analysis of contributions from different combinations of pulsations of air temperature and vertical component of the wind to the turbulent heat flux (quadrant analysis) has been performed with the values of these components measured by ultrasonic meteostations (sonic) in the atmospheric surface layer at different sites, different height, and in different time in the summer season.

The report presents estimates of the interlevel correlation of the wind velocity components from the data of acoustic sensing of the atmospheric boundary layer under different atmospheric conditions. The correlation matrices whose components are correlation moments for different altitude levels are analyzed. The influence of omissions in the initial data arrays on the statistical robustness of estimates of the examined functions is discussed.