The method of radial velocities (RV) is applied to estimate aircraft wake vortex parameters from measurements conducted with pulsed coherent Doppler lidar (PCDL). Operations of the Stream Line lidar and the 2-µm PCDL are simulated numerically to analyze the accuracy of the estimated wake vortex parameters with the RV method. The RV method is also used to estimate wake vortex trajectories and circulation from lidar measurements at Tomsk and Munich airports. The method of velocity envelopes and the RV method are compared employing data gathered with the 2-µm PCDL. The domain of applicability of the RV method is determined.

The kinetic energy of turbulence, the dissipation rate of turbulent energy, and the integral scale of turbulence in the stable atmospheric boundary layer at the location heights of low-level jets (LLJs) have been measured with a coherent Doppler light detection and ranging (lidar) system. The turbulence is shown to be weak in the central part of LLJs. The kinetic energy of turbulence at the maximum velocity heights of the jet does not exceed 0.1 (m/s)², while the dissipation rate is about 10⁻⁵ m²/s³. On average, the integral scale of turbulence in the central part of the jet is about 100 m, which is two to three times less than the effective vertical size of the LLJ.

A strategy of measurement by a 1.5-μm pulsed coherent Doppler lidar “Stream Line” has been developed, and a method for estimation of aircraft wake vortices from the lidar data has been proposed. The principal possibility of obtaining the information about the vortex situation over an airport airfield with the Stream-Line lidar has been demonstrated.

The strategy providing an estimation of both the mean velocity and the temporal and spatial spectra of radial velocity from data of the same pulse coherent Doppler lidar is proposed. Theoretical relations taking into account the averaging over the probing volume while estimating the spectra of fluctuations of the radial velocity measured by lidar are presented. The method of estimation of the turbulent energy dissipation rate and the variance of the vertical component of wind velocity vector from the spectra of radial velocity is carried out. The results of the comparative experiments are discussed and used in further studies of wind turbulence in the atmospheric boundary layer during the formation of low-level jets and propagation of internal gravity waves.

The results of a theoretical and experimental study of the feasibility of the turbulent energy dissipation rate ϵ_T measurements with a continuous wave (CW) CO₂ Doppler lidar in the atmospheric boundary layer are presented. Three methods of probing ϵ_T are considered: 1) Doppler spectrum width, 2) the temporal spectrum (temporal structure function) of wind velocity measured by the Doppler lidar, and 3) spatial structure function. In these methods, information on the dissipation rate is extracted by means of analysis of the corresponding statistical characteristics of wind velocity in the inertial subrange of the turbulence, taking into account the spatial averaging of the measured wind velocity fluctuations over sounded volume. In the first and third methods, the spatial structure of the turbulence is analyzed directly. In the second method, to determine ϵ_T from the measured temporal characteristics, it is necessary to use a model for the spatiotemporal correlation function of wind velocity. As a result of the study, it has been shown that in the case of large longitudinal size of sounded volume and weak side wind, Taylor’s hypothesis of “frozen” turbulence cannot be accepted for the correlation function. The strict limitation on the longitudinal size of the sounded volume and therefore sounding height is the main restriction of the first method. The third method is free of such limitations. It allows one to obtain the information on the dissipation rate profile throughout the entire boundary layer. Comparison of the developed theory for statistical characteristics of wind velocity measured by the Doppler lidar with the obtained experimental data has demonstrated their good agreement. The vertical profiles of the turbulent energy dissipation rate retrieved from Doppler lidar data with the use of the methods described above do not contradict the known experimental results. This fact confirms the feasibility of application of lidar remote sensing methods to the study of the small-scale turbulence in the atmospheric boundary layer.

The paper presents the results of probing the stable atmospheric boundary layer in the coastal zone of Lake Baikal with a coherent Doppler wind lidar and a microwave temperature profiler. Two-dimensional height–temporal distributions of the wind velocity vector components, temperature, and parameters characterizing atmospheric stability and wind turbulence were obtained. The parameters of the low-level jets and the atmospheric waves arising in the stable boundary layer were determined. It was shown that the stable atmospheric boundary layer has an inhomogeneous fine scale layered structure characterized by strong variations of the Richardson number Ri. Layers with large Richardson numbers alternate with layers where Ri is less than the critical value of the Richardson number Ri_cr = 0.25. The channels of decreased stability, where the conditions are close to neutral stratification 0 < Ri < 0.25, arise in the zone of the low-level jets. The wind turbulence in the central part of the observed jets, where Ri > Ri_cr, is weak, increases considerably to the periphery of jets, at heights where Ri < Ri_cr. The turbulence may intensify at the appearance of internal atmospheric waves.