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[1] Previous papers by Franke et al. (2011) and Fritts et al. (2011) described the computation of radar backscatter power and vertical velocities from numerical simulations of turbulence arising due to Kelvin-Helmholtz (KH) shear instability. Comparisons of backscatter power and inferred velocities with the distributions of turbulence and the true velocities revealed biases in the identification of active or intense turbulence and in the inferred Doppler spectrum and vertical velocities throughout the flow evolution. This paper extends these analyses to off-zenith viewing angles typical of multiple-beam MF, HF, and VHF radars. These reveal similar biases in the identification of turbulence occurrence, Doppler spectra, and inferred radial velocities, with additional sensitivity to the off-zenith angle relative to the mean shear across the turbulence layer. Radial velocities are typically underestimated during turbulence generation and breakdown of the KH billows, except where turbulence refractive index gradients are strong. Doppler spectra are biased toward regions retaining strong refractive index gradients, implying strong aspect sensitivity at later stages in the evolution. Persistent tilted structures at late stages of the evolution contribute to radial velocity measurement biases that also are functions of off-zenith angle and time.

[1] An outstanding question about the dynamics of the mesosphere is the temporal and spatial distribution of nonlinear events such as wave-breaking, wave saturation, and wave-critical layer interactions. A climatology of these events will help us understand how the mesoscale dynamical features, such as gravity waves, interact with the background mean wind and temperature structure. New lidar systems have the resolution to show us a height versus time ''picture'' of the dynamics so that identifying individual events within the observation window of the instrument is now possible. At the Starfire Optical Range (SOR) a sodium resonance lidar provides simulataneous sodium density, temperature, and three components of the winds. In this paper we present ''pictures'' of individual wave events apparent in the lidar data using the temperature (plotted as potential temperature and spectra) to show the time evolution of the wave structure.

Multiple‐receiver MF radar returns from the mesosphere are used to investigate the relationship between spaced antenna (SA), radar interferometry (RI), and imaging Doppler interferometry (IDI) wind estimation techniques. Our results show that frequency‐domain (RI and IDI) and time‐domain (SA) techniques yield almost identical results under high SNR conditions suitable for SA full correlation analysis (FCA).