Vol. 10, issue 03, article # 12

pdf Banakh V. A., Werner Ch., Kopp F., Smalikho I. N. Fluctuation spectra of wind velocity measured with a Doppler lidar. // Atmospheric and oceanic optics. 1997. V. 10. No. 03. P. 202-208.
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Abstract:

This paper presents some results of theoretical and experimental study of the temporal spectra of fluctuations of wind velocity measured with a cw Doppler lidar. It is shown, that the temporal spectrum of wind velocity measured with a Doppler lidar essentially differs from the Kolmogorov-Obukhov’s spectrum which describes turbulence of wind velocity measured at a fixed point due to low-frequency spatial filtration of wind velocity fluctuations over scattering volume. In particular, it is revealed, that when the lidar scattering volume is large and sufficiently strong side wind takes place, so that the Taylor’s hypothesis of “frozen” turbulence is applicable within the probing volume, the lidar spectrum has a power frequency dependence with the power index “-8/3” but not “-5/3” as it takes place in point measurements. When the Taylor’s hypothesis is not applicable, the lidar spectra have a power frequency dependence with power index approximately “-2”.