Sounding of Kelvin-Helmholtz waves by a turbulent lidar. II. Lidar BSE-5
I.A. Razenkov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: turbulent lidar, backscatter enhancement effect, Kelvin-Helmholtz instability, atmospheric turbulence
Abstract
In continuation of the first part of the work, experimental results of Kelvin-Helmholtz wave sounding with an UV BSE-5 lidar (355 nm), with the sensitivity higher than that of BSE-4 lidar (532 nm), are presented. Experiments on atmospheric sounding with the BSE-5 lidar were carried out in the winter-spring period over a built-up area, which is a “heat island". Improved lidar parameters in combination with thermal conditions in the atmospheric boundary layer, which is mainly stable stratified in the cold season, enables us to acquire new data on the shape of Kelvin-Helmholtz waves. It is ascertained that echo signals in both receiving channels of the lidar decrease by 30% after a sounding laser beam passes a turbulence intensity peak at the top of the wave arc. This effect of the atmosphere on echo signals of the turbulent lidar can be explained by beam broadening due to multiple scattering on random inhomogeneities of the medium.
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