Investigation of Secondary Gravity Wave Variability using a 3-Field-of-View Doppler-Rayleigh Lidar in Kühlungsborn, Germany

Abstract

Recent interpretations of atmospheric gravity wave propagation have emphasized the importance of secondary and higher-order gravity waves.  One implication of multi-stage vertical coupling of gravity waves could be an increased probability of measuring larger vertical wavelengths than would be expected from a primary gravity wave.  These secondary waves are also expected to be intermittent in time and localized in space, which means that lidars are an excellent technique for detecting these phenomena.  We present lidar gravity wave measurements from temperatures and winds using a zenith pointing beam and two 25-degree off-zenith beams. In each lidar field-of-view, gravity wave energy is estimated as a function of vertical wavelength and period using a Morlet wavelet analysis.  This analysis is conducted at multiple altitudes in each of the three beams to determine small-scale horizontal variability, which could indicate small-scale wave activity associated with primary wave breaking.