Comparisons of Doppler Lidar Wind Measurements using VAD Analysis

In the past decade, Doppler lidars have been used in an increasing number of applications and research projects. As such, it is important to verify that measurements coming from these instruments are accurate and reliable. Additionally, operators must know what scanning strategy should be used under varying conditions to collect the high quality data in the quickest time possible. To verify Doppler lidar wind measurements, data collected using the velocity-azimuth display (VAD) scanning technique are analyzed and compared with observations from a sonic anemometer on a 60 m tower, UHF radar wind profiler, and rawinsondes at the DOE Atmospheric Radiation Measurement Southern Great Plains site during the spring and summer months of 2012. Additionally, a Halo Stream Line scanning lidar, which was recently acquired by the University of Oklahoma (OU) and is nearly identical to the lidar used at the ARM site, has been deployed at OU's Kessler Atmospheric and Ecological Field Station (KAEFS) in central Oklahoma near the OU campus. During the summer of 2012, sequential VAD scans at varying elevation angles were conducted with the lidar to determine the effect of the elevation angle on the retrieved wind profile. The number of azimuths required for an accurate measurement of the wind has also been investigated. Additionally, comparisons between the OU lidar, a sodar, and unmanned aerial system were possible at KAEFS.