Lidar error in complex terrain - case study based on two measurement campaigns

Abstract

Abstract Nowadays, lidar devices are increasingly being used to determine wind potential. The decision to use a lidar device or a meteorological measuring mast depends, among other things, on the topology of the terrain. In flat terrain lidar profilers are sufficiently accurate compared to previously used measuring masts. Due to their measuring principle, however, there are differences in measuring accuracy depending on the terrain. This deviation compared to a measurement with a measuring mast or with anemometers attached to it is referred to as lidar error. However, there are still uncertainties regarding the measurement accuracy of lidar profilers, especially in complex terrain. Among other things, the size of the lidar error in relation to terrain complexity or terrain type is unclear. The lidar error can also differ for different lidar devices with different measuring principles. In order to investigate this in more detail, various lidar devices are compared in this work with regard to their measurement uncertainty in complex terrain. For this purpose, measurement data from two measurement campaigns lasting several months were analyzed. In both measurement campaigns, the lidar devices are compared with data from a measuring mast. There are clear differences between the lidar devices. These are type-dependent, wind speed-dependent and also wind direction-dependent. The latter is due in particular to different terrain topographies from the different cardinal directions. These differences are analyzed with the help of suitable statistical parameters and then evaluated in the context of current scientific research.