Can Wind Lidars Be Used to Calibrate Mean Wind Profiles?

This paper explores to which extent Wind Lidars can be used to calibrate mean wind profiles, also in relation to the characteristics of the available measurements. Starting from measured wind speeds in the range 50 m to 250 m from the ground obtained in a LIDAR experimental campaign, pseudo-experimental wind speed profiles are generated by adding a zero-mean Gaussian noise to the logarithmic law; this is representative of realistic measurement errors. Then, a least-square fitting procedure is applied to identify the roughness length and the zero-plane displacement. The procedure is applied to two different mean wind profiles, corresponding to densely built areas featuring mid-rise and low-rise buildings, respectively. The results show increasing scatter in the identified parameters of the log-law with increasing height of the lowest measurement point and with decreasing number of measurement points. This suggests that to improve accuracy of the identified profile at low heights, an additional point of measurement is needed, lower than those allowed by available LIDAR technology, or that a very large number of measured profiles must be available.