Evaluation and Correction of Doppler Lidar–Derived Turbulent Kinetic Energy for Urban Air Mobility Applications

Turbulent kinetic energy (TKE) is a fundamental parameter for characterizing atmospheric turbulence and is essential for assessing hazardous weather conditions that directly impact Urban Air Mobility (UAM) operations. Accurate estimation of turbulence intensity is particularly important for ensuring the safety and efficiency of low-altitude urban airspace, where UAM vehicles operate under complex and highly variable atmospheric conditions. While three-dimensional sonic anemometers are widely regarded as the reference standard for TKE estimation due to their high temporal resolution and accuracy, their measurements are inherently limited in spatial representativeness, especially in heterogeneous urban environments.

Doppler lidar has emerged as a promising remote sensing technology capable of providing spatially distributed wind and turbulence information over extended areas, making it highly suitable for operational applications in UAM. In this study, TKE estimates derived from Doppler lidar are systematically compared with those obtained from three-dimensional sonic anemometers collocated on a 300 m meteorological tower. The analysis reveals that lidar-derived TKE is consistently higher than that measured by the sonic anemometer.

To investigate the underlying causes of this discrepancy, several potential error sources are examined, including volume averaging effects associated with the lidar measurement volume, instrumental noise, limitations in scanning strategies, and assumptions involved in retrieving velocity variances. Furthermore, multiple correction techniques are explored to enhance the reliability of lidar-based TKE estimates, such as noise filtering, spectral correction methods, and adjustments accounting for spatial averaging effects. The performance of these correction approaches is quantitatively evaluated through direct comparison with reference measurements from the sonic anemometer.

The findings of this study improve the accuracy of Doppler lidar–derived turbulence measurements and support the development of reliable hazardous weather information systems for conditions such as turbulence, wind shear, and crosswind. Ultimately, this research provides a robust scientific foundation for real-time turbulence monitoring and contributes to safer and more efficient UAM operations in complex urban environments.