## 2 Materials and Methods
### Introduction of Observation Instruments  
The Windcube 100S Doppler wind lidar is used to observe 3D wind fields in complex terrain. The wind lidar relies on aerosol backscattered laser signals to provide accurate and reliable results [24; 25; 26]. The Windcube 100S is a widely used lidar system for obtaining three-dimensional wind fields at observation sites. It typically uses the Carrier-to-Noise Ratio (CNR) as a key parameter for data quality control. Higher CNR values generally indicate that the signal strength is high relative to the noise, suggesting that the measurements are more reliable and accurate. In contrast, lower CNR values may indicate poorer data quality, which could result from factors such as interference, signal attenuation, or environmental disturbances. Data with CNR values below \(-30\) dBZ are discarded, while data at or above \(-30\) dBZ are considered credible [27; 28]. The adopted CNR threshold of \(-30\) dB is a widely validated metric for ensuring data reliability, as shown in previous studies [29; 30]. The WindCube 100S has a horizontal wind speed accuracy of \(\pm 0.1\) m/s and a wind direction accuracy of \(\pm 2^{\circ}\) under optimal conditions [31]. Regular maintenance and calibration were performed to ensure the accuracy of the data during the observation period. The Windcube 100S with a time resolution of 5 s collects backscattered echo signals from moving particles by emitting laser pulses into the atmosphere, using specific signal processing algorithms to determine the Doppler shift in the backscattered signal and  
Figure 1: The observation locations and major instrument placements used in this study. Panels (**a**,**b**) depict the surrounding terrain of the observation sites, with the red dots indicating the locations of the observation points. Panel (**c**) shows the Windcube 100S Doppler wind lidar (Windcube 100S) (left) and the RPG-HATPRO-G5 microwave radiometer (MWR) (right) placed at the observation sites. analyzing it to calculate radial wind speed and direction along the measurement path. The lidar has a blind spot from the ground to a height of 50 m, and its theoretical maximum detection range is 3 km, limited by signal attenuation. Detailed information about the Windcube 100S and its detection principles can be found in the Supplementary Materials. Detailed information about the Windcube 100S can be acquired from www.leosphere.com (accessed on 4 December 2024). In this study, wind data were averaged to hourly resolution for comparison. The RPG-HATPRO-G5 microwave radiometer (MWR) is a sophisticated instrument designed for continuous, real-time monitoring of the thermodynamic structure of the troposphere, extending from the surface to 10 km in altitude. This advanced system provides a comprehensive set of atmospheric data, including the temperature, absolute and relative humidity, total water vapor content, liquid water path, liquid water profiles, cloud base heights, atmospheric stability indices, and surface meteorological variables such as wind speed and direction. It also includes atmospheric pressure measurements at 2 m above the surface [11; 25; 32; 33; 34]. These parameters are critical for understanding dynamic processes within the boundary layer and the broader atmospheric system, positioning the MWR as an essential tool for both atmospheric research and operational meteorology. The MWR observations exhibit minimal differences when compared to radiosonde data, demonstrating its suitability for boundary layer studies [35]. It provides reliable data for vertical structure analyses by offering temperature and humidity profiles from the surface up to 10 km. The MWR operates with a high temporal resolution of 1 s, enabling continuous, near-real-time observations. The RPG-HATPRO-G5 MWR is designed to provide high-precision atmospheric measurements. According to the manufacturer's technical note, the instrument achieves a temperature profile accuracy of approximately 0.25 K RMS in the lower atmosphere (0-500 m) and up to 1 K RMS in higher altitudes (up to 10 km).