Abstract The mesosphere and lower thermosphere (MLT) region plays a crucial role in the vertical coupling between the lower and upper atmosphere, but continuous regional observations of its wind field remain rare. In this study, we utilize observations from the Eastern China Multistatic Meteor Radar Network (ECMMET) to evaluate two 3‐dimensional wind retrieval methods: the newly developed Volume Velocity Processing (VVP) (NDVVP) and the 3‐dimensional variational assimilation using the divergence constraint (3DVAR+DIV). Both methods maintain stable performance at temporal resolutions as high as 10 min and yield highly consistent horizontal winds, with mean wind correlation coefficients exceeding 0.9 and wind velocity mean differences within 1 m/s. Comparisons with simultaneous lidar observations further confirm the reliability of the ECMMET‐derived winds, particularly the 3DVAR regional winds, which exhibit a correlation coefficient of 0.93 and a root‐mean‐square (RMS) difference of 14.0 m/s relative to the lidar observations at 88 km. The results showed that the 3DVAR+DIV method effectively reveals more detailed spatial variability, whereas the NDVVP performs better for retrieving the overall trend of the wind field. The non‐random discrepancies between the two retrievals originate from their inherent assumptions. NDVVP's linear wind assumption smooths higher‐order and nonlinear fluctuations, while 3DVAR+DIV captures them more effectively through spatial gridding. These findings emphasize the advantages of both methods and demonstrate ECMMET's capability to provide reliable, high‐resolution, and refined wind measurements essential for studies of MLT dynamics.
Zeng et al. (Mon,) studied this question.