Application of Three-Dimensional Boundary Layer Schemes in Wind Field Simulation under Complex Terrain of the Tibetan Plateau

The Tibetan Plateau is renowned for its complex topography and heterogeneous surface, which lead to uneven surface heating and, consequently, trigger various local circulation phenomena such as valley winds, glacier winds, and lake-land breezes. To more accurately capture these unique meteorological conditions and improve wind field simulations in complex terrain, this study introduced and compared six different boundary layer parameterization schemes to evaluate their performance in simulating the wind field in the regions of the Lake Nam Co and Mount Everest. The study utilized two three-dimensional boundary layer schemes: SMS-3DTKE and PBL3D; two variations of SMS-3DTKE—one with simplified horizontal diffusion (3DTKE_smag) and another with the horizontal diffusion term completely removed (3DTKE_0); and two traditional one-dimensional boundary layer schemes: MYNN and Shin-Hong. Observed data was used to validate the simulation results. The results indicated that the two three-dimensional boundary layer schemes provided wind profiles at the Qomolangma Atmospheric and Environmental Observation and Research Station, CAS (QOMS) that closely matched observations, significantly outperforming the one-dimensional schemes. In particular, the three-dimensional schemes not only successfully simulated the near-surface wind field and the wind characteristics at 500 meters, but also explained the mechanism behind the afternoon strong winds—caused by the convergence of westerly winds crossing the ridge and southwesterly winds in the Rongbuk Valley. Furthermore, the SMS-3DTKE scheme excelled in simulating the onset time and intensity of the lake breezes at the Nam Co Monitoring and Research Station for Multisphere Interactions, CAS (NAMORS), underscoring the importance of incorporating horizontal diffusion terms in local circulation simulations. These findings are crucial for improving wind field simulation accuracy under complex terrain conditions using three-dimensional boundary layer schemes and provide valuable insights for future research.