Simulation performance of different planetary boundary layer schemes in WRF V4.3.1 on wind field over Sichuan Basin within "Gray zone" resolution

Abstract. The topography of Sichuan Basin is complex and unique, high-resolution wind field simulation over this region is of great significance for meteorology, air quality, and wind energy utilization. In this study, Weather Research and Forecasting (WRF) model was used to investigate the performance of different planetary boundary layer (PBL) parameterization schemes on simulating surface wind fields over Sichuan Basin at a spatial resolution of 0.33 km. The experiment is based on multi-case studies, so 28 near-surface wind events from 2021 to 2022 were selected, and a total of 112 sensitivity simulations were carried out by employing four commonly used PBL schemes: YSU, MYJ, MYNN2, and QNSE, and compared to observations. The results show that the wind direction which can be well reproduced, is not very sensitive to the PBL schemes as the wind speed shows. As for wind speed, the QNSE scheme had the best performance in reproducing the temporal variation out of the four schemes, while the MYJ scheme had the smallest model bias. Further cluster analysis demonstrates that the sensitivity of the PBL schemes is affected by diurnal variation and different circulation genesis. For instance, when the surface wind event caused by the southward movement of strong cold air and occurred during 6:00 and 8:00 (UTC), the variation and speed can be well reproduced by all four PBL schemes and the differences between them are tiny. However, the simulation of surface wind events mostly occurred during midnight and early morning, showing the characteristics of poor RMSE and good COR, while the simulation results of the evening-to-evening process and southerly wind process were opposite. Overall, the four schemes are better for surface wind simulations in daytime than at night. The results show the role of PBL schemes in wind field simulation under unstable weather conditions, and provide a valuable reference for further research in the study area and surrounding areas.