Reply on CC1

Abstract

Reliable simulation of wind patterns that form under stable weather conditions is vital to prevent air pollution. Here, we investigated how different physical parameterization schemes impact surface wind simulations over the coastal regions of North China using the Weather Research and Forecasting (WRF) model with a horizontal resolution of 0.5 km. We performed 640 ensemble simulations using multiple combinations of 10 planetary boundary layer (PBL), 16 microphysics (MP), and four longwave/shortwave (LW/SW) radiation schemes. Model performance was evaluated using measurements from weather station observations. These data show that WRF model can reproduce the temporal variation of wind speed and direction to a high degree of accuracy. The simulated wind speed is most sensitive to the PBL schemes, followed by LW/SW radiation schemes and MP schemes, while wind direction is less sensitive to variation of the physical parameterizations. Among all PBL schemes, the MYJ scheme shows the strongest correlation with observation data, while the YSU scheme had the smallest model bias. A combined Dudhia and RRTM scheme and MYDM7 scheme show the best model performances out of all LW/SW radiation and MP schemes, respectively. Our results show that the interactions among physical components also play an important role in wind simulations. Further investigations indicate that land type has a profound influence on model sensitivity. For example, for the weather stations located in coastal regions. The MYNN scheme showed the highest correlation among all PBL schemes, while LES and YSU has the smallest model errors, the RRTMG and Goddard schemes showed the highest correlations and smallest biases out of all LW/SW radiation schemes. Our results indicate the roles that various parameterization schemes play in wind simulations under stable weather conditions, and provide a valuable reference for further research in this region and in other locations around the world.