Located at the base of the troposphere and affected strongly by ground surface,the planetary bounda-ry layer (PBL)is the main passage of air-land interaction and air pollution.The PBL affects the momen-tum and heat exchange between the ground and atmosphere through the surface force and turbulence trans-port.The concentration of pollutants on the ground depends on the vertical mixing state of the atmos-phere.Thus,the boundary layer parameterization scheme is not only the important part of numerical mod-el for weather forecast,but also the important foundation of air pollution numerical model.A variety of boundary layer parameterization schemes of physical process are developed,which have different effects on the ground meteorological field and pollutant diffusion.To further understand how the boundary layer processes affect the mixing and transport of air pollutants,a sensitivity experiment is designed and the WRF-Chem model with different PBL schemes (MYJ,YSU and ACM2 )is utilized to simulate the PBL structures and O3 vertical distributions on a cloudless and steady day (26 -27 Aug 2013).Simulations of temperature field and wind speed field using different PBL schemes are compared to observations.The a-nalysis focuses on the difference of simulations of residual layer formation at night and O3 vertical distribu-tion after sunrise using different PBL schemes.Simulations are compared with the radiosonde data of ozone at Gucheng Station.Results show that the regional distribution characteristics and vertical structures of the temperature and wind speed can be well simulated by all these three PBL parameterization schemes, but the simulation of the ground temperature and wind speed are generally on the high side.The nighttime boundary layer height simulated by MYJ scheme is much higher than those simulated by YSU and ACM2 schemes,leading to the difference in near surface pollutants concentration.In the evolution process of the boundary layer structure from stable state in nighttime to slightly disturbance state after sunrise,the verti-cal temperature and wind structures simulated by YSU and ACM2 schemes are more consistent with obser-vations.Simulations on effects of boundary layer process upon O3 vertical distribution using YSU and ACM2 schemes also have obvious advantages over MYJ scheme.It should be noted that the simulation is only on a clear and steady weather case,and for complex weather conditions,effects of boundary layer schemes need further verification.%利用 WRF-Chem 模式，采用3种边界层参数化方案（YSU，MYJ 和 ACM2），针对1个晴空、静稳日（2013年8月26日20：00—27日20：00（北京时））进行模拟，着重分析不同边界层参数化方案对夜间残留层形成及日出前后O3浓度垂直分布形式的模拟效果，并与固城站地面及垂直同步观测资料进行对比。结果表明：3种边界层参数化方案均能够模拟出温度及风速的区域分布形式以及风温垂直结构的变化特征；相比之下，MYJ 方案模拟的夜间边界层高度较 YSU 方案和 ACM2方案明显偏高，该对比结果可能是导致近地面污染物浓度模拟差异的重要原因；在夜间稳定层结至日出后稳定状态打破的边界层结构演变过程中，采用 YSU 方案和 ACM2方案模拟的温度和风速垂直扩线形式与观测结果更为接近；同样采用非局地闭合的 YSU 方案和同时考虑局地和非局地闭合的 ACM2方案，对于边界层高度内 O3浓度垂直分布形式的模拟效果具有明显优势。
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