Seasonal and diurnal variability of planetary boundary layer height in Beijing: Intercomparison between MPL and WRF results

• Published in: Atmospheric research Vol. 227; pp. 1 - 13
• Main Authors: Chu, Yiqi, Li, Jing, Li, Chengcai, Tan, Wangshu, Su, Tianning, Li, Jian
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2019
• Subjects: Diurnal variation; Micropulse LIDAR; PBL scheme; PBLH; PBL scheme; PBLH; Diurnal variation; Micropulse LIDAR
• ISSN: 0169-8095; 1873-2895
• DOI: 10.1016/j.atmosres.2019.04.017

The Planetary boundary layer (PBL) plays an important role in energy exchange and pollutant dispersion. The height of the PBL (PBLH) usually exhibits distinct diurnal variation. In this study, we investigate the characteristics of PBLH variation of Beijing China based on 1-year observations from Micropulse LIDAR (MPL) data, and compared against the PBLH simulated by the Weather Research and Forecast (WRF) model using eight different schemes. The variation of daytime MPL PBLH has been classified into four representative types using k-means clustering technique. Through comparison against MPL, it is shown that the Mellor-Yamada Nakanishi and Niino Level 3 (MYNN3) scheme, a second-order closure scheme, performs the best in representing the PBLH variation in most of the cases. The non-local schemes also show advantages in convective situations, due to the stronger vertical mixing embedded in these schemes. Further analyses show that differences in PBLH definition is a major factor causing the divergence among different schemes, while the biases of the profiles play a minor role. •Four different types of PBLH diurnal variation in Beijing are classified and analyzed.•Second-order scheme performs the best in simulating the boundary layer height especially under stable weather conditions.•The 1.5-theta-increase method performs better than many other definitions of PBLH.•Definition of the PBLH can cause significant divergence in the results of different schemes.