An improved method for automatic determination of the planetary boundary layer height based on lidar data

The planetary boundary layer height (PBLH) is a primary parameter characterizing the boundary layer and its accurate estimation is critical. The wavelet covariance transform method is a common inversion algorithm of the PBLH estimation, but is subject to the problems of dilation selection and interference from clouds, aerosols, etc. An improved method combining the whale optimization algorithm (WOA) and the top limit (TL) is proposed to overcome these difficulties and realize the automatic determination of PBLH. In particular, the dilation obtained by WOA can be more accurate, to several decimal places, compared to the frequently-used empirical integers. The proposed method is tested on different simulation and real cases, and compared with radiosonde measurements. The results show that the improved method is accurate, effective and stable for automatic retrieval of PBLH based only on simple micropulse lidar (MPL), without the aid of other measurements. (C) 2020 Elsevier Ltd. All rights reserved.