Automatic determination of the planetary boundary layer height using lidar: One‐year analysis over southeastern Spain

Abstract

[1] The planetary boundary layer (PBL) height is a key variable in climate modeling and has an enormous influence on air pollution. A method based on the wavelet covariance transform (WCT) applied to lidar data is tested in this paper as an automated and nonsupervised method to obtain the PBL height. The parcel and the Richardson number methods applied to radiosounding data and the parcel method applied to microwave radiometer temperature profiles are used as independent measurements of the PBL height in order to optimize the parameters required for its detection using the WCT method under different atmospheric conditions. This optimization allows for a one-year statistical analysis of the PBL height at midday over Granada (southeastern Spain) from lidar data. The PBL height showed a seasonal cycle, with higher values in summer and spring while lower values were found in winter and autumn. The annual mean was 1.7 AE 0.5 km a.s.l. during the study period. The relationship of the PBL height with aerosol properties is also analyzed for the one-year period.Citation: Granados-Muñoz, M. J., F. Navas-Guzmán, J. A. Bravo-Aranda, J. L. Guerrero-Rascado, H. Lyamani, J. Fernández-Gálvez, and L. Alados-Arboledas (2012), Automatic determination of the planetary boundary layer height using lidar: One-year analysis over southeastern Spain,

Study of mineral dust entrainment in the planetary boundary layer by lidar depolarisation technique

“…This method is applied only during daytime since results are not reliable under non-convective conditions. The PBL height uncertainty is around 200 and 400 m above and below 2 km, respectively, due to the aforementioned different resolution of the temperature profile derived by the microwave radiometer (Granados-Mun˜oz et al, 2012).…”

“…Tropospheric profiles were obtained from the surface up to 10 km using 39 heights with vertical resolution ranging from 10 m near the surface to 1 km for altitudes higher than 7 km agl. 25 independent points with vertical resolution between 10 and 200 m are provided below 3 km agl, where the PBL is usually located over Granada (Granados-Mun˜oz et al, 2012). Temperature profiles were used to determine the PBL height using the parcel method (Holzworth, 1964;Granados-Mun˜oz et al, 2012;Wang et al, 2012;Cimini et al, 2013;Corredor-Ardoy et al, 2014) and to calculate the potential temperature in combination with the vertical profiles of pressure of the 1976 Standard Atmosphere (Krueger and Minzner, 1976) scaled at surface pressure.…”

A Method for Deriving the Boundary Layer Mixing Height from MODIS Atmospheric Profile Data

“…The Richardson number Rib is defined as [1]: (1) where g is the gravity acceleration, z0 is the altitude of the measurement location above sea level, θ is the potential temperature, and μ(z) and v(z) the wind zonal and meridional components, respectively. The MH is defined as the height where the Richardson number equals the critical Richardson number of 0.21 [17,18]. At heights where Rib is higher than the critical value, the atmosphere is considered to be free of turbulence (free troposphere).…”

An Improved Iterative Fitting Method to Estimate Nocturnal Residual Layer Height

“…The entrainment layer at the top of the boundary layer exerts a partial blocking effect on the dispersion of surface pollutants; this effect results in a high concentration of near-surface contaminants [4][5][6]. Therefore, accurate determination of PBL height is significant for weather forecasting and studying air quality and climate [7,8].…”

“…Continuous elastic Lidar measurement with high spatial and temporal resolution allows for the estimation of the diurnal cycle of RLH [4,10,11]. Three Lidar methods used to obtain RLH are the ideal profile-fitting (IPF) [12], gradient (Grad) [5,8,13], and wavelet covariance transform (WCT) methods [10,14,15].…”