UNCERTAINTIES OF THE GRADIENT AND THE VARIANCE METHODS IN RETRIEVING THE MIXING LAYER HEIGHT IN THREE METEOROLOGICAL SCENARIOS

摘要

Mixed layer (ML) heights are extracted from diurnal cycle lidar profiles integrated over different periods of time with a gradient and a variance method in 3 typical meteorological scenarios in Barcelona. In a clean free troposphere (FT), both methods give similar results and depend weakly on integration time. The gradient method gives ML heights with generally lower uncertainty but fails in the case of strong southern advection of Saharan dust (SD). The variance method does not generate any bias in the ML height retrieval but has a rather flat spectrum of errors in the case of SD outbreaks and regional recirculations (RR) of aerosols.