PBL and dust layer seasonal evolution by lidar and radiosounding measurements over a peninsular site

Planetary boundary layer (PBL) and dust layer (DL) height evolution have systematically been investigated during the past 2 years at Lecce, Italy (40.33°N, 18.10°E) using a lidar. These heights are identified as the height at which the first and second measurable minima of the derivative of the lidar signal normalized to the backscatter molecular signal occurs. The PBL and DL heights were lower during the summer than the winter, contrary to what is expected. This behavior can be explained in terms of the suppression of the boundary layer depth growth caused by the advection of marine air. It is shown that PBL and DL heights retrieved by lidar are in good agreement with the ones obtained by radiosounding measurements from a close meteorological station.