UPRM Boundary Layer Data Improvements Implementing Variable Overlap Correction

Jose F. Nieves and Hamed Parsiani


boundary layer, elastic-inelastic, backscatter coefficient improvement


At the UPRM Atmospheric Research Laboratory, the backscatter-power data received from the Lidar equipment is processed and used to construct a power profile. The Lidar has a transmit/receive capability for the basic wavelengths of 355, 532, and 1064 nm. Recently, it has been expanded to provide Raman scattering power data at 387nm, and 407nm, the later being improved for signal to noise ratio enhancement. The power profiles are then used to determine various atmospheric parameters, including the fundamental aerosol backscatter coefficient. The overlap factor in a co-axial Lidar system is responsible for the inability of the telescope to focus the backscatter data originated at the lower altitudes, hence, it will influence any product derived from this data. The method applied (Ansmann 2002) to determine the corrected-overlap profile of the UPRM Lidar equipment is based on the received Raman inelastic (387nm) and elastic (355nm) backscatter signals. It is an iterative approach that makes use of the fact that the deviation between the Klett's solution for the backscatter coefficient, which is calculated from the elastic backscatter signal, and the Raman Lidar solution, contains the information about the overlap factor. As a result, the determination of the overlap factor will improve backscatter power data at the lower altitudes and provide a more accurate boundary layer detection. In this paper, the backscatter power correction has been applied to the Lidar three received wavelengths.

Important Links:

Go Back