Development of a small portable eyesafe unattended scanning lidar for analysis of the structural and optical properties of tropospheric aerosols

Structural and optical properties of aerosols and clouds can be retrieved by active remote sensing systems, such as lidars. Such parameters are of importance in the study of dynamics and radiation budget of the atmosphere. In that respect, a small, portable, eyesafe, unattended, elastic-backscatter lidar is being developed at Cimel Electronique, in collaboration with CNRS. It sues a compact, low-energy laser in the visible. The detection is made by a high-gain, high-speed PMT, and a single electronic card for fast acquisition. The aim of the system is also to be tunable to various pointing angles. A variational method was developed to make use of the multiangle measurements and tested on data collected during the INDOEX campaign in March 1999. The optical thickness and backscatter coefficient profiles were retrieved up to 1 km with a total uncertainty of 18 percent. The system has been assembled and first measurements have been made beginning of 2000 for comparison with the theoretical predictions. The system has shown it was satisfactory and the signal profiles obtained are in agreement with the ones simulated with the system parameters.