SRS-lidar for environmental monitoring atmospheric surface layers

Abstract

Background: The development and implementation of new methods of environmental monitoring is an urgent problem due to the technogenic pollution of the Earth's biosphere. The remote control of the gas composition of the surface atmosphere layer in industrial zones of modern metropolis is important for determining penalties for enterprises whose emissions of pollutants exceed established norms. Objectives: Development of an ecological Spontaneous Raman Scattering (SRS) lidar for monitoring the gas composition in the air basin of large megacities. Theoretical verification of the lidar effectiveness for problem solving. Materials and methods: The developed lidar for environmental monitoring of the atmospheric surface layer is based on the SRS method which allows remote monitoring of the atmospheric gas composition at distances up to several kilometers with a fairly high resolution (up to 1 meter). The absolute concentration of detected polluting gases is determined by comparing the intensities of the satellite pollutant and nitrogen lines in the recorded SRS spectra. Results: The choice of the SRS method for remote laser monitoring of the atmosphere ground layer in large industrial centers is substantiated. The block diagram and the main technical characteristics of the developed SRS lidar are presented. Preliminary estimates of the lidar efficiency for the environmental monitoring were carried out. Conclusions: The simulation results have shown that the specifications of the SRS lidar allow detecting of following polluting gases: CO, NO2, SO2, CH4, H2S, C6H6 at distances up to 200 m with the maximum permissible concentration level. The simulation results were obtained when accumulation time varied from 10 s to 4 min. The specification of the SRS lidar allow its using for remote monitoring of air conditions in the cities and near industrial enterprises.