| Aerosol spatial and temporal distribution is an important issue in atmospheric science research,which directly affects the changes of thermal radiation,atmospheric stability.convection,turbulence and clouds;Aerosol mass concentration spatial and temporal distribution usually reflects the regional air quality and pollution level,which is a hot spot of concern for the public and government.Remote sensing technology is an important means to realize the detection of aerosol spatial and temporal distribution,and how to realize the quantitative and high spatial and temporal resolution remote sensing of aerosol mass concentration is an urgent problem to be solved.As an active remote sensing instrument,lidar has the characteristics of long detection distance and high spatial resolution,which can realize the effective detection of aerosol spatial and temporal distribution in vertical and horizontal directions.This dissertation aims at the quantitative and high-precision remote sensing detection of aerosol mass concentration distribution,and uses lidar as the detection means to carry out the research on the detection method,inversion algorithm and experimental observation technology of aerosol mass concentration distribution,which has important theoretical significance and application value.A parameterized model between aerosol optical properties and mass concentration is established.The visibility data and PM1,PM2.5 and PM10 mass concentration data of Xi’an in the past two years obtained via the ground base visibility meter and wide range aerosol particle size spectrometer(WRAS).The relationships between optical characteristics and mass concentration under different weather conditions are studied,and the expression of the relationship between them is obtained by using the nonlinear least square method,and the exponential mass concentration equation is established;The correlation between aerosol mass concentration and meteorological elements is analyzed by Combining temperature and humidity data from meteorological stations,the influence of relative humidity on the parameterized model is studied,the mechanism of relative humidity on the growth of aerosol hygroscopicity is revealed,and a detection method for aerosol mass concentration that can be adapted to different relative humidity ranges is formed.The method of aerosol mass concentration profile detected by Raman scattering lidar is proposed,the inversion method of PM1,PM2.5 and PM10 mass concentration profile and its uncertainty calculation method are constructed,the applicability conditions and application scope of the method are studied,and the calibration experiment of the method is completed.The results of the inversion of PM1,PM2.5 and PM10 mass concentration profiles by Raman scattering lidar with different wavelengths and the causes of errors were studied.The experimental results validate the correctness of the proposed method.The data inversion algorithm of aerosol optical properties based on the scattering ratio Parameterized calibration method is proposed,and the inversion method of multi-wavelength Mie scattering lidar is investigated for the problems of fast signal-to-noise ratio decay and strong interference from background light in daytime when using Raman scattering lidar system.The correlations between the aerosol backscattering ratio at 355nm and 532nm and 1064nm wavelengths are given,and the method of scattering ratio parameterized calibration for Fernald backward integration algorithm is constructed.The problem of simultaneous inversion of multi-wavelength aerosol optical properties profiles are solved,and the inversion accuracy and precision are improved.The detection experiment of aerosol mass concentration level distribution is completed,and the detection results show that the detection of aerosol mass concentration distribution can be effectively realized by using Mie scattering lidar.A method for detecting aerosol mass concentration by near-infrared high spectral resolution lidar(N-HSRL)is proposed,and a fine inversion algorithm of aerosol optical properties based on the threshold correction method is constructed.The influence of the spectral transmittance of aerosol and molecular scattering signals on the inversion results of aerosol optical properties in the Fabry-Perot standard(FPE)channel,a high spectral resolution filtering element in N-HSRL,is investigated.The problem of data distortion caused by derivation in retrieving aerosol extinction coefficient profile is solved.The N-HSRL system platform has been established,the aerosol optical properties profiles can be finely detected by 1064 nm N-HSRL,and the PM1,PM2.5 and PM10 mass concentration profiles are obtained successfully. |
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