Research On Inversion Of PM_2.5 Mass Concentration In Guilin Based On CE-318 Data

Guilin is a famous tourist city and international tourism integrated transportation hub in the world.And while it has become an important link between The Belt and Road and Guangdong,Guangxi,Hunan and Guizhou in recent years,Guilin economy has entered a stage of rapid development.The air quality in Guilin has grown worse year by year and more and more people pay attention and attach importance to the atmosphere pollution and air quality condition of Guilin.Atmosphere aerosol made up of suspension of liquid and solid particles with diameter ranges from 0.001 to 100?m in the atmosphere which has a greater influence on atmosphere pollution,and has become a research hotspot on atmospheric environmental issues.Therefore,it has important significance to provide scientific basis for the monitoring and control of urban air pollution by studying the Atmosphere aerosol in Guilin.The data which the paper uses includes the observation data from ground-based monitoring stations and CE-318 multi waveband sun photometer in Guilin from September2017 to August 2018.The paper studies atmospheric aerosol optical properties and analyzes and models the correlation between AOD and PM_2.5 mass concentration for by statistical analysis method and regression modeling,in order to achieve the purpose of remote sensing inversion of PM_2.5 mass concentration.The main research results are as follows:1?With different wavelength bands,atmospheric aerosol extinction characteristics are different,and AOD decreases when the wavelength increases.The seasonal variation of AOD in Guilin changes to spring>winter>autumn>summer.Because the average annual value of?is 1.265,so fine particles are the main particles of atmospheric aerosol in Guilin,and the atmospheric aerosol type of Guilin is the mixture of the Industry-urban aerosol and the maritime aerosol.The PWV vapor content has obvious seasonality and its changing trend is consistent with the climate characteristics of Guilin.Visibility changes to summer>autumn>winter>spring,and is inversely related to AOD.2?PM_2.5 and PM₁₀ are the primary air pollutants in Guilin.PM_2.5 mass concentration is more correlated with AOD than PM₁₀.The correlation between AOD and PM_2.5 mass concentration is enhanced with decreasing wavelength.3?AOD and PM_2.5 mass concentration five kinds of function type regression modeling results for autumn and summer optimal fitting model is a power function model,the fitting equation and R of autumn are y=72.175x^0.8157,R=0.75,and the fitting equation and R of summer are y=41.925x^0.6221,R=0.804.The best fitting model for winter and spring is a one-dimensional quadratic function model,the fitting equation and R of winter are y=-29.93x²+118.11x+10,R=0.755,the fitting equation and R of spring are y=-6.2 x²+38.617x+11.7,R=0.653.The correlation between AOD and PM_2.5 mass concentration is the strongest in summer,followed by winter and autumn,and weakest in spring.4?The relative humidity in the four seasons has the greatest impact on estimating the mass concentration of PM_2.5 in autumn,followed by spring.The PM_2.5 remote sensing estimation model based on AOD and relative humidity is better than the remote sensing estimation model based on AOD.