Research On The Estimation Of PM_2.5 Mass Concentration With The Quantitative Remote Sensing In Jangsu Province

Recently,with the rapid industrial development and expanding urbanization the air pollution problems have become more serious,which impacted on human living environment.The most intuitive performance is the frequency of large-scale fog and haze,and air quality problems has become one of the hot issues of common concern to the public.As an important component in the atmospheric environment structure,the aerosol impact on climate change and environmental effects,and the aerosol pollution is an important part of air pollution.AOD?Aerosol Optical Depth?,a parameter to describe the weakening of aerosol for radiative transfer,is a dimensionless quantity to describe the atmospheric turbidity,but also a key parameter to evaluate the degree of air pollution and study the environmental effects and climatic effect of effects.Get accurate aerosol optical thickness values,not only to better understand the energy balance in earth-atmosphere system,but also play an important role in the prevention and control of air pollution.With the current worsening of air quality,the studies for obtain related parameters and characteristics analysis of aerosol has become one of the hot spots in atmospheric field.AOD acquisition methods include satellite remote sensing and ground-based remote sensing,by means of ground-based remote sensing aerosol optical thickness with the advantages of high precision,high temporal resolution.But the point data cannot analyzing the characteristic of the change in wide range of scales.Satellite remote sensing to make up for the lack of ground-based remote sensing,can achieve real-time monitoring on a large area.Satellite received electromagnetic radiation from the contribution of surface and atmospheric,so remote sensing image contains atmospheric radiation path of the radiation information and surface information.Using solar radiation normalized the relations of the radiation value,path radiation and surface radiation to the relations of the apparent reflectivity *,surface reflectivity and path radiation equivalent reflectivity 0.0 is related to AOD,atmospheric transmittance T and hemispherical reflectance S.So,obtain AOD from 0 based on apparent reflectivity involved two key issues: removal the contribution value of surface reflection noise and aerosol mode.Taking Jiangsu province as the study area,firstly using Dark Dense Vegetation removal the contribution value of surface reflection noise,then taking 6S radiative transfer model consider the relation of AOD with 0?S?T,and obtain AOD through lookup table.Based on the above theory,the papers take MODIS L1 B image data as experimental data,inversed distribution of AOD in Jiangsu Province from October 2014 to May 2015,and analyzed the inversion results,the main research results of this paper are as follows:?1?Inversed distribution of AOD in Jiangsu Province from October 2014 to May 2015 the value of inversion results between 0-1.95,take the CE-318 AOD data as the actual value,and contrastive Analysis with inversion results,evaluating the accuracy of inversion.A total of 20 sets of comparative data,the absolute error and relative error was 0.1 and 19.58% respectively,the correlation coefficient was 0.731,at confidence level of 0.01 is significant correlation,confirmed the inversion results is good.?2?Based on the inversion results,analysis the spatial and temporal distribution of AOD in Jiangsu Province,analysis AOD distribution differences of the winter and spring time.The average of AOD was 0.68 in winter and AOD distribution histogram concentrated in 04-0.6;the average of AOD was 0.71 in winter and AOD distribution histogram concentrated in 04-0.9.In space,the AOD has a higher distribution in the south than the north.It mainly related with pad surface vegetation,the level of urbanization and population density.This paper mainly analyzed the relationship between aerosol optical thickness and surface vegetation index,the results showed a negative correlation between the two.?3?Analyzed relationship between PM_2.5 mass concentration and AOD,do correlation analysis for PM_2.5 data of automatic air quality monitoring sites and the average value of retrieval result in the range of 5×5 km center around the site by SPSS.The results of correlation Pearson correlation coefficient was 0.578,significantly correlated at 0.01 level of confidence,confirming the feasibility of using satellite remote sensing retrieval of AOD on the ground PM_2.5 mass concentration monitoring.?4?In determining the aerosol optical thickness and PM_2.5 mass concentration was significantly correlated,build AOD-PM_2.5 regression model.10 sites data selected as validation data,the remaining data as the experimental group,building regression models,the model of winter and spring was: y = 74.487 x + 16.181,spring: y = 68.2x+ 20.520,respectively,x is aerosol optical thickness,y is PM_2.5 mass concentrations.Take the validation data into regression model,derived PM_2.5 mass concentrations estimates,and compare with measured values to verify the applicability of the model.