Application Of Aerosol Optical Properties Dervied From Satellite Remote Sensing To The Atmospheric Pollution Monitoring

With the rapid development of the national economy, atmospheric pollution has become an important part of environmental protection. Directly and indirectly, aerosols affect the climate, since they scatter and absorb radiation and also alter the cloud microphysical properties. And the aerosol optical properties are closely related to the environmental pollution. Traditional in-situ stations for atmospheric pollution monitoring are very limited, while satellite remote sensing technologies show great advantages with large and continuous ground coverage. Aerosol optical properties derived from satellite remote sensing have great potential on the atmospheric pollution monitoring.Preliminary studies are carried out in this thesis, which concentrate on applications of aerosol optical properties derived from satellite remote sensing to the atmospheric pollution monitoring, both on land and over ocean respectively.On land, the Yushan campus of Ocean University of China, Shinan District of Qingdao is selected as the study area. The aerosol optical thickness (AOT) from MODIS level-2 product, AOT from in-situ skyradiometer measurements and corresponding air pollution index (API) data are collected for statistical regression analysis. Statistical models are given between AOTs and APIs for different seasons in the year, with correction of relative humidity effect on APIs. The possibility of atmospheric pollution monitoring using aerosol optical properties derived from satellite remote sensing is discussed.Over ocean, the East China Seas are selected as the study area. Based on MODIS level-1b product, a parameter called normalized difference aerosol index (NDAI) is proposed and calculated. NDAI is used together with OMI aerosol index (AI) to quantitative discriminate absorbing aerosols with non-absorbing aerosols. Match-up dataset between ship-borne skyradiometer observations with MODIS-derived AOTs is used for validation of the NDAI threshold. The detection of absorbing aerosols is also applicable for atmospheric pollution monitoring over the ocean.The preliminary conclusions are as follows:1. On land, generally there is low correlation between in-situ and MODIS-derived AOTs with APIs. After correction of relative humidity effect on APIs, the correlations are slightly improved for different seasons in the year. The correlation is usually higher in Spring and Autumn than in Summer and Winter. This may be caused by mis-interpretation of factors other than PM10 in API estimation.2. A quantitative method is proposed based on NDAI from MODIS for fast recognition of absorbing aerosols over the ocean, which overcomes the low-spatial-resolution disadvantage of AI from OMI. A NDAI threshold of 0.45 is proposed, with NDAI less than 0.45 for absorbing aerosols. This can be used for atmospheric pollution monitoring over the ocean. It is also useful for the improvement of the atmospheric correction algorithms for ocean color remote sensing.