Study On Formative Mechanism And Remote Sensing Monitoring To Aerosol Pollution In Pearl River Delta

Aerosols play a crucial role in air pollution problems in Pearl River Delta region. This study focuses on the usability of MODIS LevelⅡAerosol Optical Depth(AOD) products (MOD04 and MYD04), genetic system of aerosols in the Pearl River Delta (PRD), the Image-Sounding-Observed data (ISO) pattern used in monitoring aerosols and its application in regional air pollution studies.A method based on MODIS1b data, which compare the linear relation of band1 with band7 and band3 with band7 in apparent reflectance respectively between the typical dark backgrounds with the typical background of PRD region, is used to validate the usability of dark background method in PRD region. The result indicates that there is good linear relation in apparent reflectance between band 1, 3 and band7 in PRD region. It shows that the dark background inversion method of MODIS AOD can be used in PRD region. The correlation between the time series of PM10, the hour mean value during TERRA satellite overpass Guangdong, and the time series of AOD in 4 environmental monitoring stations in Guangzhou among some days, which is unfit for atmospheric pollutants diffusion, from October to November, 2004, was analyzed. The study shows that the correlation is good and the MODIS LevelⅡAOD values from NASA can be used to monitoring the aerosols of the PRD region qualitatively or quasi-quantitatively.The aerosols property of PRD region was analyzed based on MODIS AOD product and statistic data. It shows that PRD region is one of high-aod-value centers in Guangdong Province. The aerosol sources of PRD region are from local emission and regional transportation. The aerosol pollution in PRD region occurs in all reasons, but mostly appears in the winter half. year. The properties above are determined by the genetic system of aerosols in the PRD region.Due to the dual nature of MODIS data and complexity of the genetic system of PRD region aerosols, it is a better way to utilize the image data, sounding data and observed data comprehensively. The ISO (Image-Sounding-Observed data) pattern, a multi-source data monitoring pattem, was used to analysis an aerosol polluted case during Oct.20 to 24, 2004.The study shows that ultra-fine particles formed by local automobile exhaust emission is the leading source of the aerosol pollutants. The high AOD pixels distributes along traffic lines。The pattern can be applied to monitoring, forewarning and controlling the aerosol pollution of PRD region effectively.