Primary Study On Retrieving AOD Above Land And Application Of Satellite Data To Monitoring Regional Atmospheric Pollution

Aerosol have a crucial role in local, regional and global air pollution problems. The high resolution of satellite data make the satellite be one important method to detect the whole earth, especially to explore the local and regional air pollution characteristic.One aim of this paper is to try to retrieve Aerosol Optical Depth (AOD) using an orientation method. It was premised that there was a month by month variation in the surface reflectance of one fixed ground point on the earth. And within one month the surface reflectance did not change with time. In one month, using satellite data and the routine meteorological observing data, the background figures of different hours of given month, like Beijing time 08: 00 of August, 09: 00 of September, and so on, could be founded, which was composed of the apparent reflectance under the cloudless and dry air condition. Because of the difference of the zenith and azimuth, the hour by hour background figures should be created. Thus some atmospheric parameters of the background figures were possible to been calculated when utilizing second simulation of satellite signal in the solar spectrum (6S) model. Applying these parameters to radiation transfer equation, the optical depth of atmosphere at any time was gained.When validating the above idea, four groups of optical depth at 550nm above Beijing meteorological station derived from GMS5 VISSR visible albedo data were calculated at Beijing time 08: 00, 11: 00, 14: 00, 17: 00 respectively. Comparing the values gained by retrieval method offered in this article and vertical attenuation data, a good coherence could been seen. After defining a test area i AOD values above dozens of meteorological stations within the area were retrieved. Then based on the station data, the grid data of the area were gained. The result shows the retrieved AOD could reveal the distribution of aerosol. Also the variety of the AOD distribution could be posted.In part two, within north China, years of the spatial and temporal evolutions of daily averaged pm10were analyzed, as while as the varieties of weather styles diagnosed, one fact was found that, controlled by certain synoptic systems, there always existed a territorial and synchronous air pollution, and some relatively fixed cities were always obviously influenced by the transmission and convergence belts produced by these systems. MODIS is one of the important EOS equipments. The visible and inferred data could help exports to retrieve AOD above land and monitor the serious pollution. Distribution of AOD at 550 ran retrieved from MODIS data can well approve the above fact.