Aerosol Optical Thickness Retrieval Based On MODIS Data

With the rapid development of China’s economy, accelerate the process ofindustrialization and urbanization, environmental carrying increasing pressure in someareas, air pollution problems have become more serious. In most areas of ourcountry,aerosolhas become the primary pollutant of atmospheric aerosols affect theambient air quality. For the current realities of air pollution, the use of the spatialdistribution of air pollution monitoring and trend of satellite remote sensing hasimportant practical significance.AOD (Aerosol Optical Depth, AOD) is one of the important optical properties ofatmospheric aerosols to study aerosol content, the most commonly used indicator toassess the degree of air pollution, climate effects of aerosol research. Based on MODISL1B data, Dense Dark Vegetation method,6S model，Chongqing City as an example,the preparation of the corresponding inversion software, the aerosol optical thicknessChongqing city were inversion, its main contents and results are as follows:1, through the urban area of Chongqing, spring, summer, autumn and winter seasons ofmid-infrared surface reflectance analysis shows: no clouds in fine weather conditions,most of the urban area of Chongqing region surface reflectance infrared channel rates atthe Four Seasons0.15, in line with the use of dark pixel method conditions.2,6S model made by red, blue, mid-infrared channel sensitivity tests showed:continental aerosol model suitable for the urban area of Chongqing aerosol opticalthickness inversion, while the urban aerosol model is not applicable.3, remote sensing and ground observation data inversion results display: in spring andwinter the aerosol optical thicknessvalueof Chongqing are higher, at around1.0; insummer and autumn the aerosol optical thickness values are lower, below1.0.4,the aerosol optical thickness distribution of space: the main urban core city perennialhigh aerosol optical thickness, usually appear two aerosol optical thickness high valuearea (northern andcentral region), and sometimes there are three aerosol opticalthickness high value area (northern, central and southern region), aerosol opticalthickness of other areas are relatively lower. 5,the aerosol optical thicknessdistributionof time: the year aerosol optical thicknessof Jiangbei, Yubei, Yuzhong,Nanan, Jiulongpo, Shapingba central city were higherthan other aera;the aerosol optical thickness of the central city in Banan was higher thanother aera in some season; other areasalways lower.