The effect of aerosol light-extinction coefficient correction on urban aerosol scale height

• Main Authors: Rui-ren Cheng, 鄭瑞仁
• Other Authors: Chung-te Lee
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/97765395152941530495

碩士 === 國立中央大學 === 環境工程研究所 === 99 === It''s important pollutants that affect the global environmental changes caused by atmospheric aerosol extinction of solar radiation can cooling and warming the atmospheric. The light extinction coefficient is the sum of the light scattering and light absorption coefficients, therefore, it''s the correct atmospheric light extinction coefficient is needed for evaluation of aerosol effects on solar radiation. To assess the aerosol optical properties in Taipei metropolitan area, the aerosol extinction coefficient have been observed at Hsin-Chuang supersite station in Taipei, cause of the observed data didn''t corrected for the truncation error and for the non-idealities in angular intensity distribution of the light and didn''t took explicitly into account the fact that the filter-loading correction, the multiple scattering correction and the scattering correction. Therefore, the corrected methods are according to Anderson and Ogren (1998) and Colluad Coen et al. (2010). The study investigates the real aerosol scattering coefficient is higher than original value 15%, the real absorption coefficient is lower than original values 8% and the real extinction coefficient is higher than original value 13%, it directly affected is increase of single scattering albedo,(SSA), the real SSA is higher than original value 3%,meanwhile,the scale height is determined by aerosol extinction coefficient and aerosol optical depth, the real height is lower than 13%it represents the aerosol distribution height in vertical is lower than original height. This paper use LIDAR to measured the vertically resolved of extinction is co-owned by the Research Center for Environmental Change, Academia Sinica and the Department of Atmospheric Science, National Taiwan University in 2008~2009.The result found scale height have strong seasonal cycle and daily cycle, it''s higher in spring, shows there are often Asian dust storms events during spring. This paper, now, investigate the change of aerosol extinction coefficient and scale height in dust storms events, festivals, PM2.5 high concentration events and normal days, respectively.