The fine-mode aerosol absorption optical depth（AAOD）retrieved from the Aerosol Robotic Network（AERONET）has been used in previous studies to calculate the radiative forcing of black carbon（BC）aerosol,assuming tha...The fine-mode aerosol absorption optical depth（AAOD）retrieved from the Aerosol Robotic Network（AERONET）has been used in previous studies to calculate the radiative forcing of black carbon（BC）aerosol,assuming that the absorption by fine-mode aerosols（diameter ≤ 1 μm）is primarily from BC while the absorption by larger particles（diameter 1 μm）is principally from dust.In the present study,the Community Earth System Model was used to simulate and quantify the contribution of fine-mode dust to fine-mode AAOD in eastern China（29–41°N,104–122°E）—an area where concentrations of BC are high.The simulated fine-mode dust concentrations were constrained by observations from nine sites belonging to the Chinese Meteorological Administration Atmosphere Watch Network.Averaged over eastern China,the simulated annual mean fine-mode dust AAOD was 3.6 × 10-3,with the maximum AAOD in spring and the minimum value in winter.The contribution of fine-mode dust to the total fine-mode AAOD（sum of fine-mode dust,BC,and organic carbon）in winter,spring,summer,and autumn was 3.4%,25.2%,12.5%,and 14.9%,respectively,with an annual mean value of 15.1%.The results indicate the importance of removing fine dust AAOD when the AERONET fine-mode AAOD is used for calculating the radiative forcing of BC in eastern China.展开更多
基金supported by the National Basic Research Program of China(973 Program,[grant number 2014CB441202])the Strategic Priority Research Program of the Chinese Academy of Sciences[grant number XDA05100503]
文摘The fine-mode aerosol absorption optical depth（AAOD）retrieved from the Aerosol Robotic Network（AERONET）has been used in previous studies to calculate the radiative forcing of black carbon（BC）aerosol,assuming that the absorption by fine-mode aerosols（diameter ≤ 1 μm）is primarily from BC while the absorption by larger particles（diameter 1 μm）is principally from dust.In the present study,the Community Earth System Model was used to simulate and quantify the contribution of fine-mode dust to fine-mode AAOD in eastern China（29–41°N,104–122°E）—an area where concentrations of BC are high.The simulated fine-mode dust concentrations were constrained by observations from nine sites belonging to the Chinese Meteorological Administration Atmosphere Watch Network.Averaged over eastern China,the simulated annual mean fine-mode dust AAOD was 3.6 × 10-3,with the maximum AAOD in spring and the minimum value in winter.The contribution of fine-mode dust to the total fine-mode AAOD（sum of fine-mode dust,BC,and organic carbon）in winter,spring,summer,and autumn was 3.4%,25.2%,12.5%,and 14.9%,respectively,with an annual mean value of 15.1%.The results indicate the importance of removing fine dust AAOD when the AERONET fine-mode AAOD is used for calculating the radiative forcing of BC in eastern China.
