A New Parameterization of Canopy Radiative Transfer for Land Surface Radiation Models  

作　　者：Feng ZHANG Yadong LEI Jia-Ren YAN Jian-Qi ZHAO Jiangnan LI Qiudan DAI 

机构地区：[1]Key Laboratory of Meteorological Disaster,Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster,Nanjing University of Information Science & Technology [2]State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,Chinese Academy of Sciences [3]Canadian Center for Climate Modeling and Analysis,University of Victoria

出　　处：《Advances in Atmospheric Sciences》2017年第5期613-622,共10页大气科学进展（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos.41305004,41675003 and 91537213);the PAPD (Priority Academic Program Development) of Jiangsu Higher Education Institutions

摘　　要：A new parameterization of canopy asymmetry factor on phase function,which is dependent on the leaf normal distribution and leaf reflection/transmission,is derived. This new parameterization is much more accurate than the existing scheme. In addition,the new solutions for both the diffuse and direct radiation can be obtained using the Eddington approximation. It is found that the direct radiation can be described as a function of the diffuse radiation. This new approach offers a substantial improvement in accuracy,as compared with the hemispheric constant method,for both isotropic and anisotropic cases. Given the analytical nature of the solution and its high accuracy,we recommend the new parameterization for application in land surface radiation modeling.A new parameterization of canopy asymmetry factor on phase function,which is dependent on the leaf normal distribution and leaf reflection/transmission,is derived. This new parameterization is much more accurate than the existing scheme. In addition,the new solutions for both the diffuse and direct radiation can be obtained using the Eddington approximation. It is found that the direct radiation can be described as a function of the diffuse radiation. This new approach offers a substantial improvement in accuracy,as compared with the hemispheric constant method,for both isotropic and anisotropic cases. Given the analytical nature of the solution and its high accuracy,we recommend the new parameterization for application in land surface radiation modeling.

关 键 词：radiative transfer CANOPY asymmetry factor Eddington approximation 

分 类 号：P422.1[天文地球—大气科学及气象学]