中文摘要：

利用TERRA和AQUA共同反演气溶胶光学厚度和地表反射率特征，对其原理及方法进行了详细的讨论。通过Terra和Aqua两颗卫星对同一地点的不同角度的观测，结合多个光学通道的信息，反演了北京地区光学厚度及地表反射率信息。反演的气溶胶光学厚度同地面观测的结果相比具有很好的一致性。同时，对地表反射率及气溶胶波长指数等也进行了讨论和对比，结果显示，对北京地区，MODIS1通道地表反射率和7通道地表反射率的比在0．66左右，3通道和7通道的比在0．28左右。相比于NASA暗背景全球反演算法中1、3通道和7通道的比为0．50和0．25的处理方法，反演得到的气溶胶光学厚度结果也较好。

英文摘要：

MODIS instruments aboard on Terra and Aqua are used to synchronously retrieve aerosol optical depth （AOD） and surface reflectance properties, and the main principles and methods to derive aerosol products from satellites are discussed in detail. The aerosol optical depth and surface reflectance over Beijing are obtained by applying the multi-channel measurements from Terra and Aqua in their different observing angles to the same surface site. The satellite retrieval results are well consistent with surface sun-photometer observations. The retrieved results of surface reflectance and aerosol Angstroem exponent are discussed by comparing them with surface measurements and literature results. Our results show that in Beijing region the reflectance radio is about 0.66 of MODIS channel 1 over channel 7 and about 0.28 of MODIS channel 3 to channel 1. Compared with the data used by dark dense vegetation background algorithm proposed by NASA for global retrieval, i.e. 0.50 and 0.25 on the two channels, the final AOD results from our method are more consistent with the surface sun-photometer observations.