基于时间序列技术的NOAA/AVHRR陆地气溶胶遥感反演研究

大气气溶胶是地气辐射平衡的重要影响因子。利用卫星观测资料能够反演气溶胶的时空分布，进而为研究气候变化提供支持。AVHRR是唯一能够提供30年对地观测资料的卫星传感器。由于AVHRR传感器通道有限，其在陆地气溶胶反演方面进展缓慢，难以提供全球产品。本研究将针对AVHRR传感器特点，建立地气耦合的气溶胶光学厚度遥感反演模型，利用时间序列技术实现地气分离，同时获得陆地气溶胶光学厚度和地表二向性反射参数。为解决气溶胶遥感反演中类型参数确定的难题，本研究将基于地面长年观测资料和其他辅助数据，建立AVHRR陆地气溶胶反演先验知识库。通过选取不同实验区进行反演测试，评价反演算法的适用性和反演精度，之后应用于中国地区大尺度气溶胶光学厚度产品样例生产。通过本项研究建立的基于时间序列技术的AVHRR陆地气溶胶遥感反演算法，有望实现30年中国地区的气溶胶产品生产，进而为全球气候变化研究提供必要的数据支撑。

Atmospheric aerosols play an important role in the radiation balance and global climate changing. Satellite remote sensing is an effective method to obtain aerosol's spatial and temporal distribution. Advanced Very High Resolution Radiometer (AVHRR) is the only sensor which can provide the Earth observation datasets as long as 30 years. However, it is difficult to retrieve aerosol over land and provide the global products because of the band limitation of AVHRR sensor. In our study, we will focus on modeling and inversion from AVHRR data. Aerosol optical depth and bidirectional reflectance distribution function (BRDF) parameters will be retrieved by a new time series technique. To determined aerosol's type, prior knowledge is needed. We will test our algorithm over many different sites. After evaluating the accuracy and feasibility of our algorithm, we will apply it to AVHRR data for the generatation of aerosol product over China. From our study, it is possible to get aerosol datasets over 30 years and support the climate changing study.