中国海域MODIS气溶胶光学厚度检验分析

摘要

利用MODIS的Collection 005版本(MODIS-C005)数据的气溶胶光学厚度(AOT)产品,与我国海域多个AERONET观测站点太阳光度计测量得到的AOT结果进行了对比分析,对MODIS-C005数据的气溶胶产品在我国海域进行了验证,并对验证方法进行了探讨.结果表明,MODIS-C005的AOT在我国海域与AERONET站陆基观测到的AOT具有非常好的一致性,相关系数达到0.9以上.通过尝试不同的验证方法,发现验证数据的空间采样窗口大小的选择对于验证效果具有较大的影响,在中国海域可以使用30 km×30 km的空间采样窗口.通过MODIS-C005的AOT与AERONET站观测值在中国各个海区的比较,证明MODIS_C005的AOT在550 nm满足美国NASA的设计要求,误差控制在±0.05±0.05 τ,适用于我国海域,可以用于中国海域的气象和海洋等科学研究.%The Aerosol Robotic NETwork(AERONET) provides the necessary ground-based observa-tion to validate and assess the applicability of the latest version MODIS Collection 005 aerosol optical thickness(AOT) products over the China sea for the fist time. Based on the two kinds of data,the methods of validation over the China Sea are discussed. The validation results show that the MODIS Collection 005 AOT has a good relationship with the AERONET AOT, and their correlation coefficient is greater than 0. 9 over the China sea. By testing different validation methods, we find that the window size of MODIS data can influence the validation result,and the 30 km ×30 km window size is the best over the China sea. Finally, the comparison of MODIS-and AERONET-derived AOT respectively overdifferent regions of the China Sea suggests that the MODIS Collection 005 AOT at 550 nm correspondwith the error standard of NASA and most of its error can be controlled under±0. 05±0. 05τ-over the China Sea, so MODIS Collection 005 AOT is creditable over the China Sea for science research.