近红外通道辐射测量误差对水体大气校正的影响  

Influence of Measurement Errors of Radiation in NIR Bands on Water Atmospheric Correction

作　　者：许华[1,2] 李正强[1,2] 尹球[3] 顾行发[1,2] 

机构地区：[1]国家环境保护卫星遥感重点实验室,北京100101 [2]中国科学院遥感应用研究所,北京100101 [3]上海市卫星遥感与测量应用中心,上海200083

出　　处：《光谱学与光谱分析》2013年第7期1781-1785,共5页Spectroscopy and Spectral Analysis

基　　金：国家(973)项目(2010CB950801);国家科技重大专项"高分专项"(E0104/1112/XX-004);国家科技重大专项"水专项"(2009ZX07527-006)资助;国家自然科学基金项目(41222007)

摘　　要：一类水体的标准大气校正算法利用两个近红外通道(748和869nm)的辐射比值选择气溶胶模型,然后外推估算各波长的气溶胶贡献,实现离水反射率的反演。两个近红外通道的辐射探测值的不确定性会直接影响反演精度。从数学形式上研究近红外通道测量误差在大气校正中的传递机制,通过敏感性试验分析不同光学厚度和气溶胶模型条件下离水反射率的反演误差分布。结果表明,两个近红外通道的测量误差组合情况对反演结果精度影响程度不同,同号时误差较小,异号时误差较大;气溶胶模型中的细粒子组分越多,反演的误差越大;光学厚度越大,反演误差也越大。For standard algorithm of atmospheric correction of water, the ratio of two near-infrared （NIR） channels is selected to determine an aerosol model, and then aerosol radiation at every wavelength is accordingly estimated by extrapolation. The uncer- tainty of radiation measurement in NIR bands will play important part in the accuracy of water-leaving reflectance. In the present research, erroneous expressions were derived mathematically in order to see the error propagation from NIR bands. The errors distribution of water-leaving reflectance was thoroughly studied. The results show that the bigger the errors of measurement are made, the bigger the errors of water-leaving reflectance are retrieved, with sometimes the NIR band errors canceling out. More- over, the higher the values of aerosol optical depth or the more the component of small particles in aerosol, the bigger the errors that appear during retrieval

关 键 词：近红外 水体大气校正 离水反射率 误差传递 

分 类 号：TP79[自动化与计算机技术—检测技术与自动化装置]