考虑AOD差异的高分一号卫星宽视场相机大气校正

Atmospheric Correction of GF-1 Satellite WFV Camera Considering AOD Difference

针对当前对高分卫星宽视场相机大气校正不够准确的问题,提出了一种考虑气溶胶时空变化差异的大气校正方法。对比了6S和6SV对气溶胶变化反应的敏感性,发现6SV对WFV相机模拟效果更好。此外,利用6SV辐射传输模型采用气溶胶均值和逐像元2种方式对GF-1卫星WFV相机进行了大气校正实验,并模拟计算了气溶胶误差对WFV相机不同波段大气校正的影响。定量分析与实验结果表明:结合MOD04产品和6SV可以实现对GF-1卫星WFV相机影像进行准确地逐像元大气校正,相比较传统普遍采用的均值气溶胶大气校正方法,逐像元大气校正方法能更好地还原不同地物的光谱反射曲线;通过模拟计算实验发现,15%的气溶胶平均误差带来的WFV相机蓝、绿、红和近红外4个波段大气校正误差分别为-0.0280、-0.0160、-0.0077和0.0095。

In order to solve the problem that the atmospheric correction of GF satellite WFV camera is not accurate enough,an atmospheric correction method considering the difference of aerosol optical depth(AOD)spatiotemporal variation is proposed.The sensitivity of 6S and 6SV to AOD changes is compared,and it is found that 6SV is better for WFV camera simulation.Using 6SV radiation transfer model,the atmospheric correction experiments of GF-1 satellite WFV camera are carried out by means of AOD mean and pixel by pixel,and the influence of AOD error on atmospheric correction of different wave bands of WFV camera is simulated and calculated.Quantitative analysis and experimental results show that,combining the MOD04 product and 6SV,the GF-1 satellite WFV camera image can be accurately atmosphere corrected pixel by pixel.Compared with the traditional atmospheric correction method,the pixel by pixel atmospheric correction method can better restore the spectral reflection curves of different objects.Through the simulation calculation experiment,it is found that the atmospheric correction errors of the four bands of WFV camera blue,green,red and near infrared caused by 15%AOD average errors are-0.0280,-0.0160,-0.0077 and 0.0095,respectively.