一种不同植被覆盖条件下的气溶胶光学厚度反演方法

An Inversion Algorithm for Aerosol Optical Depth Based on Different Vegetation Covers

提出一种在不同植被覆盖条件下的气溶胶光学厚度反演算法。这种算法基于影像自身的波段间信息和关系,通过选取影像中植被混合比差距较大的像元,使用可见光到近红外波段(400～900 nm)的光谱信息,反演得到气溶胶光学厚度。详细介绍了这种反演方法原理和操作流程,并分别使用模拟数据和真实遥感影像的反演对本方法进行验证。通过模拟数据的反演,这种方法反演结果与真实值的拟合系数(R2)达到0.981 8,均方根误差(RMSE)达到0.055;同时使用该算法反演和校正中巴资源卫星(CBERS)CCD影像。分析校正前后的影像,校正结果明显增强了影像对比度,同时还反映出影像能见度的情况分布,经过大气校正后,可以使得地物更加接近真实地表反射率,有利于影像的定量化应用。

An inversion algorithm for aerosol optical depth based on different vegetation covers is introduced.This algorithm is designed to estimate the precise Aerosol Optical Depth（AOD） by using the visible to near-infrared spectral bands（400-900nm） information.We describe the principle of this method and outline the main steps in this correction process.Simulated data and remotely sensed images are used to validate this algorithm.The fitted coefficient R2equals to 0.981 8 and the error of root-mean-square（RMS） equals to 0.055,which shows that the method has a good performance.Moreover,a CBERS（China-Brazil Earth Resource Satellite） CCD image is selected to validate this method.The surface reflectance after atmospheric correction is much closer to the real spectrum.The method is conducive to the quantitative application of CCD images.