Absolute atmospheric correction (AC) methods require a description of the components in the atmospheric profile. The output of these methods is an image that matches the reflectance of the ground pixels with a maximum estimated error of 10%, provided that atmospheric profiling is adequate enough. This image can be used for flux quantifications, parameter evolution assessments, etc., as mentioned above.
The advantage of these methods is that ground reflectance can be evaluated for any atmospheric condition, altitude and relative geometry between the Sun and satellite. The disadvantage is that the atmospheric profiling required for these methods is rarely available. To address this inconvenience, various absolute AC methods have been developed that have different requirements in relation to the atmospheric profiling data—and differences in the accuracy of the results.