According to this analysis, these theoretical models have different applicability for different ranges. For a more detailed study of the applicability of these models, 19 sets of optical properties were selected, which all have the same () but different . For equal to 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and respectively, we can obtain the reduced albedos ranging from 0.5 to 0.99. By comparing the derivation error, the best model to derive and at different ranges of using the six theoretical models is summarized in Table 1. First, this means that the best forward model of is used to derive and simultaneously and then the derivation result of is used to be the best result of ; secondly, the best forward model of is used to derive and simultaneously, and then the derivation result of is used to be the best result of .