Light scattered by the surface–atmosphere system is partially polarized and provides useful information about aerosols and the underlying surface as polarized signals are sensitive to angular information about aerosols. To fully utilize this information, separating polarization signals of the atmosphere and surface by using the bidirectional polarized distribution function (BPDF) is necessary. However, although several BPDF models have been developed, the effects of the uncertainties of these models on the top-of-the-atmosphere (TOA) have not been fully investigated. In this study, we utilize the newly released POLarization and Directionality of the Earth's Reflectances (POLDER) dataset as a measured surface polarized reflectance dataset to parameterize the six currently used BPDF models. The measured and modeled surface polarized reflectances are used as inputs to vector radiative transfer models by statistical aggregating schemes considering all possible POLDER geometries. The root mean square errors between the measured and modeled polarized reflectances at the TOA decreased to 60–75% of the root mean square errors between the measured and modeled polarized reflectances at the surface and further decreased to a relatively low level (20%–30%) when the aerosol optical depth (AOD) increased. The BPDF uncertainty mainly affects the aerosol property retrievals mainly at low aerosol loadings. However, the accuracy of the surface BPDF required to obtain a sufficiently accurate retrieval at small AODs is still unknown. This study provides further insights that are valuable for understanding the coupling effect of the surface and atmosphere and important methods and information for retrieval of aerosol properties.

由表面-大气系统散射的光被部分偏振，并提供有关气溶胶和下层表面的有用信息，因为偏振信号对有关气溶胶的角度信息敏感。为了充分利用此信息，必须使用双向极化分布函数（BPDF）分离大气和地面的极化信号。但是，尽管已经开发了几种BPDF模型，但是尚未完全研究这些模型的不确定性对大气层顶部（TOA）的影响。在这项研究中，我们利用新发布的地球反射率的极化和方向性（POLDER）数据集作为测量的表面偏振反射率数据集来参数化当前使用的六个BPDF模型。通过考虑所有可能的POLDER几何形状的统计汇总方案，将测量和建模的表面偏振反射率用作矢量辐射传输模型的输入。在TOA处测量和建模的偏振反射率之间的均方根误差降低到表面处测量和建模的偏振反射率之间的均方根误差的60–75％，并进一步降低到相对较低的水平（20％–30 ％）当气溶胶光学深度（AOD）增加时。BPDF的不确定性主要影响气溶胶特性的恢复，主要是在低气溶胶负荷下。但是，在小AOD处获得足够准确的检索所需的表面BPDF的精度仍然未知。