Normalized Differential Vegetation Index (NDVI), usually calculated by surface reflectance at red and near-infrared bands (NDVI_Surf), which is an essential index in remote sensing. NDVI_Surf is generally used to discriminate different surface cover types and adopted in many surface models as a vital adjustable parameter to estimate the surface reflectance in remote sensing aerosol retrieval. However, NDVI_Surf is challenging to obtained directly and usually calculated by the red and near-infrared reflectance at the top of atmosphere (NDVI_TOA). NDVI_TOA is very susceptible to the atmosphere with different angles. If NDVI_Surf is replaced by the NDVI_TOA, it will cause an error of surface reflectance estimation and then make the wrong aerosol retrieval. In this study, Second Simulation of a Satellite Signal in the Solar Spectrum, Vector version (6SV) radiative transfer code was used to analyze the effects of NDVI_TOA on a surface Bidirectional Polarization Distribution Function (BPDF) model under different atmosphere and multi-angles conditions. The results display that the NDVI_TOA decreases with the rise of AOD. Within scattering angle (SA) of 60° to 115°, the influences of NDVI_TOA on BPDF are great and increases with the AOD reduces. Within the SA between 115° to 180°, the effects of NDVI_TOA on BPDF are small and remain unchanged with the AOD decreases. The simulation and analysis results have a great significance for polarized aerosol retrieval.

Date Published: 18 December 2019
PDF: 7 pages
Proc. SPIE 11338, AOPC 2019: Optical Sensing and Imaging Technology, 1133834 (18 December 2019); doi: 10.1117/12.2547899

Published in SPIE Proceedings Vol. 11338:
AOPC 2019: Optical Sensing and Imaging Technology
John E. Greivenkamp; Jun Tanida; Yadong Jiang; HaiMei Gong; Jin Lu; Dong Liu, Editor(s)