Angular and polarization response of vegetation, bare soil and water from ADEOS POLDER data over India

Abstract

In this letter, the angular variations of total and polarized reflectances of vegetation, bare soil and water with respect to different Sun-target-view angles, obtained from ADEOS (Advanced Earth Observation Satellite) POLDER (Polarisation and Directionality of Earth Reflectances) measurements acquired over the Indian sub-continent during 7 November 1996, are analysed at three wavelengths, namely, 443, 670 and 865 nm. The POLDER measured reflectances are approximately corrected for molecular and aerosol effects due to path radiance assuming a single layer, horizontally homogeneous atmosphere. The variation of total and polarized reflectances of three targets as a function of view zenith and relative azimuth angles are presented. The corrected target polarized reflectances show a monotonic decrease with relative azimuth and view zenith angles. A semi-empirical model was fitted to the corrected total reflectances for the three targets at three wavelengths. Statistical analysis of regression coefficients show that the coefficient corresponding to normalized reflectance, k0, is physically significant.