DETERMINING SHORT-WAVE PLANETARY ALBEDO FROM THE SPECTRAL SIGNATURES OF LAND OCEAN FEATURES AND ALBEDO MAPPING USING NOAA AVHRR DATA

The spectral signature curves giving Lambertian reflection as a functi on of wavelength of various land-ocean features have been used to deri ve short-wave (0.3-2.5 mum) albedo from the narrow-band albedos in the spectral range similar to the visible and near-infrared channels of N OAA-11 AVHRR/2. The atmospheric albedos have been included for derivin g the Earth atmosphere albedo. Regression relationships between broad- band and the narrow-band albedos for the individual (scene dependent m odels) as well as composite features (scene independent model) have be en established. The latter model has been developed for use with coars e resolution remotely sensed data. Sensitivity analysis of models show s that the maximum uncertainty in albedo estimation is 14.62% due to t he measurement error of 1% in narrow-band albedos. The scene independe nt model has been applied to the NOAA-11 AVHRR/2 data covering the Ind ian subcontinent to estimate mean albedo and absorbed short-wave radia tion fluxes and compared with the published values derived from the NI MBUS-7 ERB data from 1979 to 1985. The results show that the albedo an d absorbed solar flux can be retrieved within the error of 6.25 and 2. 86%, respectively, using the scene independent model.