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Estimation of Biophysical Variables from Satellite Observations

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Abstract

The supply of biophysical variables derived from satellite observations serves several applications related to agriculture, the environment, resource management and the climate. Moreover, these same variables may be acquired at a range of scales:. -at the very local level, the use of precision agriculture allows adapting cultural practices to the spatial variability of the plot;-across the landscape or territory, to manage the environment and natural resources;-at the continental or global scale for the study of climate, biogeochemical cycles and vegetation dynamics.

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... The retrieval includes the calculation of the Aerosol Optical Thickness at 550 nm (AOT), atmospheric water vapor column (WV), and in particular the Bottom-Of-Atmosphere (BOA) surface reflectance (ρ), used in further stages of Earth Observation research to derive other quantities, such as, for example, the fraction of absorbed photo-synthetically active radiation FAPAR [10]. Figure 1 presents a schematic sketch of the radiance calibration components, including the solar radiation reflected on the ground target pixel, the intrinsic atmospheric radiance and the surface-atmosphere interaction of the surroundings (adjacency effects). ...
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