Definitions

glob·al/glōbəl/ Adjective (adverb globally)
Spherical
of, relating to, or involving the entire world :
worldwide <a global system of communication>;
also : of or relating to a celestial body (planet).
ORIGIN French (1670 AD), globe + -al "worldwide, universal".

albedo/albeedo/ noun (pl. albedos)(chiefly Astronomy)
The proportion of the incident light that is reflected by a surface or ratio of light reflected from a surface.
ORIGIN Latin (1859 AD), L. albedo, lit. "whiteness" from albus "white".

fAPAR/
fraction of Absorbed Photosynthetically Active Radiation (fAPAR) is the fraction of the incoming radiation in the 400-700 nm band absorbed by the leaves, which can be used for photosynthesis. Definitions differ according to illumination conditions and leaf state.

LAI/
Leaf Area Index (LAI) is defined as the one-sided green leaf area per unit ground surface area (with extensions for needle-leaf trees). It is a unitless quantity (m2m-2). Depending on the retrieval method, its exact definition varies. BHR-TIP retrieves effective LAI, consistent with existing implementations in large-scale climate and Earth system models, and is related to "true" LAI through a canopy-dependent structure factor.

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