Deciduous Forest Radiation Regimes: Effects of Forest Structure, Phenology and Earth-Sun Geometry Upon Their Spatial, Temporal and Spectral Variability.

This report summarizes a research effort to quantify the spatial and temporal variations of solar radiation within a deciduous forest canopy and to test whether canopy radiation transfer models, based on the assumption of spatial homogeneity, are applicable in a deciduous forest stand. The specific objectives of this effort were to: (1) Quantify the incoming and outgoing fluxes of solar and terrestrial radiation and evaluate their spatial and temporal variations; (2) Relate these flux measurements and their variabilities to phenological changes in forest structure and to seasonal changes to earth-sun geometry; and (3) Test selected canopy radiation transfer or phytoactinometric models against data observed in and above a deciduous forest.