Simplified expressions for radiation scattering in canopies with ellipsoidal leaf angle distributions

The ability to simulate the surface energy balance and microclimate within a plant canopy is contingent upon accurate simulation of radiation exchange within the canopy. Accurate radiation simulations require some assumption of leaf angle distribution to compute transmissivity, reflection and scattering of radiation. The ellipsoidal leaf angle density function can very closely approximate real plant canopies but requires complex integrations for different combinations of leaf area index, incident radiation angle, and density function. This paper presents close approximations (R2 > 0.99) to compute the transmissivity and scattering functions for elliptical leaf angle distributions that can be more easily implemented into simulation models.