Calculating Recollision Probability Based on Airborne Lidar data for a Better Understanding of Canopy Radiation Regime

Photon recollision probability p serves as a critical bond between the spectral characteristics of the canopy at any wavelength and the reflectance, transmittance, or absorptance of the vegetation canopy. However, the estimation of p is predominantly accomplished through canopy structural parameters. In this work, we provide a method to estimate canopy p-value directly from Airborne Laser Scanning (ALS) data. The method was evaluated both in virtual experiments and field measurements. The virtual experiments employed the large-scale remote sensing data and image simulation model (LESS) to simulate virtual ALS scanning data based on three RAdiation transfer Model Intercomparison (RAMI) actual canopies. Our findings showed that p-values can be accurately estimated from ALS point clouds.