Simulation of In Situ Visible Radiometric Measurements

Abstract The collection of high-quality in situ measurements is a key component for the calibration and validation of space-borne radiometric data and the development of inversion schemes for retrieving higher level product maps underpinning climate-change studies. In situ radiometric measurements to compute quantities such as the remote sensing reflectance are, however, subject to different perturbing factors. Scope of this chapter is to discuss perturbations due to large deployment structures, such as ships and oceanographic towers, as well as instrument self-shading and sea-surface light focusing. The radiance distribution induced by these perturbing elements cannot be evaluated analytically by directly solving the radiative transfer equation. Among numerical simulations, the use of deterministic approaches is partially limited by the absence of translational invariance in the perturbed light field. On the other hand, results show that Monte Carlo simulations of radiometric perturbations represent an effective mean for enhancing the quality of field measurements by offering the possibility to define correction schemes and refine measurement protocols.