Analytical model for radiative transfer including the effects of a rough material interface

Area of Science:

• Optics
• Fluid Dynamics
• Atmospheric Science

Background:

• Accurate modeling of light interaction with natural water bodies is crucial for remote sensing and optical oceanography.
• Previous models often simplify the complex air-water interface, neglecting the impact of random surface roughness on radiative transfer.

Purpose of the Study:

• To develop and validate analytical models for computing reflected and transmitted radiance from a source above a water surface.
• To incorporate the effects of random surface roughness at the air-water interface into radiative transfer calculations.

Main Methods:

• Utilized radiative transfer theory in continuous optical media separated by a discontinuous, randomly rough air-water interface.
• Applied geometric optics and regular perturbation methods to Snell's law to approximate bidirectional reflection and transmission functions.
• Employed small-angle scattering approximation for analytical solutions, accounting for scattering, absorption, and diffusive effects.

Main Results:

• Developed analytical models that capture scattering, absorption, and diffusive effects of light interacting with a rough air-water interface.
• Validated the analytical model results against established Monte Carlo simulations.
• Compared the approximated bidirectional reflection function with another established analytical model.

Conclusions:

• The developed analytical models provide a robust framework for understanding light propagation through the atmosphere and water, considering complex air-water interface dynamics.
• The inclusion of random surface roughness significantly improves the accuracy of radiative transfer predictions in aquatic environments.
• The validated models offer a valuable tool for applications requiring precise optical modeling of air-water systems.