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Updated: Jun 17, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Summary
A simplified physical model explains cirrus cloud radiance. Thermal emission is key, significantly exceeding scattered light and closely matching observed cloud radiance characteristics.
Area of Science:
- Atmospheric Physics
- Cloud Radiance Modeling
Background:
- Cirrus clouds significantly influence Earth's radiation budget.
- Accurate modeling of cirrus cloud radiance is crucial for climate studies.
Purpose of the Study:
- To develop a simplified physical model for cirrus cloud radiance.
- To explain measured cirrus cloud radiance characteristics.
Main Methods:
- Derived a simplified physical model for cirrus cloud radiance (8-13 micrometers).
- Separately analyzed thermal emission and scattering of Earth's irradiance.
- Computed scattering diagrams for ice spheres using diffraction theory and specular reflection.
Main Results:
- Thermal emission was found to significantly exceed scattered radiance across all zenith angles.
- Computed radiance values closely matched measured cloud radiance data.
Conclusions:
- The simplified physical model effectively explains observed cirrus cloud radiance.
- Thermal emission is the dominant component of cirrus cloud radiance at these wavelengths.
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