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Updated: Jun 10, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Summary
Tropical subvisual cirrus clouds exhibit a maximum infrared polarization signature of 1%. This signature arises from randomly oriented ice crystals, as determined by radiative transfer calculations.
Area of Science:
- Atmospheric science
- Cloud physics
- Radiative transfer
Background:
- Cirrus clouds play a significant role in Earth's radiative balance.
- Understanding the microphysical properties of cirrus clouds is crucial for climate modeling.
- Infrared polarization can provide insights into cloud particle orientation and composition.
Purpose of the Study:
- To investigate the potential infrared polarization signature of tropical subvisual cirrus clouds.
- To determine the influence of randomly oriented ice crystals on polarization signals.
- To utilize radiative transfer calculations for predicting polarization characteristics.
Main Methods:
- Radiative transfer calculations were performed to simulate infrared radiation interaction with cirrus clouds.
- The study focused on subvisual cirrus cloud conditions typical of tropical regions.
- The model incorporated randomly oriented ice crystals as the primary scattering medium.
Main Results:
- A maximum infrared polarization signature of up to 1% was predicted for tropical subvisual cirrus.
- The presence and orientation of ice crystals were identified as key factors influencing the polarization signature.
- The findings highlight the sensitivity of infrared polarization to microphysical properties.
Conclusions:
- Tropical subvisual cirrus clouds can produce a detectable infrared polarization signature.
- This signature is primarily influenced by randomly oriented ice crystals.
- Infrared polarimetry shows promise as a tool for remote sensing of cirrus cloud properties.
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