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Near infrared reflection spectra of artificial cumulus clouds
Applied Optics
|January 15, 2010
Summary
This study analyzes artificial cumulus cloud reflection spectra across various droplet sizes. Larger droplet sizes in clouds correlate with deeper reflectivity minima, matching natural cloud observations.
Area of Science:
- Atmospheric Science
- Cloud Physics
- Spectroscopy
Background:
- Understanding cloud radiative properties is crucial for climate modeling.
- Cumulus clouds significantly influence Earth's energy balance.
- Spectral analysis provides insights into cloud microphysical properties.
Purpose of the Study:
- To investigate the spectral reflectivity of artificial cumulus clouds.
- To determine the influence of droplet size on cloud reflectivity.
- To compare artificial cloud spectra with natural terrestrial cloud spectra.
Main Methods:
- Generating artificial cumulus cloud models with varying droplet sizes.
- Measuring reflection spectra from 1.0 to 2.4 micrometers.
- Applying corrections for gaseous absorption in spectral data.
Main Results:
- Identified distinct reflectivity minima at 1.16, 1.41, and 1.92 micrometers.
- Observed that reflectivity minima deepen progressively with increasing droplet size.
- Demonstrated strong agreement between artificial and natural terrestrial cloud reflection spectra.
Conclusions:
- Droplet size is a key factor determining the spectral reflectivity of cumulus clouds.
- Artificial cloud models can accurately replicate the spectral characteristics of natural clouds.
- The findings support the use of spectral reflectivity for remote sensing of cloud properties.
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