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Updated: Jul 7, 2026
05:52
Observation and Analysis of Blinking Surface-enhanced Raman Scattering
Published on: January 11, 2018
Observation of Raman scattering by cloud droplets in the atmosphere
Applied Optics
|May 20, 1997
Summary
NASA
Area of Science:
- Atmospheric science
- Cloud physics
- Remote sensing
Background:
- Relative humidity in low-level clouds can exceed 100%.
- Spontaneous Raman scattering by liquid water in cloud droplets is a potential indicator of cloud liquid water content.
- Mie scattering analysis can differentiate cloud layers.
Purpose of the Study:
- To investigate the potential of spontaneous Raman scattering measurements for observing cloud liquid water.
- To analyze lidar data from low-level clouds during a field campaign.
Main Methods:
- Utilized NASA Goddard Space Flight Center's scanning Raman lidar.
- Measured Raman scattering in the water vapor channel.
- Analyzed data in conjunction with Mie scattering for cloud layer identification.
Main Results:
- Observed Raman scattering exceeding 100% relative humidity in low-level clouds.
- Interpreted excess scattering as spontaneous Raman scattering by liquid water.
- Identified two distinct cloud layers via Mie scattering, with significant Raman scattering only in the upper layer.
Conclusions:
- Spontaneous Raman scattering by liquid water in cloud droplets may offer a remote sensing method for observing cloud liquid water.
- The upper layer of the studied clouds showed significant liquid water Raman scattering.
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