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Updated: Jul 12, 2026
09:34
Extraction and Characterization of Surfactants from Atmospheric Aerosols
Published on: April 21, 2017
Evidence for liquid-phase cirrus cloud formation from volcanic aerosols: climatic implications
Science (New York, N.Y.)
|July 24, 1992
Summary
Volcanic aerosols enable supercooled water droplets in cirrus clouds, crucial for cirrus formation. This suggests a previously unknown volcano-cirrus cloud climate feedback loop.
Area of Science:
- Atmospheric Science
- Cloud Physics
- Climate Science
Background:
- Cirrus clouds are primarily composed of ice crystals.
- Supercooled liquid water (SLW) in cirrus clouds at very cold temperatures is rare.
- The formation mechanisms of SLW in cirrus clouds remain an active area of research.
Purpose of the Study:
- To identify and characterize supercooled liquid droplets in cirrus uncinus cloud heads.
- To investigate the role of these droplets in cirrus cloud formation.
- To explain the phenomenon of supercooled droplets at temperatures below -40°C.
Main Methods:
- Utilizing polarization lidar measurements from Project FIRE (First ISCCP Regional Experiment).
- Analyzing data for the presence of supercooled droplets in specific cloud formations.
- Investigating the properties of cloud condensation nuclei associated with these droplets.
Main Results:
- Supercooled droplets were identified in cirrus uncinus cell heads between -40°C and -50°C.
- These short-lived liquid droplets appear to significantly contribute to cirrus cloud formation.
- Freezing-point depression, linked to large volcanic cloud condensation nuclei, explains this rare observation.
Conclusions:
- Volcanic aerosols can facilitate the existence of supercooled water in cirrus clouds.
- This finding implies an unrecognized volcano-cirrus cloud climate feedback mechanism.
- Further research is needed to understand the implications of this feedback on climate.
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