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Updated: May 1, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
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Global atmospheric particle formation from CERN CLOUD measurements.
Eimear M Dunne1, Hamish Gordon2, Andreas Kürten3
1School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK.
Science (New York, N.Y.)
|November 3, 2016
Summary
Newly formed atmospheric aerosol particles are primarily created by sulfuric acid with ammonia or organic compounds. Ion influence is minor, suggesting cosmic rays have little impact on climate via particle nucleation.
Area of Science:
- Atmospheric Chemistry
- Aerosol Science
- Climate Science
Background:
- Global aerosol formation models are limited by insufficient laboratory data.
- Gas-phase chemistry models have long relied on laboratory kinetics measurements.
Purpose of the Study:
- To develop a global aerosol formation model using extensive laboratory data.
- To identify key components involved in atmospheric aerosol nucleation.
Main Methods:
- Utilized extensive laboratory measurements of nucleation rates from the CERN CLOUD chamber.
- Included sulfuric acid, ammonia, ions, and organic compounds in the model.
- Compared model simulations with atmospheric observations.
Main Results:
- Nearly all present-day atmospheric nucleation involves sulfuric acid, ammonia, or biogenic organic compounds.
- Ion involvement in nucleation is significant but shows weak dependence on ion concentration.
- Cosmic ray intensity variations have a negligible effect on climate through nucleation.
Conclusions:
- Ammonia and biogenic organic compounds are crucial for atmospheric aerosol formation.
- Ion-induced nucleation plays a role, but its climate impact is limited.
- Current understanding of nucleation processes suggests limited influence of cosmic rays on climate.
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