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CCN
Cloud Condensation Nuclei Particle Counter
Baseline Instrument, External Instrument, Guest
The cloud condensation nuclei counter (CCN) measures the concentration of aerosol particles by drawing an air sample through a column with thermodynamically unstable supersaturated water vapor that can condense onto aerosol particles. Particles that are activated, i.e., grown larger in the process, are counted and sized by an optical particle counter (OPC). In this way the CCN measures activated ambient aerosol particle number concentration as a function of supersaturation.
ARM operates both one- and two-column versions of the CCN.
Primary Measurements
Contact
View all contacts-
Ogochukwu EnekwizuLead Mentor Brookhaven National Laboratory
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Elisabeth AndrewsLead Mentor: NSA University of Colorado
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Melita KeywoodExternal Data Contact: KCG Centre for Australian Weather and Climate Research
Related Data Announcements
References
View all references- Mayol-Bracero et al. ARM FY2025 Aerosol Operations Plan. 2025. 10.2172/2482516.
- Uin et al. Cloud Condensation Nuclei Particle Counter Instrument Handbook. 2024. 10.2172/1251411.
Locations
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Atmospheric Radiation Measurement (ARM) | Reviewed
March 2025