Atmospheric Radiation Measurement Climate Research Facility US Department of Energy

ccn > Cloud Condensation Nuclei Particle CounterInstrument Type(s) > Baseline • External • Guest

The cloud condensation nuclei counter 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 Derived Measurements


  • Fixed
  • AMF1
  • AMF2
  • AMF3


Mei F, J Wang, S Zhou, Q Zhang, S Collier, and J Xu. 2021. "Measurement report: Cloud condensation nuclei activity and its variation with organic oxidation level and volatility observed during an aerosol life cycle intensive operational period (ALC-IOP)." Atmospheric Chemistry and Physics, 21(17), 10.5194/acp-21-13019-2021.

Kulkarni GR, MS Levin, and JE Shilling. 2021. Cloud Condensation Nuclei Hygroscopicity Value-Added Product Report. Ed. by Robert Stafford, ARM user facility. DOE/SC-ARM-TR-272.

Humphries R, M Keywood, S Gribben, I McRobert, J Ward, P Selleck, S Taylor, J Harnwell, C Flynn, G Kulkarni, G Mace, A Protat, S Alexander, and G McFarquhar. 2021. "Southern Ocean latitudinal gradients of cloud condensation nuclei." Atmospheric Chemistry and Physics, 21(16), 10.5194/acp-21-12757-2021.

Patel P and J Jiang. 2021. "Cloud condensation nuclei characteristics at the Southern Great Plains site: role of particle size distribution and aerosol hygroscopicity." Environmental Research Communications, 3(7), 10.1088/2515-7620/ac0e0b.

Russell LM, D Lubin, I Silber, E Eloranta, J Muelmenstaedt, S Burrows, A Aiken, D Wang, M Petters, M Miller, A Ackerman, A Fridlind, M Witte, M Lebsock, D Painemal, R Chang, J Liggio, and M Wheeler. 2021. Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE) Science Plan. Ed. by Robert Stafford, ARM user facility. DOE/SC-ARM-21-009.

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