Particles, either liquid or solid, or ions upon which condensation of water vapour
(or other substances) begins in the atmosphere. Condensation nuclei are usually very
small hygroscopic aerosols
(
to
in diameter), but these are not as abundant as the smaller particles. The number of
CN
which are active (initiate condensation) in a given air mass may be a function of
the
relative humidity. Usually
CN
are counted as the active nuclei at about 300%
relative humidity, while cloud condensation nuclei
(
CCN)
are counted as the number of active nuclei at
relative humidity less than or equal to 102%.
Source:
PAC, 1990, 62, 2167
(Glossary of atmospheric chemistry terms (Recommendations 1990))
on page 2182
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
https://doi.org/10.1351/goldbook.
