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Updated: Jul 16, 2026

Production and Measurement of Organic Particulate Matter in the Harvard Environmental Chamber
Published on: November 18, 2018
Aerosol formation: atmospheric particles from organic vapours
Colin D O'Dowd1, Pasi Aalto, Kaarle Hmeri
1Division of Atmospheric Sciences, Department of Physical Sciences, PO Box 64, University of Helsinki, 00014 Helsinki, Finland. colin.odowd@cmas.demon.co.uk
Abstract:
Aerosol particles produced over forested areas may affect climate by acting as nuclei for cloud condensation, but their composition (and hence the chemical species that drive their production) remains an open question. Here we show, to our knowledge for the first time, that these newly formed particles (3-5 nm in diameter) are composed primarily of organic species, such as cis-pinonic acid and pinic acid, produced by oxidation of terpenes in organic vapours released from the canopy.
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