Author:
Kirkby Jasper,Duplissy Jonathan,Sengupta Kamalika,Frege Carla,Gordon Hamish,Williamson Christina,Heinritzi Martin,Simon Mario,Yan Chao,Almeida João,Tröstl Jasmin,Nieminen Tuomo,Ortega Ismael K.,Wagner Robert,Adamov Alexey,Amorim Antonio,Bernhammer Anne-Kathrin,Bianchi Federico,Breitenlechner Martin,Brilke Sophia,Chen Xuemeng,Craven Jill,Dias Antonio,Ehrhart Sebastian,Flagan Richard C.,Franchin Alessandro,Fuchs Claudia,Guida Roberto,Hakala Jani,Hoyle Christopher R.,Jokinen Tuija,Junninen Heikki,Kangasluoma Juha,Kim Jaeseok,Krapf Manuel,Kürten Andreas,Laaksonen Ari,Lehtipalo Katrianne,Makhmutov Vladimir,Mathot Serge,Molteni Ugo,Onnela Antti,Peräkylä Otso,Piel Felix,Petäjä Tuukka,Praplan Arnaud P.,Pringle Kirsty,Rap Alexandru,Richards Nigel A. D.,Riipinen Ilona,Rissanen Matti P.,Rondo Linda,Sarnela Nina,Schobesberger Siegfried,Scott Catherine E.,Seinfeld John H.,Sipilä Mikko,Steiner Gerhard,Stozhkov Yuri,Stratmann Frank,Tomé Antonio,Virtanen Annele,Vogel Alexander L.,Wagner Andrea C.,Wagner Paul E.,Weingartner Ernest,Wimmer Daniela,Winkler Paul M.,Ye Penglin,Zhang Xuan,Hansel Armin,Dommen Josef,Donahue Neil M.,Worsnop Douglas R.,Baltensperger Urs,Kulmala Markku,Carslaw Kenneth S.,Curtius Joachim
Abstract
AbstractAtmospheric aerosols and their effect on clouds are thought to be important for anthropogenic radiative forcing of the climate, yet remain poorly understood1. Globally, around half of cloud condensation nuclei originate from nucleation of atmospheric vapours2. It is thought that sulfuric acid is essential to initiate most particle formation in the atmosphere3,4, and that ions have a relatively minor role5. Some laboratory studies, however, have reported organic particle formation without the intentional addition of sulfuric acid, although contamination could not be excluded6,7. Here we present evidence for the formation of aerosol particles from highly oxidized biogenic vapours in the absence of sulfuric acid in a large chamber under atmospheric conditions. The highly oxygenated molecules (HOMs) are produced by ozonolysis of α-pinene. We find that ions from Galactic cosmic rays increase the nucleation rate by one to two orders of magnitude compared with neutral nucleation. Our experimental findings are supported by quantum chemical calculations of the cluster binding energies of representative HOMs. Ion-induced nucleation of pure organic particles constitutes a potentially widespread source of aerosol particles in terrestrial environments with low sulfuric acid pollution.
Publisher
Springer Science and Business Media LLC