Open Access

Dominik Stolzenburg, Lukas Fischer, Alexander L. Vogel, Martin Heinritzi, Meredith Schervish, Mario Simon, Andrea Christine Wagner, Lubna Dada, Lauri R. Ahonen, Antonio Amorim, Andrea Baccarini, Paulus Salomon Bauer, Bernhard Baumgartner, Anton Bergen, Federico Bianchi, Martin Breitenlechner, Sophia Brilke, Stephany Buenrostro Mazon, Dexian Chen, Antonio Dias, Danielle C. Draper, Jonathan Duplissy, Imad El Haddad, Henning Finkenzeller, Carla Frege, Claudia Fuchs, Olga Garmash, Hamish Gordon, Xucheng He, Johanna Helm, Victoria Hofbauer, Christopher Robert Hoyle, Changhyuk Kim, Jasper Kirkby, Jenni Kontkanen, Christoph Andreas Kürten, Janne Lampilahti, Michael Joseph Lawler, Katrianne Lehtipalo, Markus Leiminger, Huajun Mai, Serge Mathot, Bernhard Mentler, Ugo Molteni, Wei Nie, Tuomo Nieminen, John B. Nowak, Andrea Ojdanic, Antti Onnela, Monica Passananti, Tuukka Petäjä, Lauriane L. J. Quéléver, Matti P. Rissanen, Nina Sarnela, Simon Schallhart, Christian Tauber, Antonio Tomé, Robert Wagner, Mingyi Wang, Lena Weitz, Daniela Wimmer, Mao Xiao, Chao Yan, Penglin Ye, Qiaozhi Zha, Urs Baltensperger, Joachim Curtius, Josef Dommen, Richard C. Flagan, Markku Kulmala, James N. Smith, Douglas R. Worsnop, Armin Hansel, Neil McPherson Donahue, Paul M. Winkler

• Nucleation and growth of aerosol particles from atmospheric vapors constitutes a major source of global cloud condensation nuclei (CCN). The fraction of newly formed particles that reaches CCN sizes is highly sensitive to particle growth rates, especially for particle sizes <10 nm, where coagulation losses to larger aerosol particles are greatest. Recent results show that some oxidation products from biogenic volatile organic compounds are major contributors to particle formation and initial growth. However, whether oxidized organics contribute to particle growth over the broad span of tropospheric temperatures remains an open question, and quantitative mass balance for organic growth has yet to be demonstrated at any temperature. Here, in experiments performed under atmospheric conditions in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at the European Organization for Nuclear Research (CERN), we show that rapid growth of organic particles occurs over the range from −25 ∘C to 25 ∘C. The lower extent of autoxidation at reduced temperatures is compensated by the decreased volatility of all oxidized molecules. This is confirmed by particle-phase composition measurements, showing enhanced uptake of relatively less oxygenated products at cold temperatures. We can reproduce the measured growth rates using an aerosol growth model based entirely on the experimentally measured gas-phase spectra of oxidized organic molecules obtained from two complementary mass spectrometers. We show that the growth rates are sensitive to particle curvature, explaining widespread atmospheric observations that particle growth rates increase in the single-digit-nanometer size range. Our results demonstrate that organic vapors can contribute to particle growth over a wide range of tropospheric temperatures from molecular cluster sizes onward.