Causes and importance of new particle formation in the present‐day and preindustrial atmospheres

作者：Hamish Gordon, J. Kirkby, Urs Baltensperger, Federico Bianchi, Martin Breitenlechner, Joachim Curtius, António Dias, Josef Dommen, Neil M. Donahue, E. M. Dunne, Jonathan Duplissy, Sebastian Ehrhart, Richard C. Flagan, Carla Frege, Claudia Fuchs, Armin Hansel, C. R. Hoyle, Markku Kulmala, Andreas Kürten, Katrianne Lehtipalo, В. С. Махмутов, Ugo Molteni, Matti Rissanen, Yuri Stozkhov, Jasmin Tröstl, Georgios Tsagkogeorgas, Robert Wagner, Christina Williamson, Daniela Wimmer, Paul M. Winkler, Chao Yan, K. S. Carslaw · 发表于：Journal of Geophysical Research Atmospheres · 年份：2017 · DOI：10.1002/2017jd026844 · 被引用次数：537 · 研究领域：Atmospheric chemistry and aerosols、Atmospheric aerosols and clouds、Atmospheric Ozone and Climate

Abstract New particle formation has been estimated to produce around half of cloud‐forming particles in the present‐day atmosphere, via gas‐to‐particle conversion. Here we assess the importance of new particle formation (NPF) for both the present‐day and the preindustrial atmospheres. We use a global aerosol model with parametrizations of NPF from previously published CLOUD chamber experiments involving sulfuric acid, ammonia, organic molecules, and ions. We find that NPF produces around 67% of cloud condensation nuclei at 0.2% supersaturation (CCN0.2%) at the level of low clouds in the preindustrial atmosphere (estimated uncertainty range 45–84%) and 54% in the present day (estimated uncertainty range 38–66%). Concerning causes, we find that the importance of biogenic volatile organic compounds (BVOCs) in NPF and CCN formation is greater than previously thought. Removing BVOCs and hence all secondary organic aerosol from our model reduces low‐cloud‐level CCN concentrations at 0.2% supersaturation by 26% in the present‐day atmosphere and 41% in the preindustrial. Around three quarters of this reduction is due to the tiny fraction of the oxidation products of BVOCs that have sufficiently low volatility to be involved in NPF and early growth. Furthermore, we estimate that 40% of preindustrial CCN0.2% are formed via ion‐induced NPF, compared with 27% in the present day, although we caution that the ion‐induced fraction of NPF involving BVOCs is poorly measured at present. Our mo...