Havala Olson Taylor Pye¹, Athanasios Nenes², Becky Alexander³, Andrew P Ault⁴, Mary C Barth⁵, Simon L Clegg⁶, Jeffrey Lee Collett Jr⁷, Kathleen Fahey^8,9, Christopher J Hennigan¹⁰, Hartmut Herrmann¹¹, Maria Kanakidou¹², James Kelly¹³, I-Ting Ku¹⁴, V Faye McNeill¹⁵, Nicole Riemer¹⁶, Thomas Schaefer¹⁷, Guoliang Shi¹⁸, Andreas Tilgner¹⁷, John T Walker¹⁹, Tao Wang²⁰, Rodney J Weber²¹, Jia Xing²², Rahul A Zaveri²³ and Andreas Zuend²⁴, (1)US Environmental Protection Agency Research Triangle Park, Durham, NC, United States, (2)Ecole Polytechnique Federale de Lausanne, School of Architecture, Civil and Environmental Engineering (ENAC), Laboratory of Atmospheric Processes and their Impacts (LAPI), Lausanne, Switzerland, (3)University of Washington, Department of Atmospheric Sciences, Seattle, WA, United States, (4)University of Michigan Ann Arbor, Department of Chemistry, Ann Arbor, MI, United States, (5)Natl Ctr Atmospheric Research, Boulder, CO, United States, (6)University of East Anglia, Norwich, United Kingdom, (7)Colorado State University, Atmospheric Science, Fort Collins, CO, United States, (8)West Sussex, United Kingdom, (9)U.S. EPA, Rtp, United States, (10)University of Maryland, Baltimore County, Baltimore, MD, United States, (11)Leibniz Institute for Tropospheric Research (TROPOS), Atmospheric Chemistry Department (ACD), Leipzig, Germany, (12)Environmental Chemical Processes Laboratory, Department of Chemistry, University of Crete, Heraklion, Greece, (13)Environmental Protection Agency Research Triangle Park, Research Triangle Park, NC, United States, (14)Colorado State University, Fort Collins, United States, (15)Columbia University of New York, Palisades, NY, United States, (16)University of Illinois at Urbana-Champaign, Department of Atmospheric Sciences, Urbana, IL, United States, (17)Leibniz Institute for Tropospheric Research, Leipzig, Germany, (18)Nankai University, Tianjin, China, (19)United States Environmental Protection Agency, Office of Research and Development, Research Triangle Park, NC, United States, (20)Hong Kong Polytechnic University, Department of Civil and Environmental Engineering, Hong Kong, China, (21)Georgia Institute of Technology, School of Earth and Atmospheric Sciences, Atlanta, GA, United States, (22)State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing, China, (23)Pacific Northwest Natl Lab, Richland, WA, United States, (24)McGill University, Department of Atmospheric and Oceanic Sciences, Montreal, QC, Canada