Growth of nucleation mode particles in the summertime Arctic: a case study

• Published in: Atmospheric Chemistry and Physics
• Main Authors: Willis, Megan D., Burkart, Julia, Thomas, Jennie L., Köllner, Franziska, Schneider, Johannes, Bozem, Heiko, Hoor, Peter M., Aliabadi, Amir A., Schulz, Hannes, Herber, Andreas B., Leaitch, W. Richard, Abbatt, Jonathan P. D.
• Other Authors: Department of Chemistry University of Toronto, University of Toronto, TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Chemistry (MPIC), Max-Planck-Gesellschaft, Johannes Gutenberg - Universität Mainz = Johannes Gutenberg University (JGU), Environment and Climate Change Canada, Massachusetts Institute of Technology (MIT), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung = Alfred Wegener Institute for Polar and Marine Research = Institut Alfred-Wegener pour la recherche polaire et marine (AWI), Helmholtz-Gemeinschaft = Helmholtz Association, Natural Sciences and Engineering Research Council of Canada, The Alfred Wegener Institute and Environment and Climate Change Canada
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; Aitken; Arctic; black carbon
• Online Access: https://insu.hal.science/insu-01336721; https://insu.hal.science/insu-01336721/document; https://insu.hal.science/insu-01336721/file/acp-16-7663-2016.pdf; https://doi.org/10.5194/acp-16-7663-2016

International audience The summertime Arctic lower troposphere is a relatively pristine background aerosol environment dominated by nucleation and Aitken mode particles. Understanding the mechanisms that control the formation and growth of aerosol is crucial for our ability to predict cloud properties and therefore radiative balance and climate. We present an analysis of an aerosol growth event observed in the Canadian Arc-tic Archipelago during summer as part of the NETCARE project. Under stable and clean atmospheric conditions, with low inversion heights, carbon monoxide less than 80 ppb v , and black carbon less than 5 ng m −3 , we observe growth of small particles, < 20 nm in diameter, into sizes above 50 nm. Aerosol growth was correlated with the presence of organic species, trimethylamine, and methanesulfonic acid (MSA) in particles ∼ 80 nm and larger, where the organ-ics are similar to those previously observed in marine settings. MSA-to-sulfate ratios as high as 0.15 were observed during aerosol growth, suggesting an important marine influence. The organic-rich aerosol contributes significantly to particles active as cloud condensation nuclei (CCN, su-persaturation = 0.6 %), which are elevated in concentration during aerosol growth above background levels of ∼ 100 to ∼ 220 cm −3. Results from this case study highlight the potential importance of secondary organic aerosol formation and its role in growing nucleation mode aerosol into CCN-active sizes in this remote marine environment.