Abstract View
Investigations on Air Ion Properties and Their Connections to Atmospheric Radioactivity and Electricity
XUEMENG CHEN, Heikki Junninen, Jussi Paatero, Susana Barbosa, Joonas Vanhanen, Tuukka Petäjä, Veli-Matti Kerminen, Markku Kulmala, Carlos Larriba-Andaluz, University of Tartu / IUPUI
Abstract Number: 289
Working Group: Aerosol Physics
Abstract
Air ions refer to airborne charge carriers present in air. These range from small molecules (<1nm) to clusters (1-3nm) to nanoparticles (>3nm). Their production is closely related to ionization processes caused by atmospheric radioactivity, including radon, cosmic and terrestrial radiation1. Air ions are a fundamental player in atmospheric electricity. Being the charge carriers, air ions respond to the Earth-atmosphere electric field by drifting towards different directions depending on their polarities. Air ions (in particular molecules and clusters) are also observed frequently taking part in atmospheric new particle formation (NPF)2-3, through which they modify atmospheric aerosol properties. Atmospheric aerosol particles can impact air quality, weather and climate. Via cloud processes and space charge formation, aerosol particles can also interact with atmospheric electricity and radioactivity4-5. Moreover, many aerosol measurement techniques are based on pre-charging of sampled particles. Therefore, it is crucial to have a thorough knowledge of ion properties to link all these disciplines. The connections of air ions to atmospheric electricity and radioactivity will be presented based on ambient measurements conducted in Finland and Estonia. We will also introduce a new Marie-Curie project —MaSMob-Lion, where we investigate the mass-size-mobility relationship of ions aiming to facilitate a smooth interconversion of the three properties to assist intercomparisons of ions and aerosol particles measured by different techniques.
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[3] Jokinen, T., et al., Science Advances, 2018. 4(11): p. eaat9744.
[4] Bennett, A.J. and R.G. Harrison, Weather, 2007. 62(10): p. 277-283.
[5] Paatero, J. and J. Hatakka, Boreal Env. Res., 1999. 4: p. 285-293.