Factors controlling the evaporation of secondary organic aerosol from α‐pinene ozonolysis. Issue 5 (6th March 2017)

• Record Type: Journal Article
• Authors: Yli‐Juuti, Taina; Pajunoja, Aki; Tikkanen, Olli‐Pekka; Buchholz, Angela; Faiola, Celia; Väisänen, Olli; Hao, Liqing; Kari, Eetu; Peräkylä, Otso; Garmash, Olga; Shiraiwa, Manabu; Ehn, Mikael; Lehtinen, Kari; Virtanen, Annele
• Is Part Of: Geophysical research letters. Volume 44:Issue 5(2017)
• Page Start: 2562
• Page End: 2570
• Publication Date: 2017-03-06
• Subjects: SOA -- α‐pinene -- volatility -- viscosity -- VBS; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2016GL072364
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Secondary organic aerosols (SOA) forms a major fraction of organic aerosols in the atmosphere. Knowledge of SOA properties that affect their dynamics in the atmosphere is needed for improving climate models. By combining experimental and modeling techniques, we investigated the factors controlling SOA evaporation under different humidity conditions. Our experiments support the conclusion of particle phase diffusivity limiting the evaporation under dry conditions. Viscosity of particles at dry conditions was estimated to increase several orders of magnitude during evaporation, up to 10 9 Pa s. However, at atmospherically relevant relative humidity and time scales, our results show that diffusion limitations may have a minor effect on evaporation of the studied α‐pinene SOA particles. Based on previous studies and our model simulations, we suggest that, in warm environments dominated by biogenic emissions, the major uncertainty in models describing the SOA particle evaporation is related to the volatility of SOA constituents. Key Points: Evaporation of secondary organic aerosol from α‐pinene ozonolysis was studied under different relative humidity At dry conditions the evaporation was likely slowed down by diffusion limitations resulting from viscosity of the particles At atmospherically relevant relative humidity, diffusion limitations had a minor effect on evaporation of the particles