Modelling the contribution of biogenic volatile organic compounds to new particle formation in the Julich plant atmosphere chamber

• Main Authors: Roldin, P., Liao, L., Mogensen, D., Dal Maso, M., Rusanen, A., Kerminen, V. -M., Mentel, T. F., Wildt, J., Kleist, E., Kiendler-Scharr, A., Tillmann, R., Ehn, M., Kulmala, Markku, Boy, M.
• Other Authors: Department of Physics, Ecosystem processes (INAR Forest Sciences), Aerosol-Cloud-Climate -Interactions (ACCI)
• Format: Article in Journal/Newspaper
• Language: English
• Published: COPERNICUS GESELLSCHAFT MBH 2016
• Subjects: SULFURIC-ACID CONCENTRATION; AEROSOL WALL LOSSES; TROPOSPHERIC DEGRADATION; ACTIVITY-COEFFICIENTS; THERMODYNAMIC MODEL; OXIDATION-PRODUCTS; NUCLEATION; EMISSIONS; GAS; GROWTH; 114 Physical sciences; Arctic; The Cryosphere
• Online Access: http://hdl.handle.net/10138/161734

We used the Aerosol Dynamics gas- and particle-phase chemistry model for laboratory CHAMber studies (ADCHAM) to simulate the contribution of BVOC plant emissions to the observed new particle formation during photooxidation experiments performed in the Julich Plant-Atmosphere Chamber and to evaluate how well smog chamber experiments can mimic the atmospheric conditions during new particle formation events. ADCHAM couples the detailed gas-phase chemistry from Master Chemical Mechanism with a novel aerosol dynamics and particle phase chemistry module. Our model simulations reveal that the observed particle growth may have either been controlled by the formation rate of semi- and low-volatility organic compounds in the gas phase or by acid catalysed heterogeneous reactions between semi-volatility organic compounds in the particle surface layer (e.g. peroxyhemiacetal dimer formation). The contribution of extremely low-volatility organic gas-phase compounds to the particle formation and growth was suppressed because of their rapid and irreversible wall losses, which decreased their contribution to the nano-CN formation and growth compared to the atmospheric situation. The best agreement between the modelled and measured total particle number concentration (R-2 > 0.95) was achieved if the nano-CN was formed by kinetic nucleation involving both sulphuric acid and organic compounds formed from OH oxidation of BVOCs. Peer reviewed