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Detailed Reference Information |
Pirjola, L., O'Dowd, C.D. and Kulmala, M. (2002). A model prediction of the yield of cloud condensation nuclei from coastal nucleation events. Journal of Geophysical Research 107: doi: 10.1029/2000JD000213. issn: 0148-0227. |
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The formation and evolution of new particles during coastal nucleation events are examined using the aerosol dynamic and gas-phase chemistry model AEROFOR2. Coastal regions are known to be a strong source of natural aerosol particles and are also strong sources of biogenic vapors which can condense onto aerosol particles, thus resulting in particle growth. A number of model simulations were performed to determine the instantaneous nucleation rate along with the source rate of a generic biogenic vapor leading to the observed particle size distributions which indicate the rapid appearance of ~105--106 cm-3 nucleation mode particles in this environment. Model calculations suggest values of 3 ¿ 105 cm-3 s-1 to 3 ¿ 106 cm-3 s-1 for the instantaneous nucleation rate and a value of 5 ¿ 107 cm-3 s-1 for the condensable vapor source rate in order to reproduce the observed concentrations. A significant fraction of these new particles survive to grow into cloud condensation nuclei (CCN) sizes for supersaturations typically encountered in boundary layer clouds during subsequent evolution over 3 days under clear-sky conditions, thus contributing to the indirect radiative effect of aerosols. The amount of CCN is mainly affected by coagulation between particles and condensation of the biogenic vapor and, to a lesser extent, by condensation of sulphuric acid formed by DMS oxidation. In all simulated cases, an increase of more than 100% in CCN concentration, for supersaturations >0.35% was observed. |
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BACKGROUND DATA FILES |
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Abstract |
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Keywords
Atmospheric Composition and Structure, Aerosols and particles (0345, 4801), Oceanography, Biological and Chemical, Modeling, Atmospheric Composition and Structure, Troposphere--composition and chemistry |
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Publisher
American Geophysical Union 2000 Florida Avenue N.W. Washington, D.C. 20009-1277 USA 1-202-462-6900 1-202-328-0566 service@agu.org |
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