The role of sea-salt emissions and heterogeneous chemistry in the air quality of polluted coastal areas E. Athanasopoulou1, M. Tombrou1, S. N. Pandis2, and A. G. Russell3 1National and Kapodistrian University of Athens, Faculty of Physics, Dept. of Environmental Physics and Meteorology, Athens, Greece 2Dept. of Chemical Engineering, University of Patras, 26500 Patras, Greece 3School of Civil and Environmental Engineering, Georgia Inst. of Technology, 311 Ferst Drive NW, Atlanta, GA 30332-0512, USA
Abstract. Open-ocean and surf-zone sea-salt aerosol (SSA) emission parameterizations
are incorporated in the CAMx aerosol model and applied over an area with an
extended Archipelago (Greece), with a fine grid nested over the highly
populated Attica peninsula. The maximum indirect impact of SSA on PM10
mass (35%) is located over a marine area with moderate SSA production and
elevated shipping emissions (central Aegean Sea) where SSA interacts with
anthropogenic nitric acid forming sodium nitrate. SSA increases PM10
levels in the Athens city center up to 25% during stable onshore winds.
Under such conditions both open-ocean and surf-zone mechanisms contribute to
aerosol production over Attica. A hybrid scheme for gas-to-particle mass
transfer is necessary for accurately simulating semi-volatile aerosol
components when coarse SSA is included. Dynamically simulating mass transfer
to the coarse particles leads to a quadrupling of predicted PM10 nitrate in
the Athens city center and up to two orders of magnitude in its coarse mass
in comparison to using a bulk equilibrium approach.
Citation: Athanasopoulou, E., Tombrou, M., Pandis, S. N., and Russell, A. G.: The role of sea-salt emissions and heterogeneous chemistry in the air quality of polluted coastal areas, Atmos. Chem. Phys., 8, 5755-5769, doi:10.5194/acp-8-5755-2008, 2008.