| Abstract
Ozone, particulate matter less than 2.5 μm in size (PM2.5) and other pollutants either
organic or inorganic are subjected to a complex series of common emissions, physical and
chemical transformations. Consequently improving air quality requires understanding of how
the emissions reductions of one pollutant can lead to changes in the concentration of other
pollutants. Three-dimensional chemical transport models that can accurately and efficiently
describe the physical and chemical transformations of gas and aerosol species can estimate
these source-receptor relations.
PMCAMx-2008 [1, 2, 3], a detailed 3-D chemical transport model (CTM), was applied to
Europe in order to simulate the mass concentration and chemical composition of particulate
matter during May 2008 and February 2009. The model includes a state-of-the-art organic
aerosol module which is based on the volatility basis set framework [4, 5] treating both
primary and secondary organic components to be semivolatile and photochemically reactive.
The model performance was evaluated against high time resolution aerosol mass
spectrometer (AMS) measurements taken from various sites in Europe during the
EUCAARI intensive periods [6]. The ability of PMCAMx to predict hourly average
concentrations of the major PM2.5components against AMS measurements in Europe is
encouraging.
Sensitivity analyses were conducted in order to quantify the changes in fine aerosol
(PM2.5) mass concentrations in response to different emission reductions. Five separate
emissions scenarios were applied and the effects of 50% reduction of gaseous emissions
(sulfur dioxide (SO2), ammonia (NH3), oxides of nitrogen (NOx), anthropogenic volatile
organic compounds (VOCs)), as well as 50% decrease of anthropogenic primary OA
emissions on the concentration of the major PM2.5 components (sulfate, ammonium, nitrate,
and organics) was investigated.
References
[1].Karydis, V.A., Tsimpidi, A.P., Fountoukis, C., Nenes, A., Zavala, M., Lei, W., Molina,
L.T., Pandis, S.N., Atmos. Environ., 44, 608-620, 2010.
[2].Tsimpidi, A.P., Karydis, V.A., Zavala, M., Lei, W., Molina, L.T., Ulbrich,
I.M.,
Jimenez, J. L., and Pandis, S.N., Atmos. Chem. Phys., 10, 525–546, 2010.
[3].Murphy, B.N., and Pandis, S.N., Environ. Sci. Technol., 43, 4722–4728,
2009.
[4].Stanier, C.O., Donahue, N.M., and Pandis, S.N., Atmos. Environ., 42, 2276–2299,
2008.
[5].Donahue, N.M., Robinson, A.L., Stanier, C.O., and Pandis, S.N., Environ. Sci.
Technol., 40, 2635–2643, 2006.
[6].Fountoukis, C., Racherla, P.N., Polymeneas, P., Haralabidis, P.E., Pilinis, C. and
Pandis, S.N., ACP, submitted. |