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614674 
Journal Article 
Comprehensive Simultaneous Shipboard and Airborne Characterization of Exhaust from a Modern Container Ship at Sea 
Murphy, SM; Acrawal, H; Sorooshian, A; Padró, LT; Gates, H; Hersey, S; Welch, WA; Lung, H; Miller, JW; Cocker, DRIII; Nenes, A; Jonsson, HH; Flagan, RC; Seinfeld, JH 
2009 
1 
Environmental Science & Technology
ISSN: 0013-936X
EISSN: 1520-5851 
43 
13 
4626-4640 
English 
19673244 
WOS:000267435500006 
We report the first joint shipboard and airborne study focused on the chemical composition and water-uptake behavior of particulate ship emissions. The study focuses on emissions from the main propulsion engine of a Post-Panamax class container ship cruising off the central coast of California and horning heavy fuel oil. Shipboard sampling included micro-orifice uniform deposit impactors (MOUDI) with subsequent offline analysis, whereas airborne measurements involved a number of real-time analyzers to characterize the plume aerosol, aged from a few seconds to over an hour. The mass ratio of particulate organic carbon to sulfate at the base of the ship stack was 0.23 ± 0.03, and increased to 0.30 ± 0.01 in the airborne exhaust plume, with the additional organic mass in the airborne plume being concentrated largely in particles below 100 nm in diameter. The organic to sulfate mass ratio in the exhaust aerosol remained constant during the first hour of plume dilution into the marine boundary layer. The mono spectrum of the organic fraction of the exhaust aerosol strongly resembles that of emissions from other diesel sources and appears to be predominantly hydrocarbon-like organic (HOA) material. Background aerosol which, based on air mass hack trajectories, probably consisted of aged ship emissions and marine aerosol, contained a lower organic mass fraction than the fresh plume and had a much more oxidized organic component A volume-weighted mixing rule is able to accurately predict hygroscopic growth factors in the background aerosol but measured and calculated growth factors do not agree for aerosols in the ship exhaust plume. Calculated CCN concentrations, at supersaturations ranging from 0.1 to 0.33%, agree well with measurements in the ship-exhaust plume. Using size-resolved chemical composition instead of hulk submicrometer composition baa little effect on the predicted CCN concentrations because the cutoff diameter for CCN activation is larger than the diameter where the mass fraction of organic aerosol begins to increase significantly. The particle number emission factor estimated from this study is 1.3 × 1015 (kg fuel)-1, with less than 1/10 of the particles having diameters above 100 nm; 24% of particles (>10 nm in diamecer) activate into cloud droplets at - 03% supersaturation. [ABSTRACT FROM AUTHOR] Copyright of Environmental Science & Technology is the property of American Chemical Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) 
CONTAINER ships; SHIPS; ENVIRONMENTAL aspects; AIR -- Pollution -- Research; AIR -- Pollution; PARTICULATE matter; EMISSIONS; AEROSOLS -- Environmental aspects; SULFATES