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Combustion Organic Aerosol As Cloud Condensation Nuclei in Ship Tracks Lynn M University of Rhode Island DigitalCommons@URI Graduate School of Oceanography Faculty Graduate School of Oceanography Publications 2000 Combustion Organic Aerosol as Cloud Condensation Nuclei in Ship Tracks Lynn M. Russell Kevin J. Noone See next page for additional authors Follow this and additional works at: https://digitalcommons.uri.edu/gsofacpubs Terms of Use All rights reserved under copyright. Citation/Publisher Attribution Russell, L.M., K.J. Noone, R.J. Ferek, R.A. Pockalny, R.C. Flagan, and J.H. Seinfeld, 2000: Combustion Organic Aerosol as Cloud Condensation Nuclei in Ship Tracks. J. Atmos. Sci., 57, 2591–2606. doi: 10.1175/1520-0469(2000)0572.0.CO;2. Available at: https://doi.org/10.1175/1520-0469(2000)0572.0.CO;2 This Article is brought to you for free and open access by the Graduate School of Oceanography at DigitalCommons@URI. It has been accepted for inclusion in Graduate School of Oceanography Faculty Publications by an authorized administrator of DigitalCommons@URI. For more information, please contact [email protected]. Authors Lynn M. Russell, Kevin J. Noone, Ronald J. Ferek, Robert Pockalny, Richard C. Flagan, and John H. Seinfeld This article is available at DigitalCommons@URI: https://digitalcommons.uri.edu/gsofacpubs/229 15 AUGUST 2000 RUSSELL ET AL. 2591 Combustion Organic Aerosol as Cloud Condensation Nuclei in Ship Tracks LYNN M. RUSSELL Department of Chemical Engineering, Princeton University, Princeton, New Jersey KEVIN J. NOONE Meteorological Institute, Stockholm University, Stockholm, Sweden RONALD J. FEREK* Department of Atmospheric Sciences, University of Washington, Seattle, Washington ROBERT A. POCKALNY Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island RICHARD C. FLAGAN AND JOHN H. SEINFELD Department of Chemical Engineering, California Institute of Technology, Pasadena, California (Manuscript received 15 May 1996, in ®nal form 7 June 1997) ABSTRACT Polycyclic aromatic hydrocarbons (PAHs) have been sampled in marine stratiform clouds to identify the contribution of anthropogenic combustion emissions in activation of aerosol to cloud droplets. The Monterey Area Ship Track experiment provided an opportunity to acquire data on the role of organic compounds in ambient clouds and in ship tracks identi®ed in satellite images. Identi®cation of PAHs in cloud droplet residual samples indicates that several PAHs are present in cloud condensation nuclei in anthropogenically in¯uenced air and do result in activated droplets in cloud. These results establish the presence of combustion products, such as PAHs, in submicrometer aerosols in anthropogenically in¯uenced marine air, with enhanced concentrations in air polluted by ship ef¯uent. The presence of PAHs in droplet residuals in anthropogenically in¯uenced air masses indicates that some fraction of those combustion products is present in the cloud condensation nuclei that activate in cloud. Although a suf®cient mass of droplet residuals was not collected to establish a similar role for organics from measurements in satellite-identi®ed ship tracks, the available evidence from the fraction of organics present in the interstitial aerosol is consistent with part of the organic fraction partitioning to the droplet population. In addition, the probability that a compound will be found in cloud droplets rather than in the unactivated aerosol and the compound's water solubility are compared. The PAHs studied are only weakly soluble in water, but most of the sparse data collected support more soluble compounds having a higher probability of activation. 1. Introduction pact on cloud droplet number concentration (CDNC) and sizes (National Research Council 1996). To assess The indirect effect of aerosols on climate is based on the importance of the indirect climatic effect of aerosols, the in¯uence of anthropogenic aerosol emissions (or for- it is necessary to relate mass emissions of aerosols and mation of aerosol by gas-to-particle conversion of an- their precursors (such as SO ) to aerosol number con- thropogenic emissions) on the number concentration of 2 centrations, to CCN concentrations (not all particles act cloud condensation nuclei (CCN), with a resulting im- as CCN), to CDNCs, and ®nally to cloud optical prop- erties. An important link in this chain is the CCN prop- erties of anthropogenic aerosols. Whereas the CCN *Current af®liation: Of®ce of Naval Research, Washington, D.C. properties of inorganic sulfate aerosols are reasonably well characterized, those of organic particles emitted from combustion processes are not understood. There Corresponding author address: Dr. Lynn M. Russell, A317 En- gineering Quadrangle, Princeton University, Princeton, NJ 08544. exist neither adequate laboratory studies nor ®eld mea- E-mail: [email protected] surements of the CCN properties of combustion-derived q 2000 American Meteorological Society 2592 JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME 57 TABLE 1. Previous measurements of polycyclic aromatic hydrocarbons, quinones, and ketones in ship and engine emissions, urban areas, and marine aerosol. ND, compound not detected. NR, compound not resolved. Reported concentrationsa Engine emissions Urban Marine (San Fuel oil Diesel (Pasadena) Nicolas) container shipb Gas oil bargeb emissionsc Compound mgm23 mgm23 mgm23 mgm23 mgkm21 Polycyclic aromatic hydrocarbons Anthracene NR ,0.01 0.197 0.7 1.60 Phenanthrene NR ,0.01 8.77 20 12.20 Fluoranthene 0.13 ,0.01 3.89 5.2 13.00 Pyrene 0.17 ,0.01 4.67 5.4 22.60 Benzo[a]¯uorene NR ,0.01 NR NR 1.90 Benzo[b]¯uorene NR ,0.01 1.64 8.5 NR Benz[a]anthracene 0.25 ,0.01 0.249 ,0.009 3.60 Chrysene 0.43 ,0.01 2.572 1.6 9.90 Triphenylene 0.43 ,0.01 5.856 6 NR Benzo[a]pyrene 0.44 ,0.01 0.058 0.03 1.30 Benzo[k]¯uoranthene 0.93 ,0.01 ,0.026 2.8 2.60 Benzo[e]pyrene 1.20 ,0.01 0.057 0.03 2.70 Perylene NR ,0.01 0.896 0.1 1.00 Indeno[1,2,3-cd]pyrene 0.42 ,0.01 0.183 ,0.01 ND Benzo[ghi]perylene 4.43 ,0.01 0.678 ,0.01 1.60 Dibezn[a,h]anthracene NR ,0.01 1.569 ,0.03 ND Polycyclic aromatic ketones and quinones 9H-Fluoren-9-one (¯uorenone) NR ,0.01 NR NR 65.00 9,10-Anthracenedione (anthraquinone) NR ,0.01 NR NR 23.50 9H-Xanthen-9-one (xanthone) NR ,0.01 NR NR 2.70 7H-Benz[de]anthracen-7-one 0.84 ,0.01 NR NR 5.60 a Diesel emission concentrations are reported from Rogge et al. (1993a). b Pasadena ambient and San Nicolas Island ambient concentrations are reported from Rogge et al. (1993c). c Marine vessel emissions are reported from Banisoleiman et al. (1994). Values re¯ect maximum measured during emission trials. carbonaceous aerosols to allow one to predict reliably phase PAHs from marine vessels are between 66 and the effect of such aerosols on cloud droplet activation. 466 metric tons (Banisoleiman et al. 1993). PAH sig- Ship tracks provide an ideal mechanism for studying natures have been found in ambient urban and anthro- effects of anthropogenic emissions on marine strato- pogenically in¯uenced samples (Rogge et al. 1993c). cumulus clouds. The present work provides an initial As noted, the key question for climatic effects is to what investigation of the fate of organic aerosols emitted from extent the anthropogenic organic aerosol mass creates ship exhaust in the marine stratocumulus layer. A major additional CCN. Frisbie and Hudson (1993) and Hudson question is, to what extent can the microphysical fea- (1991) have, in one study, shown that anthropogenic tures of ship tracks be attributed to organic aerosols aerosol increased the concentrations of ef®cient CCN. emitted in the combustion exhaust of ships? Early efforts to speciate the organic fraction of urban There is ample evidence for an organic signature of aerosol were undertaken by Cronn et al. (1977), who combustion products in the aerosol phase of combustion developed a method for using high-resolution mass emissions (Hildemann et al. 1989, 1991; Menichini spectrometry to identify individual organic compounds 1992; Rogge et al. 1993a; Henderson et al. 1984; Ban- in the atmospheric aerosol. Duce et al. (1983) collected isoleiman et al. 1993; J. Tilman 1995, personal com- ®eld samples of marine organic aerosol providing evi- munication). Menichini (1992) has reviewed the use of dence that background oceanic sources contribute ``spy polycyclic aromatic hydrocarbons (PAHs)'' to straight chain alkanes of 9 to 20 carbons, as well as identify emissions of vehicles and coal-burning and in- organic acids. Few other species were found at levels dustrial plants. Banisoleiman et al. (1994) report high exceeding 1 ng m23 in the marine air samples (Duce concentrations of PAHs in the emissions of two fuel and Gagosian 1982; Duce et al. 1983; Schneider et al. oil±powered ships (a ferry and a container ship) and of 1983; Kawamura and Gagosian 1987; Peltzer and Ga- a gas oil±powered barge as summarized in Table 1. gosian 1987). Sicre et al. (1990) have used long-chain Phenanthrene, ¯uoranthene, pyrene, triphenylene, chry- unsaturated ketones in aerosol particles as tracers for sene, and benzo[b]¯uorene appeared in all samples in long-range transport. concentrations exceeding 1 mgm23. Trace amounts of The data of Rogge et al. (1993c) provide an indication benzo[g,h,i]perylene, dibenzo[a,h]anthracene, and in- of the contrast in organic aerosols between background deno[1,2,3-c,d]pyrene were also reported. These authors marine sources at San Nicolas Island 100 miles west of estimate that the total worldwide emissions of aerosol- Los Angeles, California, and urban sources at seven 15 AUGUST 2000 RUSSELL ET AL. 2593 inland sites. The off-coast site showed straight chain lets, which would be consistent with an external mixture alkanes in concentrations of up to 300 ng m23, consistent of hydrophobic and hygroscopic particle populations.
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