ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-8-5489-2008 Comprehensive airborne characterization of aerosol from a major bovine source Sorooshian A. 1 6 Murphy S. M. 1 Hersey S. 1 Gates H. 1 Padro L. T. 2 Nenes A. 2 3 Brechtel F. J. 1 4 Jonsson H. 5 Flagan R. C. 1 Seinfeld J. H. 1 Departments of Environmental Science and Engineering and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA Brechtel Manufacturing Inc., Hayward, CA, USA Center for Interdisciplinary Remotely-Piloted Aircraft Studies, Naval Postgraduate School, Monterey, CA, USA now at: Cooperative Inst. for Research in the Atmosphere (CIRA), Colorado State University, Fort Collins, CO, USA 12 09 2008 8 17 5489 5520 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/8/5489/2008/acp-8-5489-2008.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/8/5489/2008/acp-8-5489-2008.pdf

We report an extensive airborne characterization of aerosol downwind of a massive bovine source in the San Joaquin Valley (California) on two flights during July 2007. The Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter probed chemical composition, particle size distribution, mixing state, sub- and supersaturated water uptake behavior, light scattering properties, and the interrelationship between these parameters and meteorology. Total PM<sub>1.0</sub> levels and concentrations of organics, nitrate, and ammonium were enhanced in the plume from the source as compared to the background aerosol. Organics dominated the plume aerosol mass (~56–64%), followed either by sulfate or nitrate, and then ammonium. Particulate amines were detected in the plume aerosol by a particle-into-liquid sampler (PILS) and via mass spectral markers in the Aerodyne C-ToF-AMS. Amines were found to be a significant atmospheric base even in the presence of ammonia; particulate amine concentrations are estimated as at least 14–23% of that of ammonium in the plume. Enhanced sub- and supersaturated water uptake and reduced refractive indices were coincident with lower organic mass fractions, higher nitrate mass fractions, and the detection of amines. The likelihood of suppressed droplet growth owing to kinetic limitations from hydrophobic organic material is explored. After removing effects associated with size distribution and mixing state, the normalized activated fraction of cloud condensation nuclei (CCN) increased as a function of the subsaturated hygroscopic growth factor, with the highest activated fractions being consistent with relatively lower organic mass fractions and higher nitrate mass fractions. Subsaturated hygroscopic growth factors for the organic fraction of the aerosol are estimated based on employing the Zdanovskii-Stokes Robinson (ZSR) mixing rule. Representative values for a parameterization treating particle water uptake in both the sub- and supersaturated regimes are reported for incorporation into atmospheric models.

 References Abalos, M., Bayona, J M., and Ventura, F.: Development of a solid-phase microextraction GC-NPD procedure for the determination of free volatile amines in wastewater and sewage-polluted waters, Anal. Chem., 71, 3531–3537, 1999. Aiken, A C., Decarlo, P F., Kroll, J H., Worsnop, D R., Huffman, J A., Docherty, K S., Ulbrich, I M., Mohr, C., Kimmel, J R., Sueper, D., Sun, Y., Zhang, Q., Trimborn, A., Northway, M., Ziemann, P J., Canagaratna, M R., Onasch, T B., Alfarra, M R., Prevot, A S H., Dommen, J., Duplissy, J., Metzger, A., Baltensperger, U., and Jimenez, J L.: O/C and OM/OC ratios of primary, secondary, and ambient organic aerosols with high-resolution time-of-flight aerosol mass spectrometry, Environ. Sci. Technol., 42, 4478–4485, 2008. Aklilu, Y., Mozurkewich, M., Prenni, A J., Kreidenweis, S M., Alfarra, M R., Allan, J D., Anlauf, K., Brook, J., Leaitch, W R., Sharma, S., Boudries, H., and Worsnop, D R.: Hygroscopicity of particles at two rural, urban influenced sites during Pacific 2001: Comparison with estimates of water uptake from particle composition, Atmos. Environ., 40, 2650–2661, 2006. Alfarra, M R., Coe, H., Allan, J D., Bower, K N., Boudries, H., Canagaratna, M R., Jimenez, J L., Jayne, J T., Garforth, A A., Li, S M., and Worsnop, D R.: Characterization of urban and rural organic particulate in the lower Fraser valley using two aerodyne aerosol mass spectrometers, Atmos. Environ., 38, 5745–5758, 2004. Allan, J D., Delia, A E., Coe, H., Bower, K N., Alfarra, M R., Jimenez, J L., Middlebrook, A M., Drewnick, F., Onasch, T B., Canagaratna, M R., Jayne, J T., and Worsnop, D R.: A generalised method for the extraction of chemically resolved mass spectra from aerodyne aerosol mass spectrometer data, J. Aerosol Sci., 35, 909–922, 2004. Anderson, N., Strader, R., and Davidson, C.: Airborne reduced nitrogen: ammonia emissions from agriculture and other sources, Environ. Int., 29, 277–286, 2003. Angelino, S., Suess, D T., and Prather, K A.: Formation of aerosol particles from reactions of secondary and tertiary alkylamines: Characterization by aerosol time-of-flight mass spectrometry, Environ. Sci. Technol., 35, 3130–3138, 2001. Apsimon, H M., Kruse, M., and Bell, J N B.: Ammonia emissions and their role in acid deposition, Atmos. Environ., 21, 1939–1946, 1987. Asa-Awuku, A. and Nenes, A.: Effect of solute dissolution kinetics on cloud droplet formation: Extended Kohler theory, J. Geophys. Res., 112, D22201, doi:10.1029/2005JD006934, 2007. Asman, W A H. and Janssen, A J.: A long-range transport model for ammonia and ammonium for Europe, Atmos. Environ., 21, 2099–2119, 1987. Battye, W., Aneja, V P., and Roelle, P A.: Evaluation and improvement of ammonia emissions inventories, Atmos. Environ., 37, 3873–3883, 2003. Beddows, D C S., Donovan, R J., Harrison, R M., Heal, M R., Kinnersley, R P., King, M D., Nicholson, D H., and Thompson, K C.: Correlations in the chemical composition of rural background atmospheric aerosol in the UK determined in real time using time-of-flight mass spectrometry, J. Environ. Monitor., 6, 124–133, 2004. Blanchard, C L., Roth, P M., Tanenbaum, S J., Ziman, S D., and Seinfeld, J H.: The use of ambient measurements to identify which precursor species limit aerosol nitrate formation, J. Air Waste Manage., 50, 2073–2084, 2000. Brechtel, F J. and Kreidenweis, S M.: Predicting particle critical supersaturation from hygroscopic growth measurements in the humidified TDMA. part I: Theory and sensitivity studies, J. Atmos. Sci., 57, 1854–1871, 2000. Cadle, S H. and Mulawa, P A.: Low-molecular weight aliphatic-amines in exhaust from catalyst-equipped cars, Environ. Sci. Technol., 14, 718–723, 1980. Choi, M Y. and Chan, C K.: The effects of organic species on the hygroscopic behaviors of inorganic aerosols, Environ. Sci. Technol., 36, 2422–2428, 2002a. Choi, M Y. and Chan, C K.: Continuous measurements of the water activities of aqueous droplets of water-soluble organic compounds, J. Phys. Chem. A, 106, 4566–4572, 2002b. Chow, J C., Watson, J G., Lu, Z Q., Lowenthal, D H., Frazier, C A., Solomon, P A., Thuillier, R H., and Magliano, K.: Descriptive analysis of PM(2.5) and PM(10) at regionally representative locations during SJVAQS/AUSPEX, Atmos. Environ., 30, 2079–2112, 1996. Chow, J C., Chen, L W A., Watson, J G., Lowenthal, D H., Magliano, K A., Turkiewicz, K., and Lehrman, D E.: PM2.5 chemical composition and spatiotemporal variability during the California Regional PM10/PM2.5 Air Quality Study (CRPAQS), J. Geophys. Res., 111, D10S04, doi:10.1029/2005JD006457, 2006. Chuang, P Y.: Measurement of the timescale of hygroscopic growth for atmospheric aerosols, J. Geophys. Res., 108, 4282, doi:10.1029/2002JD002757, 2003. Clegg, S L., Brimblecombe, P., and Wexler, A S.: Thermodynamic model of the system H+-NH4+-Na+-SO42–NO3–Cl–H2O at 298.15 K, J. Phys. Chem. A, 102, 2155–2171, 1998. Clegg, S L., Seinfeld, J H., and Edney, E O.: Thermodynamic modelling of aqueous aerosols containing electrolytes and dissolved organic compounds. II. An extended Zdanovskii-Stokes-Robinson approach, J. Aerosol Sci., 34, 667–690, 2003. Clegg, S L. and Seinfeld, J H.: Improvement of the Zdanovskii-Stokes-Robinson model for mixtures containing solutes of different charge types, J. Phys. Chem. A, 108, 1008–1017, 2004. Clegg, S L. and Seinfeld, J H.: Thermodynamic models of aqueous solutions containing inorganic electrolytes and dicarboxylic acids at 298.15 K. 1. The acids as nondissociating components, J. Phys. Chem. A, 110, 5692–5717, 2006a. Clegg, S L. and Seinfeld, J H.: Thermodynamic models of aqueous solutions containing inorganic electrolytes and dicarboxylic acids at 298.15 K. 2. Systems including dissociation equilibria, J. Phys. Chem. A, 110, 5718–5734, 2006b. Cruz, C N. and Pandis, S N.: Deliquescence and hygroscopic growth of mixed inorganic-organic atmospheric aerosol, Environ. Sci. Technol., 34, 4313–4319, 2000. Cubison, M J., Alfarra, M R., Allan, J., Bower, K N., Coe, H., McFiggans, G B., Whitehead, J D., Williams, P I., Zhang, Q., Jimenez, J L., Hopkins, J., and Lee, J.: The characterisation of pollution aerosol in a changing photochemical environment, Atmos. Chem. Phys., 6, 5573–5588, 2006 Dean, J A.: Lange's Handbook of Chemistry, Fifteenth Edition, McGraw-Hill, 1999. Denkenberger, K A., Moffet, R C., Holecek, J C., Rebotier, T P., and Prather, K A.: Real-time, single-particle measurements of oligomers in aged ambient aerosol particles, Environ. Sci. Technol., 41, 5439–5446, 2007. Dick, W D., Saxena, P., and McMurry, P H.: Estimation of water uptake by organic compounds in submicron aerosols measured during the Southeastern Aerosol and Visibility Study, J. Geophys. Res., 105, 1471–1479, 2000. Dillner, A M., Stein, C., Larson, S M., and Hitzenberger, R.: Measuring the mass extinction efficiency of elemental carbon in rural aerosol, Aerosol Sci. Tech., 35, 1009–1021, 2001. Dinar, E., Anttila, T., and Rudich, Y.: CCN activity and hygroscopic growth of organic aerosols following reactive uptake of ammonia, Environ. Sci. Technol., 42, 793–799, 2008. Doyle, G J., Tuazon, E C., Graham, R A., Mischke, T M., Winer, A M., and Pitts, J N.: Simultaneous concentrations of ammonia and nitric-acid in a polluted atmosphere and their equilibrium relationship to particulate ammonium-nitrate, Environ. Sci. Technol., 13, 1416–1419, 1979. Draxler, R R. and Rolph, G D.: HYSPLIT (HYbrid Single-Particle Lagrangian Integrated Trajectory) Model access via NOAA ARL READY Website (http://www.arl.noaa.gov/ready/hysplit4.html), NOAA Air Resources Laboratory, Silver Spring, MD, 2003. Drewnick, F., Hings, S S., DeCarlo, P., Jayne, J T., Gonin, M., Fuhrer, K., Weimer, S., Jimenez, J L., Demerjian, K L., Borrmann, S., and Worsnop, D R.: A new time-of-flight aerosol mass spectrometer (tof-ams) – instrument description and first field deployment, Aerosol Sci. Tech., 39, 637–658, 2005. Dusek, U., Frank, G P., Hildebrandt, L., Curtius, J., Schneider, J., Walter, S., Chand, D., Drewnick, F., Hings, S., Jung, D., Borrmann, S., and Andreae, M O.: Size matters more than chemistry for cloud-nucleating ability of aerosol particles, Science, 312, 1375–1378, 2006. Edgerton, E S., Saylor, R D., Hartsell, B E., Jansen, J J., and Hansen, D A.: Ammonia and ammonium measurements from the southeastern United States, Atmos. Environ., 41, 3339–3351, 2007. Facchini, M C., Mircea, M., Fuzzi, S., and Charlson, R J.: Cloud albedo enhancement by surface-active organic solutes in growing droplets, Nature, 401, 257–259, 1999. Feingold, G. and Chuang, P Y.: Analysis of the influence of film-forming compounds on droplet growth: Implications for cloud microphysical processes and climate, J. Atmos. Sci., 59, 2006–2018, 2002. Fitzgerald, J W., Hoppel, W A., and Vietti, M A.: The size and scattering coefficient of urban aerosol-particles at Washington, DC as a function of relative-humidity, J. Atmos. Sci., 39, 1838–1852, 1982. Fitzgerald, J W. and Hoppel, W A.: Measurement of the relationship between the dry size and critical supersaturation of natural aerosol particles, J. Hung. Meteorol. Serv., 86, 242–248, 1982. Fridlind, A M. and Jacobson, M Z.: A study of gas-aerosol equilibrium and aerosol pH in the remote marine boundary layer during the First Aerosol Characterization Experiment (ACE 1), J. Geophys. Res., 105, 17 325–17 340, 2000. Fridlind, A M., Jacobson, M Z., Kerminen, V M., Hillamo, R E., Ricard, V., and Jaffrezo, J L.: Analysis of gas-aerosol partitioning in the Arctic: Comparison of size-resolved equilibrium model results with field data, J. Geophys. Res., 105, 19 891–19 903, 2000. Fuller, K A., Malm, W C., and Kreidenweis, S M.: Effects of mixing on extinction by carbonaceous particles, J. Geophys. Res., 104, 15 941–15 954, 1999. Gerber, H E., Hoppel, W A., and Wojciechowski, T A.: Experimental verification of the theoretical relationship between size and critical supersaturation of salt nuclei, J. Atmos. Sci., 34, 1836–1841, 1977. Glagolenko, S. and Phares, D J.: Single-particle analysis of ultrafine aerosol in College Station, Texas, J. Geophys. Res., 109, D18205, doi:10.1029/2004JD004621, 2004. Gorzelska, K., Talbot, R W., Klemm, K., Lefer, B., Klemm, O., Gregory, G L., Anderson, B., and Barrie, L A.: Chemical-composition of the atmospheric aerosol in the troposphere over the Hudson-Bay Lowlands and Quebec-Labrador Regions of Canada, J. Geophys. Res., 99, 1763–1779, 1994. Gysel, M., Crosier, J., Topping, D O., Whitehead, J D., Bower, K N., Cubison, M J., Williams, P I., Flynn, M J., McFiggans, G B., and Coe, H.: Closure study between chemical composition and hygroscopic growth of aerosol particles during TORCH2, Atmos. Chem. Phys., 7, 6131–6144, 2007. Hegg, D A., Covert, D S., Jonsson, H., and Covert, P A.: Determination of the transmission efficiency of an aircraft aerosol inlet, Aerosol Sci. Tech., 39, 966–971, 2005. Hildemann, L M., Russell, A G., and Cass, G R.: Ammonia and nitric-acid concentrations in equilibrium with atmospheric aerosols – experiment vs theory, Atmos. Environ., 18, 1737–1750, 1984. Hudson, J G. and Da, X Y.: Volatility and size of cloud condensation nuclei, J. Geophys. Res., 101, 4435–4442, 1996. Hutchinson, G L., Mosier, A R., and Andre, C E.: Ammonia and amine emissions from a large cattle feedlot, J. Environ. Qual., 11, 288–293, 1982. Khlystov, A., Stanier, C O., Takahama, S., and Pandis, S N.: Water content of ambient aerosol during the Pittsburgh air quality study, J. Geophys. Res., 110, D07S10, doi:10.1029/2004JD004651, 2005. Kleeman, M J., Hughes, L S., Allen, J O., and Cass, G R.: Source contributions to the size and composition distribution of atmospheric particles: Southern California in September 1996, Environ. Sci. Technol., 33, 4331–4341, 1999. Kreidenweis, S M., Koehler, K., DeMott, P J., Prenni, A J., Carrico, C., and Ervens, B.: Water activity and activation diameters from hygroscopicity data – Part I: Theory and application to inorganic salts, Atmos. Chem. Phys., 5, 1357–1370, 2005. Kumar, P P., Broekhuizen, K., and Abbatt, J P D.: Organic acids as cloud condensation nuclei: Laboratory studies of highly soluble and insoluble species, Atmos. Chem. Phys., 3, 509–520, 2003. Lance, S., Medina, J., Smith, J N., and Nenes, A.: Mapping the operation of the DMT Continuous Flow CCN counter, Aerosol Sci. Tech., 40, 242–254, 2006. Lobert, J M., Scharffe, D H., Hao, W M., Kuhlbusch, T A., Warneck, P., and Crutzen, P J.: Experimental evaluation of biomass burning emissions: Nitrogen and carbon containing compounds, in: Global Biomass Burning: Atmospheric, Climate and Biospheric Implications, edited by: Levine, J. S., MIT Press, Cambridge, MA, 1991. Makela, J M., Yli-Koivisto, S., Hiltunen, V., Seidl, W., Swietlicki, E., Teinila, K., Sillanpaa, M., Koponen, I K., Paatero, J., Rosman, K., and Hameri, K.: Chemical composition of aerosol during particle formation events in boreal forest, Tellus B, 53, 380–393, 2001. Manahan, S E.: Environmental Chemistry, Eighth Edition, CRC Press, Boca Raton, Florida, 2005. Maria, S F., Russell, L M., Turpin, B J., Porcja, R J., Campos, T L., Weber, R J., and Huebert, B J.: Source signatures of carbon monoxide and organic functional groups in Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) submicron aerosol types, J. Geophys. Res., 108, 8637, doi:10.1029/2003JD003703, 2003. McLafferty, F W. and Turecek, F.: Interpretation of Mass Spectra, Fourth Edition, University Science Books, Mill Valley, California, 1993. Meng, Z Y. and Seinfeld, J H.: Time scales to achieve atmospheric gas-aerosol equilibrium for volatile species, Atmos Environ., 30, 2889–2900, 1996. Milne, P J. and Zika, R G.: Amino-acid nitrogen in atmospheric aerosols – occurrence, sources and photochemical modification, J. Atmos. Chem., 16, 361–398, 1993. Mochida, M., Kuwata, M., Miyakawa, T., Takegawa, N., Kawamura, K., and Kondo, Y.: Relationship between hygroscopicity and cloud condensation nuclei activity for urban aerosols in Tokyo, J. Geophys. Res., 111, D23204, doi:10.1029/2005JD006980, 2006. Moore, R H., Ingall, E D., Sorooshian, A., and Nenes, A.: Molar mass, surface tension, and droplet growth kinetics of marine organics from measurements of CCN activity, Geophys. Res. Lett., 35, L07801, doi:10.1029/2008GL033350, 2008. Mosier, A R., Andre, C E., and Viets, F G.: Identification of Aliphatic-Amines Volatilized from Cattle Feedyard, Environ. Sci. Technol., 7, 642–644, 1973. Mozurkewich, M.: The dissociation-constant of ammonium-nitrate and Its dependence on temperature, relative-humidity and particle-size, Atmos Environ., 27, 261–270, 1993. Murphy, D M. and Thomson, D S.: Chemical composition of single aerosol particles at Idaho Hill: Positive ion measurements, J. Geophys. Res., 102, 6341–6352, 1997. Murphy, S M., Sorooshian, A., Kroll, J H., Ng, N L., Chhabra, P., Tong, C., Surratt, J D., Knipping, E., Flagan, R C., and Seinfeld, J. H.: Secondary aerosol formation from atmospheric reactions of aliphatic amines, Atmos. Chem. Phys., 7, 2313–2337, 2007. Nenes, A., Charlson, R J., Facchini, M C., Kulmala, M., Laaksonen, A., and Seinfeld, J H.: Can chemical effects on cloud droplet number rival the first indirect effect?, Geophys. Res. Lett., 29, 1848, doi:10.1029/2002GL015295, 2002. Neuman, J A., Nowak, J B., Brock, C A., Trainer, M., Fehsenfeld, F C., Holloway, J S., Hubler, G., Hudson, P K., Murphy, D M., Nicks, D K., Orsini, D., Parrish, D D., Ryerson, T B., Sueper, D T., Sullivan, A., and Weber, R.: Variability in ammonium nitrate formation and nitric acid depletion with altitude and location over California, J. Geophys. Res., 108, 4557, doi:10.1029/2003JD003616, 2003. Ngwabie, N M., Custer, T G., Schade, G W., Linke, S., and Hinz, T.: Mixing ratio measurements and flux estimates of volatile organic compounds (VOC) from a cowshed with conventional manure treatment indicate significant emissions to the atmosphere, Geophys. Res. Abstr., 7(01175), 2005. Petters, M D. and Kreidenweis, S M.: A single parameter representation of hygroscopic growth and cloud condensation nucleus activity. Atmos. Chem. Phys., 7, 1961–1971, 2007. Prenni, A J., De Mott, P J., and Kreidenweis, S M.: Water uptake of internally mixed particles containing ammonium sulfate and dicarboxylic acids, Atmos Environ., 37, 4243–4251, 2003. Pun, B K. and Seigneur, C.: Understanding particulate matter formation in the California San Joaquin Valley: conceptual model and data needs, Atmos. Environ., 33, 4865–4875, 1999. Rabaud, N E., Ebeler, S E., Ashbaugh, L L., and Flocchini, R G.: Characterization and quantification of odorous and non-odorous volatile organic compounds near a commercial dairy in California, Atmos. Environ., 37, 933–940, 2003. Rissler, J., Pagels, J., Swietlicki, E., Wierzbicka, A., Strand, M., Lillieblad, L., Sanati, M., and Bohgard, M.: Hygroscopic behavior of aerosol particles emitted from biomass fired grate boilers, Aerosol Sci. Tech., 39, 919–930, 2005. Rissler, J., Vestin, A., Swietlicki, E., Fisch, G., Zhou, J., Artaxo, P., and Andreae, M O.: Size distribution and hygroscopic properties of aerosol particles from dry-season biomass burning in Amazonia, Atmos. Chem. Phys., 6, 471–491, 2006. Roberts, G C. and Nenes, A.: A continuous-flow streamwise thermal-gradient CCN chamber for atmospheric measurements, Aerosol Sci. Tech., 39, 206–221, 2005. Rose, D., Gunthe, S S., Mikhailov, E., Frank, G P., Dusek, U., Andreae, M O., and Poschl, U.: Calibration and measurement uncertainties of a continuous-flow cloud condensation nuclei counter (DMT-CCNC): CCN activation of ammonium sulfate and sodium chloride aerosol particles in theory and experiment, Atmos. Chem. Phys., 8, 1153–1179, 2008. Ruehl, C R., Chuang, P Y., and Nenes, A.: How quickly do cloud droplets form on atmospheric particles?, Atmos. Chem. Phys., 8, 1043–1055, 2008. Rumburg, B., Mount, G H., Yonge, D., Lamb, B., Westberg, H., Filipy, J., Bays, J., Kincaid, R., and Johnson, K.: Atmospheric flux of ammonia from sprinkler application of dairy waste, Atmos Environ., 40, 7246–7258, 2006. Russell, A G., Mcrae, G J., and Cass, G R.: Mathematical-modeling of the formation and transport of ammonium-nitrate aerosol, Atmos. Environ., 17, 949–964, 1983. Schade, G W. and Crutzen, P J.: Emission of aliphatic-amines from animal husbandry and their reactions - potential source of N2O and HCN, J. Atmos. Chem., 22, 319–346, 1995. Seinfeld, J H. and Pandis, S N.: Atmospheric Chemistry and Physics, Second Edition, Wiley-Interscience, New York, 2006. Shulman, M L., Jacobson, M C., Carlson, R J., Synovec, R E., and Young, T E.: Dissolution behavior and surface tension effects of organic compounds in nucleating cloud droplets, Geophys. Res. Lett., 23, 277–280, 1996. Sjogren, S., Gysel, M., Weingartner, E., Baltensperger, U., Cubison, M J., Coe, H., Zardini, A A., Marcolli, C., Krieger, U K., and Peter, T.: Hygroscopic growth and water uptake kinetics of two-phase aerosol particles consisting of ammonium sulfate, adipic and humic acid mixtures, J. Aerosol Sci., 38, 157–171, 2007. Sorooshian, A., Brechtel, F J., Ma, Y L., Weber, R J., Corless, A., Flagan, R C., and Seinfeld, J H.: Modeling and characterization of a particle-into-liquid sampler (PILS), Aerosol Sci. Tech., 40, 396–409, 2006a. Sorooshian, A., Varutbangkul, V., Brechtel, F J., Ervens, B., Feingold, G., Bahreini, R., Murphy, S M., Holloway, J S., Atlas, E L., Buzorius, G., Jonsson, H., Flagan, R C., and Seinfeld, J H.: Oxalic acid in clear and cloudy atmospheres: Analysis of data from International Consortium for Atmospheric Research on Transport and Transformation 2004, J. Geophys. Res., 111, D23S45, doi:10.1029/2005JD006880, 2006b. Sorooshian, A., Ng, N L., Chan, A W H., Feingold, G., Flagan, R C., and Seinfeld, J H.: Particulate organic acids and overall water-soluble aerosol composition measurements from the 2006 Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS), J. Geophys. Res., 112, D13201, doi:10.1029/2007JD008537, 2007a. Sorooshian, A., Lu, M L., Brechtel, F J., Jonsson, H., Feingold, G., Flagan, R C., and Seinfeld, J H.: On the source of organic acid aerosol layers above clouds, Environ. Sci. Technol., 41, 4647–4654, 2007b. Sorooshian, A., S. Hersey, F J. Brechtel, A. Corless, R C. Flagan, and Seinfeld, J H.: Rapid, size-resolved aerosol hygroscopic growth measurements: differential aerosol sizing and hygroscopicity spectrometer probe (DASH-SP), Aerosol Sci. Tech., 42, 445–464, 2008. Stelson, A W., Friedlander, S K., and Seinfeld, J H.: Note on the equilibrium relationship between ammonia and nitric-acid and particulate ammonium-nitrate, Atmos. Environ., 13, 369–371, 1979. Stelson, A W. and Seinfeld, J H.: Relative-humidity and temperature-dependence of the ammonium-nitrate dissociation-constant, Atmos. Environ., 16, 983–992, 1982a. Stelson, A W. and Seinfeld, J H.: Relative-humidity and Ph-dependence of the vapor-pressure of ammonium-nitrate nitric acid-solutions at 25 degrees C, Atmos. Environ., 16, 993–1000, 1982b. Stokes, R H. and Robinson, R A.: Interactions in aqueous nonelectrolyte solutions .I. Solute-solvent equilibria, J. Phys. Chem., 70, 2126–2130, 1966. Svenningsson, I B., Hansson, H C., Wiedensohler, A., Ogren, J A., Noone, K J., and Hallberg, A.: Hygroscopic growth of aerosol-particles in the Po Valley, Tellus B, 44, 556–569, 1992. Svenningsson, B., Rissler, J., Swietlicki, E., Mircea, M., Bilde, M., Facchini, M C., Decesari, S., Fuzzi, S., Zhou, J., Monster, J., and Rosenorn, T.: Hygroscopic growth and critical supersaturations for mixed aerosol particles of inorganic and organic compounds of atmospheric relevance, Atmos. Chem. Phys., 6, 1937–1952, 2006. Takahama, S., Wittig, A E., Vayenas, D V., Davidson, C I., and Pandis, S N.: Modeling the diurnal variation of nitrate during the Pittsburgh Air Quality Study, J. Geophys. Res., 109, D16S06, doi:10.1029/2003JD004149, 2004. Tan, P V., Evans, G J., Tsai, J., Owega, S., Fila, M S., and Malpica, O.: On-line analysis of urban particulate matter focusing on elevated wintertime aerosol concentrations, Environ. Sci. Technol., 36, 3512–3518, 2002. Tang, I N.: Chemical and size effects of hygroscopic aerosols on light scattering coefficients, J. Geophys. Res., 101, 19 245–19 250, 1996. Taraniuk, I., Graber, E R., Kostinski, A., and Rudich, Y.: Surfactant properties of atmospheric and model humic-like substances (HULIS), Geophys. Res. Lett., 34, L16807, doi:10.1029/2007GL029576, 2007. Ulbrich, I M., Lechner, M., and Jimenez, J L.: AMS Spectral Database, http://cires.colorado.edu/jimenez-group/AMSsd/, 2008. Ulbrich, I M., Canagaratna, M R., Zhang, Q., Worsnop, D R., and Jimenez, J L.: Interpretation of organic components from positive matrix factorization of aerosol mass spectrometric data, Atmos. Chem. Phys. Discuss., 8, 6729–6791, 2008. Vanneste, A., Duce, R A., and Lee, C.: Methylamines in the marine atmosphere, Geophys. Res. Lett., 14, 711–714, 1987. Varutbangkul, V., Brechtel, F J., Bahreini, R., Ng, N L., Keywood, M D., Kroll, J H., Flagan, R C., Seinfeld, J H., Lee, A., and Goldstein, A H.: Hygroscopicity of secondary organic aerosols formed by oxidation of cycloalkenes, monoterpenes, sesquiterpenes, and related compounds, Atmos. Chem. Phys., 6, 2367–2388, 2006. Weast, R C.: CRC Handbook of Chemistry and Physics, Sixty Eighth Edition, CRC Press, Florida, 1987. Westerholm, R., Li, H., and Almen, J.: Estimation of aliphatic amine emissions in automobile exhausts, Chemosphere, 27, 1381–1384, 1993. Wexler, A S. and Seinfeld, J H.: Analysis of aerosol ammonium-nitrate - departures from equilibrium during Scaqs, Atmos. Environ., 26, 579–591, 1992. Wise, M E., Surratt, J D., Curtis, D B., Shilling, J E., and Tolbert, M A.: Hygroscopic growth of ammonium sulfate/dicarboxylic acids, J. Geophys. Res., 108, 4638, doi:10.1029/2003JD003775, 2003. Xiong, J Q., Zhong, M H., Fang, C P., Chen, L C., and Lippmann, M.: Influence of organic films on the hygroscopicity of ultrafine sulfuric acid aerosol, Environ. Sci. Technol., 32, 3536–3541, 1998. Yu, S C., Dennis, R., Roselle, S., Nenes, A., Walker, J., Eder, B., Schere, K., Swall, J., and Robarge, W.: An assessment of the ability of three-dimensional air quality models with current thermodynamic equilibrium models to predict aerosol NO3-, J. Geophys. Res., 110, D07S13, doi:10.1029/2004JD004718, 2005. Zdanovskii, A.: New methods for calculating solubilities of electrolytes in multicomponent systems, Zh. Fiz. Khim.+, 22, 1475–1485, 1948. Zhang, J., Chameides, W L., Weber, R., Cass, G., Orsini, D., Edgerton, E., Jongejan, P., and Slanina, J.: An evaluation of the thermodynamic equilibrium assumption for fine particulate composition: Nitrate and ammonium during the 1999 Atlanta Supersite Experiment, J. Geophys. Res., 108, 8414, doi:10.1029/2001JD001592, 2002. Zhang, X Q., Turpin, B J., McMurry, P H., Hering, S V., and Stolzenburg, M R.: Mie theory evaluation of species contributions to 1990 wintertime visibility reduction in the Grand-Canyon, J. Air Waste Manage., 44, 153–162, 1994. Zhang, Q., Anastasio, C., and Jimenez-Cruz, M.: Water-soluble organic nitrogen in atmospheric fine particles (PM2.5) from northern California, J. Geophys. Res., 107, 4112, doi:10.1029/2001JD000870, 2002. Zhang, Q. and Anastasio, C.: Free and combined amino compounds in atmospheric fine particles (PM2.5) and fog waters from Northern California, Atmos. Environ., 37, 2247–2258, 2003. Zhang, Q., Alfarra, M R., Worsnop, D R., Allan, J D., Coe, H., Canagaratna, M R., and Jimenez, J L.: Deconvolution and quantification of hydrocarbon-like and oxygenated organic aerosols based on aerosol mass spectrometry, Environ. Sci. Technol., 39, 4938–4952, 2005.