New particle formation at a remote continental site: Assessing the contributions of SO2 and organic precursors

Ultrafine aerosols, with diameters less than 10 nm, nucleate from gas phase species. The composition of newly formed ultrafine atmospheric aerosols is not known with certainty; new particles have variously been conjectured to be sulfates, organic compounds, and sulfate/organic mixtures. The 1993 Tropospheric OH Photochemistry Experiment at Idaho Hill, Colorado, provided an opportunity to examine the question of which class of compounds, i.e., sulfates or organics, make the major contribution to new particle formation in the unpolluted troposphere. This study compared the production rates of sulfuric acid (from the oxidation of sulfur dioxide) and oxidized organic compounds to gauge their relative contributions to the formation of ultrafine particles. Potential organic precursor species examined in this study were the naturally occurring terpenes α– and β pinene, and the anthropogenic hydrocarbons toluene, m-xylene, ethyl benzene, 1,2,4 trimethyl benzene, and methylcyclohexane. The calculated production of oxidized organics appeared well correlated with total particle surface area and volume, suggesting that at least some of the organic compounds formed in gas phase reactions condensed upon the preexisting aerosol. New particle formation was found to be more highly associated with elevated production of gas phase sulfuric acid (via the SO2-OH reaction) than with production of oxidized organic products, although data from one day, during which sulfuric acid production and total aerosol surface area were both lower than usual, provided evidence for the involvement of terpene species in new particle formation. The results suggest that for this continental site, sulfuric acid was probably responsible for most of the observed new ultrafine particle formation. Low-volatility organic compounds may have caused particle formation under the right conditions, but were more likely to condense upon preexisting particles.

[1]  J. Tyndall.  IX. On a new series of chemical reactions produced by light , 2011, Proceedings of the Royal Society of London.

[2]  A. J. Haagen-Smit,et al.  Ozone formation in photochemical oxidation of organic substances , 1953 .

[3]  F. Went.  Blue Hazes in the Atmosphere , 1960, Nature.

[4]  G. J. Doyle.  Self‐Nucleation in the Sulfuric Acid‐Water System , 1961 .

[5]  O. J. Kleppa,et al.  Volume Change on Mixing in Liquid Sodium‐Potassium Nitrates , 1961 .

[6]  R. Rasmussen,et al.  VOLATILE ORGANIC MATERIAL OF PLANT ORIGIN IN THE ATMOSPHERE. , 1965, Proceedings of the National Academy of Sciences of the United States of America.

[7]  F. Went.  On the nature of Aitken condensation nuclei , 1966 .

[8]  A. Hogan.  An experiment illustrating that gas conversion by solar radiation is a major influence in the diurnal variation of Aitken nucleus concentrations , 1968 .

[9]  R. Charlson,et al.  H2SO4/(NH4)2SO4 background aerosol: optical detection in St. Louis region. , 1974, Atmospheric environment.

[10]  J. Katz,et al.  Binary homogeneous nucleation as a mechanism for the formation of aerosols , 1974 .

[11]  Robert A. Duce,et al.  The organic carbon content of marine aerosols collected on Bermuda , 1974 .

[12]  R. Charlson,et al.  Sulfate Aerosol: Its Geographical Extent in the Midwestern and Southern United States , 1977, Science.

[13]  G. Ketseridis,et al.  Organic compounds in aerosol samples , 1978 .

[14]  T. Graedel.  Terpenoids in the atmosphere , 1979 .

[15]  S. Friedlander,et al.  New particle formation in the presence of an aerosol , 1979 .

[16]  Peter H. McMurry,et al.  Photochemical aerosol formation from SO2: A theoretical analysis of smog chamber data , 1980 .

[17]  Donald E. Hagen,et al.  Linear inversion method to obtain aerosol size distributions from measurements with a differential mobility analyzer , 1983 .

[18]  P. Mcmurry.  New particle formation in the presence of an aerosol: Rates, time scales, and sub-0.01 μm size distributions , 1983 .

[19]  T. L. Wolfe,et al.  An assessment of the impact of pollution on global cloud albedo , 1984 .

[20]  Y. Yokouchi,et al.  AEROSOLS FORMED FROM THE CHEMICAL REACTION OF MONOTERPENES AND OZONE , 1985 .

[21]  H. Cachier,et al.  Long‐range transport of continentally‐derived particulate carbon in the marine atmosphere: evidence from stable carbon isotope studies , 1986 .

[22]  J. Seinfeld.  Atmospheric Chemistry and Physics of Air Pollution , 1986 .

[23]  J. Seinfeld,et al.  Aerosol formation and growth in atmospheric aromatic hydrocarbon photooxidation , 1987 .

[24]  H. Akimoto,et al.  Reactions of ozone with α‐pinene and β‐pinene in air: Yields of gaseous and particulate products , 1989 .

[25]  A. Jaecker-Voirol,et al.  Heteromolecular nucleation in the sulfuric acid-water system , 1989 .

[26]  John H. Seinfeld,et al.  Parameterization of the formation potential of secondary organic aerosols , 1989 .

[27]  Benjamin Y. H. Liu,et al.  Particle activation and droplet growth processes in condensation nucleus counter—I. Theoretical background☆ , 1990 .

[28]  S. M. Aschmann,et al.  Product study of the gas-phase reactions of monoterpenes with the OH radical in the presence of NO x , 1990 .

[29]  James J. Marti.  Diurnal variation in the undisturbed continental aerosol : results from a measurement program in Arizona , 1990 .

[30]  R. Flagan,et al.  Scanning Electrical Mobility Spectrometer , 1990 .

[31]  H. Akimoto,et al.  Reactions of OH with α‐pinene and β‐pinene in air: Estimate of global CO production from the atmospheric oxidation of terpenes , 1991 .

[32]  J. Seinfeld,et al.  Aerosol formation during photooxidation of organosulfur species , 1991 .

[33]  John H. Seinfeld,et al.  Aerosol formation in the photooxidation of isoprene and β-pinene , 1991 .

[34]  Peter H. McMurry,et al.  An Ultrafine Aerosol Condensation Nucleus Counter , 1991 .

[35]  R. Dingenen,et al.  Simulations of condensation and cloud condensation nuclei from biogenic SO2 in the remote marine boundary layer , 1992 .

[36]  John H. Seinfeld,et al.  Atmospheric oxidation of selected terpenes and related carbonyls: gas-phase carbonyl products , 1992 .

[37]  J. Seinfeld,et al.  Aerosol formation and growth in atmospheric organic/NOχ systems—I. Outdoor smog chamber studies of C7- and C8-hydrocarbons , 1992 .

[38]  J. Coakley,et al.  Climate Forcing by Anthropogenic Aerosols , 1992, Science.

[39]  J. Seinfeld,et al.  Fourier transform infrared analysis of aerosol formed in the photo-oxidation of isoprene and β-pinene , 1992 .

[40]  S. Hering,et al.  Mixing characteristics and water content of submicron aerosols measured in Los Angeles and at the grand canyon , 1993 .

[41]  D. Tanner,et al.  Measurement of the gas phase concentration of H2SO4 and methane sulfonic acid and estimates of H2SO4 production and loss in the atmosphere , 1993 .

[42]  J. Penner,et al.  Large contribution of organic aerosols to cloud-condensation-nuclei concentrations , 1993, Nature.

[43]  W. Malm,et al.  Spatial and seasonal trends in particle concentration and optical extinction in the United States , 1994 .

[44]  Leonard K. Peters,et al.  Binary Homogeneous Nucleation: Temperature and Relative Humidity Fluctuations, Nonlinearity, and Aspects of New Particle Production in the Atmosphere , 1994 .

[45]  P. Mcmurry,et al.  Measurement of Expected Nucleation Precursor Species and 3–500-nm Diameter Particles at Mauna Loa Observatory, Hawaii , 1995 .

[46]  R. Atkinson,et al.  Atmospheric lifetimes and fates of a series of sesquiterpenes , 1995 .

[47]  F. Raes.  Entrainment of free tropospheric aerosols as a regulating mechanism for cloud condensation nuclei in the remote marine boundary layer , 1995 .

[48]  P. Mcmurry,et al.  Ultrafine Aerosol Measurement Using a Condensation Nucleus Counter with Pulse Height Analysis , 1996 .

[49]  C. F. Rogers,et al.  Derivation of contributions of sulfate and carbonaceous aerosols to cloud condensation nuclei from mass size distributions , 1996 .

[50]  R. Jakoubek,et al.  Measurement of tropospheric OH by long-path laser absorption at Fritz Peak Observatory, Colorado, during the OH Photochemistry Experiment, fall 1993 , 1997 .

[51]  P. Mcmurry,et al.  Measurements of new particle formation and ultrafine particle growth rates at a clean continental site , 1997 .

[52]  F. Fehsenfeld,et al.  Ground‐based comparison of NO2, H2O, and O3 measured by long‐path and in situ techniques during the 1993 Tropospheric OH Photochemistry Experiment , 1997 .

[53]  F. Fehsenfeld,et al.  Nonmethane hydrocarbon measurements during the Tropospheric OH Photochemistry Experiment , 1997 .

[54]  G. Mount,et al.  An overview of the Tropospheric OH Photochemistry Experiment, Fritz Peak/Idaho Hill, Colorado, fall 1993 , 1997 .

[55]  J. Harder,et al.  Meteorological overview of the 1993 OH Photochemistry Experiment , 1997 .