Cloud condensation nuclei activity of fresh primary and aged biomass burning aerosol

Abstract. We quantify the hygroscopic properties of particles freshly emitted from biomass burning and after several hours of photochemical aging in a smog chamber. Values of the hygroscopicity parameter, κ, were calculated from cloud condensation nuclei (CCN) measurements of emissions from combustion of 12 biomass fuels commonly burned in North American wildfires. Prior to photochemical aging, the κ of the fresh primary aerosol varied widely, between 0.06 (weakly hygroscopic) and 0.6 (highly hygroscopic). The hygroscopicity of the primary aerosol was positively correlated with the inorganic mass fraction of the particles. Photochemical processing reduced the range of κ values to between 0.08 and 0.3. The changes in κ were driven by the photochemical production of secondary organic aerosol (SOA). SOA also contributed to growth of particles formed during nucleation events. Analysis of the nucleation mode particles enabled the first direct quantification of the hygroscopicity parameter κ for biomass burning SOA, which was on average 0.11, similar to values observed for biogenic SOA. Although initial CCN activity of biomass burning aerosol emissions are highly variable, after a few hours of photochemical processing κ converges to a value of 0.2 ± 0.1. Therefore, photochemical aging reduces the variability of biomass burning CCN κ, which should simplify analysis of the potential effects of biomass burning aerosol on climate.

[1]  T. Petäjä,et al.  Relationship between aerosol oxidation level and hygroscopic properties of laboratory generated secondary organic aerosol (SOA) particles , 2010 .

[2]  S. Twomey,et al.  The Production of Cloud Nuclei by Cane Fires and the Effect on Cloud Droplet Concentration , 1967 .

[3]  Qi Zhang,et al.  O/C and OM/OC ratios of primary, secondary, and ambient organic aerosols with high-resolution time-of-flight aerosol mass spectrometry. , 2008, Environmental science & technology.

[4]  Remo Guidieri.  Res , 1995, RES: Anthropology and Aesthetics.

[5]  L. Radke,et al.  Cloud Condensation Nuclei from a Simulated Forest Fire , 1969, Science.

[6]  Rajan K. Chakrabarty,et al.  Emissions from the laboratory combustion of wildland fuels: Particle morphology and size , 2006 .

[7]  A. Robinson,et al.  New particle formation and growth in biomass burning plumes: An important source of cloud condensation nuclei , 2012 .

[8]  T. Eck,et al.  A review of biomass burning emissions part III: intensive optical properties of biomass burning particles , 2004 .

[9]  Ulrich Pöschl,et al.  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 , 2007 .

[10]  H. Wernli,et al.  Aerosol- and updraft-limited regimes of cloud droplet formation: influence of particle number, size and hygroscopicity on the activation of cloud condensation nuclei (CCN) , 2009 .

[11]  A. Weinheimer,et al.  Investigation of the sources and processing of organic aerosol over the Central Mexican Plateau from aircraft measurements during MILAGRO , 2010 .

[12]  Y. H. Zhang,et al.  Cloud condensation nuclei in polluted air and biomass burning smoke near the mega-city Guangzhou, China – Part 1: Size-resolved measurements and implications for the modeling of aerosol particle hygroscopicity and CCN activity , 2008 .

[13]  E. Atlas,et al.  Emissions from biomass burning in the Yucatan , 2009 .

[14]  Allen L. Robinson,et al.  Levoglucosan stability in biomass burning particles exposed to hydroxyl radicals , 2010 .

[15]  A. Nenes,et al.  A Continuous-Flow Streamwise Thermal-Gradient CCN Chamber for Atmospheric Measurements , 2005 .

[16]  A. Nenes,et al.  Cloud condensation nuclei activity of isoprene secondary organic aerosol , 2011 .

[17]  J. Levine.  Cloud Condensation Nuclei from Biomass Burning , 1991 .

[18]  M. Petters,et al.  A single parameter representation of hygroscopic growth and cloud condensation nucleus activity , 2006 .

[19]  Thomas W. Kirchstetter,et al.  Emissions of trace gases and aerosols during the open combustion of biomass in the laboratory , 2009 .

[20]  P. Adams,et al.  Contribution of primary carbonaceous aerosol to cloud condensation nuclei: processes and uncertainties evaluated with a global aerosol microphysics model , 2007 .

[21]  M. Petters,et al.  Cloud condensation nucleation activity of biomass burning aerosol , 2009 .

[22]  P. Crutzen,et al.  Biomass Burning in the Tropics: Impact on Atmospheric Chemistry and Biogeochemical Cycles , 1990, Science.

[23]  Spyros N. Pandis,et al.  CCN activity and droplet growth kinetics of fresh and aged monoterpene secondary organic aerosol , 2008 .

[24]  Andrew A. May,et al.  Chemical and physical transformations of organic aerosol from the photo-oxidation of open biomass burning emissions in an environmental chamber , 2011 .

[25]  C. Corrigan,et al.  Cloud condensation nucleus activity of the organic component of biomass smoke particles , 1996 .

[26]  A. Nenes,et al.  Scanning Mobility CCN Analysis—A Method for Fast Measurements of Size-Resolved CCN Distributions and Activation Kinetics , 2010 .

[27]  W. R. Leaitch,et al.  The hygroscopicity parameter (κ) of ambient organic aerosol at a field site subject to biogenic and anthropogenic influences: relationship to degree of aerosol oxidation , 2010 .

[28]  M. Petters,et al.  On Measuring the Critical Diameter of Cloud Condensation Nuclei Using Mobility Selected Aerosol , 2007 .

[29]  M. Andreae,et al.  Smoking Rain Clouds over the Amazon , 2004, Science.

[30]  S. Martin,et al.  Cloud droplet activation of mixed organic-sulfate particles produced by the photooxidation of isoprene , 2010 .

[31]  Z. Jurányi,et al.  Relating cloud condensation nuclei activity and oxidation level ofα-pinene secondary organic aerosols: CCN AND OXIDATION LEVEL OFα-PINENE SOA , 2011 .

[32]  A. Nenes,et al.  Hygroscopicity and composition of Alaskan Arctic CCN during April 2008 , 2011 .

[33]  Allen L. Robinson,et al.  Fine particle and organic vapor emissions from staged tests of an in-use aircraft engine , 2011 .

[34]  Gerard Capes,et al.  Aging of biomass burning aerosols over West Africa: Aircraft measurements of chemical composition, microphysical properties, and emission ratios , 2008 .

[35]  Sonia M. Kreidenweis,et al.  Cloud droplet activation of secondary organic aerosol , 2007 .

[36]  Peter V. Hobbs,et al.  Measurements of Cloud Condensation Nuclei and Cloud Droplet Size Distributions in the Vicinity of Forest Fires , 1974 .

[37]  P. Forster,et al.  Global cloud condensation nuclei influenced by carbonaceous combustion aerosol , 2011 .

[38]  Sonia M. Kreidenweis,et al.  A single parameter representation of hygroscopic growth and cloud condensation nucleus activity – Part 3: Including surfactant partitioning , 2012 .