1. Organic Functional Group Composition and Sources of Ambient Aerosol during CalNex 2010 Amanda Frossard, Lynn Russell, Scripps Institution of Oceanography, UC San Diego Timothy Bates, and Patricia Quinn Pacific Marine Environmental Laboratory, NOAA Photo Credit: P.M. Shaw

2. Overview Organic Aerosol Collection and Quantification Organic Mass Composition Technique Comparison PMF Source Contributions Single Particle Composition Potential Source Locations Photo Credit: P.M. Shaw

3. Organic Aerosol Sampling Mass Flow Meter and Controller Total: 16.8 lpm Vacuum Pump PM1 Cyclone 2 pairs of Teflon filters Dried to 55% RH

4. Organic Aerosol Sampling Four Sampling Regions: Southern California Coastal Transit San Francisco Sacramento

5. Organic Mass Composition Southern California Coastal Transit San Francisco Sacramento

6. Overall Organic Mass Composition Ratio of O/C: 0.46 μg m -3 Total OM: 1.64 μg m -3 – Alcohol: 0.26 μg m -3 (16%) – Acid: 0.51 μg m -3 (31%) – Alkane: 0.83 μg m -3 (51%) – Amine: 0.05 μg m -3 (3%) Southern California Coastal Transit San Francisco Sacramento 2.11 μg m -3 0.51 μg m -3 0.58 μg m -3 0.78 μg m -3

7. Technique Comparison Q-AMS OM = 0.83*FTIR OM r = 0.82 Lower OM in the Q-AMS could be due to organics on dust, submicron sea salt, or other refractory particles

8. Source Contributions More oxygenated “aged” 76% of OM Less oxygenated “fresh” 12% of OM

9. Source Contributions Southern California Coastal Transit San Francisco Sacramento

10. Combustion Factors Less oxygenated More oxygenated Russell et al. 2011, in press

11. Oxygenated Combustion Factor r = 0.82 Expect that most sulfate is secondary, so correlation with OM suggests the OM is also SOA

12. Single Particles: Sacramento Combustion Secondary

13. Single Particles: LA Harbor Combustion Secondary

14. Source Contributions Organic Mass Carboxylic Acid Concentration

15. Source Contributions Aged Combustion Fresh Combustion

16. Summary Average organic mass: 1.64 μg m -3 Two combustion sources – More oxygenated (76% of OM) – Less oxygenated Single Particle analysis – Secondary and combustion particles OM from continental sources

17. Thanks! Acknowledgements: Scientists and crew of R/V Atlantis The LBNL Beamline group Russell group Dan Czizco and PNNL PMEL and Uva Atlantis Groups