1. Aerosol Chemical Composition Using Aerosol Mass Spectrometry ASCOS Workshop Landskrona April 9, 2008 R. Chang, J. Abbatt – University of Toronto K. Hayden, R. Leaitch, S.-M. Li, J. Liggio – Environment Canada

2. Objectives characterize composition of surface aerosols –physical properties, hygroscopic properties source of air –local natural aerosol Does it correlate with biological activity? Is there an organic component? Are the aerosols neutralized? Is there enough ammonia present? Is there MSA in the aerosol? –transported anthropogenic aerosol Are the aerosols neutralized? Is there an organic component?

3. Time-of-Flight Aerosol Mass Spectrometer Mass Spectrum Mode

4. SOLAS 2007 in Canadian Arctic Clean 2 Clean 1 Organic Nitrate Sulphate Ammonium Chloride

5. Clean 1 Number Volume

6. Sulphate MS Neutralized Clean 1 NIST H 2 SO 4

7. Time-of-Flight Aerosol Mass Spectrometer Particle Time of Flight Mode (PToF)

8. PToF Distribution in Southern Ontario Sulphate Organic Ammonium Nitrate Chloride

9. J. Bottenheim, S. Netcheva – Environment Canada ASCOS Workshop Landskrona April 9, 2008 Halogen Chemistry with Out On The Ice (OOTI)

10. Introduction Spring time chemistry Br 2 + hν → 2Br 2(Br + O 3 → BrO + O 2 )(O 3 depletion) BrO + DMS  DMSO Br/BrO + Hg 0  RGM  mercury deposition Question: Can this chemistry occur in the summer?

11. Instrumentation for Target Species BrO: Multi-Axis Differential Optical Absorption Spectrometer (MaxDOAS, Ocean Optics) O 3 : UV Absorption Based Monitor (2B) Hg 0 : Atomic Absorption Mercury Vapour Analyzer (Gardis)