AEROSOL MASS SPECTROMETRY Application of the Aerodyne AMS in various field studies

1. Cloud Physics and Chemistry Department (CPCD) AEROSOL MASS SPECTROMETRY Application of the Aerodyne AMSin various field studies Johannes Schneider Department of Cloud Physics and ChemistryMax Planck Institute for Chemistry / University of Mainz, Germany

2. Outline • The Cloud Physics and Chemistry Department at Mainz • The Aerodyne Aerosol Mass Spectrometer (AMS) • Ground based aerosol measurements (MINOS, Crete, August 2001) • Aircraft based aerosol measurements(PAZI, May 2003) • Diesel exhaust measurements • Cloud residual particle measurements:Åreskutan/Sweden (Juli 2003) and Jungfraujoch/Switzerland (CLACE-3, March 2004) • Summary / Answers to leading questions

3. Cloud Physics and Chemistry Department (CPCD) Cloud Physics and Chemistry Department (CPCD) Head:Prof. Dr. Stephan Borrmann Research Groups: Johannes Schneider Subir Mitra Aerosol Mass Spectrometer (AMS)Field Campaigns Vertical Wind Tunnel(Rain Droplet and Ice Crystal Research) Frank Drewnick Joachim Curtius Time-of-flight Aerosol MassSpectrometry(Instrument Development) Ion Trap Aerosol Mass Spectrometry(Instrument Development) High Altitude Aircraft Particle Measurements Max Planck Institute University

4. The Aerodyne Aerosol Mass Spectrometer AMS Vaporizer ( 600 °C)

5. AMS - Modes of Operation • Time-of-flight mode • Mass size distribution for various m/z‘s as a function of “vacuum aerodynamic diameter“ (Dva). • Mass spec mode • Continuous scanning of mass range • Quantitative chemical composition (non-refractory) Transmission Ion Rate (Hz) dM/dlog(Dva) Vacuum aerodynamic diameter Vacuum aerodynamic diameter (nm) m/z

6. Mediterranean INtensive Oxidant StudyCrete, August 2001 MINOS Crete from: Lelieveld, J., et al., Global air pollution crossroads over the Mediterranean, Science, 298, 794-799, 2002.

7. MINOS - Time Series Schneider et al., Atmos. Chem. Phys., 4, 65-80, 2004. • Aerosol is dominated by sulfate. • Fossil fuel combustion in Middle and Eastern Europe influences Eastern Mediterranean.

8. MINOS - Size Distributions • MOUDI: Impactor with subsequent filter analysis • Comparison between MOUDI and AMS:good agreement for sulfate and ammonium, AMS has better detection limit than MOUDI • Better time resolution of AMS (Minutes  Hours) Schneider et al., Atmos. Chem. Phys., 4, 65-80, 2004.

9. Aircraft-based measurements First employment of an AMS on a jet aircraft (DLR-Falcon) (PAZI) Particles From Aircraft:Impact on Cirrus Clouds and Climate, May 2003, Oberpfaffenhofen, Germany

10. AMS aircraft configuration

11. Aircraft Inlet M. Fiebig, Ph.D. Thesis, 2001

12. Vertical Profiles • Pronounced boundary layer on flight #1 • Time resolution: 1 min sampling, averaged by altitude bins

13. Size distributions 3000 m 6000 m

14. Diesel exhaust particles Chassis dynamometer test facility of theFord Research Center Aachen

15. Nucleation particles I High FSC,w/o thermodenuder High FSC,with thermodenuder Low FSC,w/o thermodenuder

16. Individual car chasing • Individual car chasing on test track • AMS in Ford Mobile Lab • Distance 10 m, various speeds and FSCs

17. Nucleation Particles II J. Schneider et al.,Nucleation particles in Diesel exhaust: Composition inferred from in-situ mass spectrometric analysis,to be submitted to Env. Sci. Techn., May 2004.

18. Cloud residual particles SOACED (Sources and Origins ofAtmospheric Cloud Droplets) Åreskutan / Sweden (July 2003)1250 m asl., 63.4°N, 13.1°E CLACE-3 (Cloud and Aerosol Characterization Experiment) Jungfraujoch / Switzerland, (March 2004)3580 m asl., 46.55°N, 7.98°E

19. Cloud particle sampling Total aerosol Sampling Interstitial aerosol CVI Residuals Ice nuclei Ice crystals Cloud droplets Interstitial aerosol

20. Warm cloud (Sweden, July) Interstitial Particles • Residual particles slightly larger than interstitial particles (average: +60 nm). • Activation of nitrate down to 150 nm, other species down to 200 nm • Relative enrichment of nitrate and ammonium compared to organics and sulfate Cloud Residual Particles

21. Ice cloud (preliminary results) Interstitial Particles • Low concentration of non-refractory material in ice nuclei(CVI enrichment ca. 10) • Nitrate activated down to 250 nm, sulfate down to 300 nm • Relative enrichment of sulfate compared to nitrate CVI residuals

22. Supercooled cloud (preliminary results) Interstitial Particles • Almost all particles activated as CCN • interstitial aerosol almost depleted (from SPMS: activation from 70 nm on) • Nitrate and sulfate similar CVI residuals

23. Summary Answers to leading questions I • The AMS as one representative of "new directions"– what can be learned ? • Good time resolution, quantitative information,quasi-simultaneous composition and size distribution(however, non-refractory PM only) • Quantification needs laboratory work and additional information • Time resolution -> suited for aircraft-based measurements • Coupling of CVI and MS offers insight into cloudformation processes

24. Summary Answers to leading questions II • Mass spectrometric techniques may move into mainstrem monitoring in future (ca. 10 years)(Several issues still to be solved) • Missing: • Quantitative measurement of refractory components(Quantitative Single Particle Laser Ablation MS) • Quantitative non-refractory single particle information-> Aerodyne ToF-AMS • Identification of unknown mass peaks (organics)-> Ion trap - AMS • Extend size ranges! 5 nanometers (nucleation) to  50 micrometers (clouds)

25. Acknowledgments Frank Drewnick, Nele Hock, Silke Henseler, Silke Weimer, Saskia Walter, Joachim Curtius,Andreas Kürten, Matthias Ettner, Thomas Böttger, Stephan Borrmann Jos Lelieveld et al. (Crete campaign)Ulf Kirchner et al., (Ford Research Center)Bernd Kärcher et al. (PAZI aircraft campaign)Kevin Noone et al. (Areskutan)Ernest Weingartner et al. (Jungfraujoch)Doug Worsnop et al. (Aerodyne)