Thermohygroscopic properties of biogenic particles from the sea-surface microlayer
Zusammenfassung der Projektergebnisse
Supported by the DFG the Leibniz-Institute for Tropospheric Research participated in the ASCOS icebreaker expedition in summer 2008. A Tandem Differential Mobility Spectrometer (TDMPS) and a Volatility Tandem Differential Mobility Analyser (VTDMA) were operated onboard. Within the central Arctic packice 567 hours of sub-micrometer particle size distributions were recorded over a wide dynamic range reachung from more than 1000 cm^-3 to below 1 cm^-3. In parallel the VTDMA measured the volatility of Aitken (≈40 nm diameter) and accumulation mode (170 nm) particles for the first time in the central Arctic. From the volatility of the particles information on their chemical composition was to be gathered. The particles exhibited rather little variability in their volatile characteristics, which was similar to that of ammonium sulfate. Only few ancillary parameters correlated with particle volatility, most prominently ozone, for which two alternative explanations are offered. For want of sample material from the ocean surface layer and because of limited staff resources the planned laboratory experiments aimed at simulating the generation of organic film drops could not be conducted. During recent decades and most likely continuing in the ongoing climate change dramatic changes have occurred in the Arctic concerning ice extent, thickness and related marine and continental boreal environment, all of which potentially affect the Arctic aerosol. With the ASCOS data for the fourth year a unique fourth aerosol data set was collected, now reaching from 1991 to 2008, which stimulated an ongoing comparative analysis of changes and similarities of the Arctic aerosol over 17 years in the light of regional climate changes.
Projektbezogene Publikationen (Auswahl)
- (2009) Surface-atmosphere exchange of aerosol particles in the high Arctic - Results from ASCOS. European Aerosol Conference 2009, September 6-11, 2009, Karlsruhe, Germany
Held, A., Orsini, D., Leck, C.
- Surface-atmosphere exchange of aerosol particles in the high Arctic - Results from ASCOS. European Aerosol Conference (EAC), Karlsruhe, Germany, 6-11 September (2009), pp. CD-ROM T160A101
Held, A., D. Orsini and C. Leck
- An Arctic CCN-limited cloud-aerosol regime. Atmos. Chem. Phys. 11, 165-173, 2010
Mauritsen, T., Sedlar, J., Tjernström, M., Leck, C., Martin, M., Shupe, M., Sjogren, S., Sierau, B., Persson, P. O. G., Brooks, I. M. and Swietlicki, E.
- Variability of the sub-micrometer aerosol in the summer Arctic, 2. ASCOS-Workshop, Stockholm, 5 March 2010
Orsini, D. and J. Heintzenberg
- (2011) Near-surface profiles of aerosol number concentration and temperature over the Arctic Ocean, Atmos. Meas. Tech., 4, 1603–1616
Held A., Orsini D.A., Vaattovaara P., Tjernström M., Leck C.
- (2011) The volatile fraction of Arctic aerosol particles derived from thermodenuder/mobility spectrometer measurements during ASCOS. European Aerosol Conference 2011, September 4-9, 2011, Manchester, UK
Held, A., Walz, J., Orsini, D., and Leck, C.
- Cloud condensation nuclei closure study on summer arctic aerosol. Atmos. Chem. Phys. Discuss. 11, 8801–8840, 2011
Martin, M., Chang, R. Y.-W., Sierau, B., Sjogren, S., Swietlicki, E., Abbatt, J. P. D., Leck, C. and Lohmann, U.
- Measurements of cloud condensation nuclei properties of remote and anthropogenic aerosols. Ph. D. Thesis. Department, ETH Zurich. 2011
Martin, M.
- On the potential contribution of open lead particle emissions to the central Arctic aerosol concentration. Atmos. Chem. Phys. 11, 3093-3105, 2011
Held, A., Brooks, I. M., Leck, C. and Tjernström, M.