Speaker：Risto E. J. Hillamo

    Time：10:00 a.m.-11:30a.m., Sep 27nd
    Place：Room 301, the Old Geoscience Building
    Background：
 University of Helsinki, Finland:
  1981 B.Sc.
  1984 M.Sc. (physics)
  1989 Lic.Phil. (physics)
  1994 Ph.D. (physics)
  2002 Docent (physics)
    Introduction：In Helsinki there are a few emission source categories potentially contributing the ambient air quality: vehicular emissions, wood combustion, ship emissions and power and heat production. Power and heat is mainly produced in big centralized units with high stacks and emissions are not significantly found at ground level. Vehicular emissions over whole year and wood combustion winter time are the major sources of fine particles found at ground level. In this talk we will show examples of emission measurements in Helsinki, and how the fine particles appear in Helsinki ambient air. The measurement techniques used so far have been aerosol mass spectrometry (Aerodyne SP-AMS and ACSM), scanning mobility particle sizer, aerodynamic particle sizer, multi-angle absorption photometer, nephelometer and nano_micro-orifice uniform deposit impactor. Implications to air quality and climate change will be discussed.