HR: 0830h
AN: A11E-0015    [PDF]
TI: Galactic Cosmic Rays and Ion Induced Aerosol Production
AU: * Kazil, J
EM: kazil@ucar.edu
AF: National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 United States
AU: Lovejoy, E R
EM: nlovejoy@al.noaa.gov
AF: National Oceanic and Atmospheric Administration, Atmospheric Chemical Kinetics Group, NOAA Aeronomy Laboratory, Mail code R/AL2, Boulder, CO 80305-3328 United States
AU: Desorgher, L
EM: desorgher@phim.unibe.ch
AF: University of Bern, Institute of Physics, Space Research and Planetary Sciences, Sidlerstr. 5, Bern, BE 3012 Switzerland
AB: The effect of ions on the production of sulfate aerosol in the Earth's atmosphere has been a topic of a number of modeling studies in the recent past. These studies were able to explain new particle formation in the middle and lower troposphere, observed in field campaigns under conditions where classical binary nucleation theory does not allow for a substantial particle production. However, recent observations of massive charged clusters in the upper troposphere indicate that ions may play an important role for aerosol formation in higher atmospheric regions as well. A major source of ions in the lower and middle atmosphere are galactic cosmic rays (GCR). The ion production due to GCR and the subsequent formation of sulfuric aerosol, together with its variations in altitude and solar cycle phase, were another topic of modeling studies. However, these studies relied mainly on theoretical approaches to ion-induced nucleation, and on sparse data of ion production in the atmosphere due to GCR. We present a study of aerosol formation based on laboratory thermochemistry data of negative sulfuric acid / water clusters and on modeled ion production rates due to GCR, covering different atmospheric regions. This approach allows for results which are subject to less quantitative uncertainties than previous work, and enables us to investigate and compare the aerosol production due to binary and ion-induced nucleation in various conditions.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0335 Ion chemistry of the atmosphere (2419, 2427)
DE: 2104 Cosmic rays
DE: 2419 Ion chemistry and composition (0335)
DE: 4801 Aerosols (0305)
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting