The Possible Role of Heterogeneous Aerosol Processes in the Chemistry of CH4 and CO in the Troposphere

  1. David R. Schryer
  1. Cindy J. Luther and
  2. Leonard K. Peters

Published Online: 21 MAR 2013

DOI: 10.1029/GM026p0264

Heterogeneous Atmospheric Chemistry

Heterogeneous Atmospheric Chemistry

How to Cite

Luther, C. J. and Peters, L. K. (1982) The Possible Role of Heterogeneous Aerosol Processes in the Chemistry of CH4 and CO in the Troposphere, in Heterogeneous Atmospheric Chemistry (ed D. R. Schryer), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM026p0264

Author Information

  1. Department of Chemical Engineering, University of Kentucky, Lexington, Kentucky 40506

Publication History

  1. Published Online: 21 MAR 2013
  2. Published Print: 1 JAN 1982

ISBN Information

Print ISBN: 9780875900513

Online ISBN: 9781118663813

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Keywords:

  • Atmospheric chemistry—Addresses, essays, lectures

Summary

The tropospheric chemistry of CO and CH4 was analyzed to evaluate the role that heterogeneous interactions between trace gaseous species and aerosol particles covered by an aqueous layer could have on this oxidation sequence. In-cloud and below-cloud scavenging were not considered. The heterogeneous processes were represented by first-order rate expressions described by a heterogeneous loss constant based on classical mass transfer theory or gas-kinetic theory. Estimated global CO and CH4 emission rates and measured CH2O, H2O2, and HNO3 concentrations were used as a basis for comparing the results of two purely homogeneous gas-phase chemistry models with the same models which also included heterogeneous removal. On the basis of CH2O, H2O2, and HNO3 concentrations, the results indicated that the homogeneous models describe the CO–CH4 tropospheric chemistry more accurately, thereby suggesting that heterogeneous processes may not be significant in this sequence of chemical reactions. Estimates of the CO and CH4 emission rates did not provide a conclusive basis on which to compare the significance of the homogeneous and heterogeneous processes. Finally, the time period during which an aerosol particle is effective in removing a trace gaseous species from the troposphere was found to vary according to the tropospheric concentration and solubility of the particular gaseous species.