Importance of Heterogeneous Processes to Tropospheric Chemistry: Studies With a One-Dimensional Model
- David R. Schryer
Published Online: 21 MAR 2013
Copyright 1982 by the American Geophysical Union.
Heterogeneous Atmospheric Chemistry
How to Cite
Turco, R. P., Toon, O. B., Whitten, R. C., Keesee, R. G. and Hamill, P. (1982) Importance of Heterogeneous Processes to Tropospheric Chemistry: Studies With a One-Dimensional Model, in Heterogeneous Atmospheric Chemistry (ed D. R. Schryer), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM026p0231
- Published Online: 21 MAR 2013
- Published Print: 1 JAN 1982
Print ISBN: 9780875900513
Online ISBN: 9781118663813
- Atmospheric chemistry—Addresses, essays, lectures
The chemistry of the troposphere is affected by processes which involve the interactions between gases, aerosols and cloud droplets. Such “heterogeneous” processes are not usually considered in studies of the global tropospheric chemical cycles. (In the present context, the term “heterogeneous processes” refers to multiphase processes, processes involving particles and particle interactions, surface phenomena, and chemistry in solution, all as opposed to “homogeneous” gas-phase processes.) We have developed a one-dimensional model of tropospheric air composition which incorporates a number of heterogeneous physical and chemical processes. Gases, aerosols, and hydrometeors interact through the physical mechanisms of nucleation, condensation, evaporation, coagulation, coalescence, and deliquescence. Material is removed from the atmosphere by precipitation, sedimentation, and dry deposition. Chemical transformations occur both in the vapor and condensed (aerosol, raindrop) phases. The model also accounts for the sources and vertical diffusion of gases and particles, and for the changes in solar intensity caused by light-scattering from aerosols and clouds. We describe the structure of the model and compare preliminary computational results with other simulations and field data to demonstrate the accuracy of the model. It is shown that rainout and washout processes strongly influence the distributions of tropospheric gases and aerosols under certain conditions.